Source: MICHIGAN STATE UNIV submitted to NRP
INTEGRATED MANAGEMENT OF DISEASES OF SMALL FRUIT CROPS
Sponsoring Institution
National Institute of Food and Agriculture
Project Status
COMPLETE
Funding Source
HATCH
Reporting Frequency
Annual
Accession No.
0184696
Grant No.
(N/A)
Cumulative Award Amt.
(N/A)
Proposal No.
(N/A)
Multistate No.
(N/A)
Project Start Date
Jan 1, 2011
Project End Date
Dec 31, 2015
Grant Year
(N/A)
Program Code
[(N/A)]- (N/A)
Recipient Organization
MICHIGAN STATE UNIV
(N/A)
EAST LANSING,MI 48824
Performing Department
Plant, Soil and Microbial Science
Non Technical Summary
Small fruit crops are usually grown in perennial systems and are affected by a range of fungal diseases, which can significantly reduce fruit yield and quality as well as longevity of the planting. Due to high disease pressure and strict standards for fruit quality imposed by marketers and processors, small fruit growers in Michigan are highly dependent on synthetic chemicals for disease control. Virus diseases have become more important as well in recent years and emphasize the need to plant virus-free planting material. Even though growers are keen to incorporate integrated disease management methods including biological control agents, efficacious alternatives are often not available or cost-effective. Some fungicides are suspected carcinogens or may have endocrine effects. In addition, many of the new fungicides are prone to resistance development in target pathogens and also tend to be more expensive to apply per unit area than older fungicides. Therefore optimizing timing will become more crucial in order to reduce unnecessary or improperly timed sprays. These developments could leave small fruit growers with fewer or more costly disease control options and increased risks of crop losses in the future. In addition, genetic, cultural, and biological control methods need to be further investigated and evaluated to increase the number of non-chemical control options. There is an increasing interest in organic fruit production as well. The overall goal of this research project is to diversify disease management options for small fruit growers in Michigan. The results are expected to increase short-term profitability and long-term sustainability of the small fruit production and processing industries in Michigan by reducing production costs and environmental exposure associated with fungicide applications and increasing income due to improved yield and quality of fruit. Alternative disease control methods are expected to reduce environmental contamination by pesticides and improve food and worker safety, which should benefit growers and consumers alike. New techniques and information generated by this project will not only benefit growers in Michigan, but also in neighboring states. Trials will be done in the laboratory, greenhouse or field, including commercial fields. Outputs will include disease prediction models, extension bulletins and guides, training courses and workshop, electronic newsletters and webiste
Animal Health Component
(N/A)
Research Effort Categories
Basic
(N/A)
Applied
(N/A)
Developmental
(N/A)
Classification

Knowledge Area (KA)Subject of Investigation (SOI)Field of Science (FOS)Percent
2121120116040%
2121139116040%
2121122116010%
2121129116010%
Knowledge Area
212 - Pathogens and Nematodes Affecting Plants;

Subject Of Investigation
1120 - Blueberry; 1129 - Berries and cane fruits, general/other; 1122 - Strawberry; 1139 - Grapes, general/other;

Field Of Science
1160 - Pathology;
Goals / Objectives
The project aims to reduce the reliance on conventional chemicals and improve fruit yield and quality by diversifying disease control options for small fruit crops in an environmentally and economically sustainable manner. To achieve this, a better understanding of the biology of major fruit pathogens is needed to optimize use of existing disease control methods. Alternatives to current chemical control methods, such as the use of cultivar resistance, cultural and biological control methods, and disease scouting and forecasting, need to be explored. Integration of various disease control options needs further investigation as well. The specific objectives of the project are to: 1)Improve diagnosis of diseases and assessment of losses on small fruit crops 2)Elucidate the biology and population characteristics of small fruit pathogens 3)Study the effects of environmental factors and fungicides on small fruit pathogens 4)Evaluate the efficacy of integrated disease management methods Information generated by the project will be disseminated to small fruit growers, processors, extension agents, private consultants, and industry personnel by conventional and novel extension approaches, including research reports, extension bulletins, articles in trade publications, conference calls, presentations at grower meetings, short courses, field days, field demonstration sites, videos, and internet web sites. In addition, disease prediction models will be made available to growers and other users via the MSU Enviro-weather website. IPM pocket scouting guides have been developed for blueberries and grapes and new guides will be developed for strawberries and raspberries. A Blueberry Health Management, Grape IPM, and Organic Blueberry Production Guide will be developed as well. Promising disease control methods will be incorporated in state-wide integrated crop management recommendations, which will be disseminated as stated above. Information will be distributed to other fruit researchers via scientific journals, presentations at state, regional, national, and international research meetings, and personal communications. If promising methods have potential to be further developed by industry, appropriate contacts will be made with industry representatives, and where applicable, patents will be applied for.
Project Methods
The project will be conducted by addressing the following subobjectives: a) Diagnose diseases on commercial and homeowner small fruit samples, b) Virus diagnostic survey in grapes and blueberries, c) Disease-loss relationships for small fruit diseases, d) Characterize Colletotrichum acutatum isolates on small fruit crops in Michigan, e)Characterize host specialization and diversity of grape downy mildew in Michigan, f) Develop disease prediction models for anthracnose fruit rot and mummy berry in blueberry, g) Study environmental effects on pathogen inoculum production and survival, h)Validate disease prediction models for grapevine powdery and downy mildew, i)Pre- and post-infection activity and rainfastness of fungicides for small fruit pathogens, j)Study the effect of temperature on efficacy and systemicity of fungicides, k)Evaluate the efficacy of integrated disease management methods, l)Identify sources of resistance to diseases in small fruit crops, m)Evaluate cultural and scouting methods for control of small fruit diseases, n) Study the efficacy of reduced-risk and biological fungicides against small fruit diseases, o) Evaluate Precision agriculture applications in small fruit crops. Trials will be done in the laboratory, greenhouse or field, in a replicated trials with appropriate statistical analysis. In some cases, descriptive work will be done. Outputs will be evaluated by assessing changes in grower knowledge and practices using questionnaires, surveys, and case studies.

Progress 01/01/11 to 12/31/15

Outputs
Target Audience:The primary target audience for the project is small fruit growers and winery owners, nursery owners, extension personnel, field scouts and private consultants in Michigan and the Great Lakes region. In addition, the project reached small fruit growers and other stakeholders throughout the United states and the world, while undergraduate and graduate students, postdocs and visiting scientists also were educated in small fruit disease diagnosis and management as part of this project. Changes/Problems:There were no major changes in the approach, however, limitations on time and funding have delayed progress on some of the publications. What opportunities for training and professional development has the project provided?The project has provided four MS students, two PhD students, and eight undergraduate students with training and professional development opportunities. For the graduate students, this included research and teaching opportunities towards their degrees. For the undergraduate students, this included research experience. How have the results been disseminated to communities of interest?Information generated by the project was disseminated to small fruit growers, processors, extension agents, private consultants, and industry personnel via presentations at grower meetings, short courses and field days,extension bulletins, articles in extension and trade publications, training videos, and internet web sites (www.grapes.msu.edu; www.blueberries.msu.edu). In addition, disease prediction models were made available to growers and other users via the MSU Enviro-weather website. What do you plan to do during the next reporting period to accomplish the goals? Nothing Reported

Impacts
What was accomplished under these goals? In terms of the impact of the project, a better understanding of the identity and biology of small fruit pathogens is helping growers use the most appropriate fungicides and optimize fungicide timing for disease control. Growers are using more environmentally friendly fungicides and more growers are starting to grow fruit organically. Data on the effects of diseases on plant growth, fruit yield and quality help growers in assessing the costs and benefits of their control decisions. Studies on the environmental requirements for infection formed the basis for disease-forecasting models that use weather data to predict infection periods, resulting in improved disease control. Efficacy testing of reduced-risk fungicides, biological control products, natural products, and inorganic substances has led to a diversification of disease control options and reduced the dependency of blueberry growers on conventional fungicides, including older products that are suspected carcinogens. The efficacy data we obtained on new fungicides have helped growers feel confident about alternative options. New information on fungicide resistance in small fruit pathogens has helped growers choose more effective fungicides and implement fungicide resistance management strategies. Our work on dormant sprays has resulted in many small fruit growers integrating dormant sprays into their programs, lowering disease pressure during the growing season. New information on fungicide rainfastness and fungicide application efficiency is being applied immediately to optimize fungicide timing and of fungicide spray technology. Identification of sources and mechanism of disease resistance and improved screening techniques are facilitating blueberry breeding efforts to develop resistant cultivars. New knowledge on cultivar resistance included in fact sheets and the Michigan Fruit Management Guide is also helping growers adjust their management strategies. Evaluation of biocontrol agents and cultural practices on disease severity has helped growers choose management practices that are more ecologically friendly. Our research on virus diseases in grapes and blueberries has increased awareness of virus problems in small fruit crops, resulting in changes in management practices, such as increased use of certified virus-tested plant material. Our research also feeds information into the Berry Clean Plant Network which has been established to produce virus-free foundation stock to nurseries. Results from this project are expected to have environmental, worker, and consumer benefits by reducing chemical use in fruit production. The project helps to maintain short-term and long-term viability of small fruit production in the United States. Accomplishments by objective: 1) Improve diagnosis of diseases and assessment of losses on small fruit crops. We have identified a number of new fungal diseases in Michigan, leaf rust, Pythium root rot, and Calonectria stem rot in blueberries, and a new rust disease and Phytophthora root rot in saskatoonberries. We conducted virus surveys in grapes and blueberries, identifying various viruses not heretofore reported in Michigan, includuing grapevine leafroll- and rugose-wood-associated viruses in grapes, and bronze leaf curl in blueberries. These surveys have also helped to quantify the relative incidence and importance of viruses in small fruit crops. Assessment of losses due to GLRaV-3 and tobacco ringspot virus provided information on the potential consequences of these infections. Various Phomopsis species in addition to P. vaccinii were found in a survey on the causes of cane dieback in Michigan. Furthermore, a study on the effect on Phomopsis twig blight and canker suggests that there may be compensation by the plant but that cultivars respond differently to infection and may need to be managed differently. Studies on yield losses due to foliar powdery and downy mildew in grapes indicated that only severe disease resulted in measurable losses in fruit quality, particularly in the case of downy mildew. 2) Elucidate the biology and population characteristics of small fruit pathogens We studied fungicide resistance in populations of Erysiphe necator (grape powdery mildew) and Botrytis cinerea (gray mold) in strawberry and grape; and Colletotrichum acutatum (anthracnose fruit rot) and Monilinia vaccinii corymbosi (mummy berry) in blueberry. There was clear evidence of strobilurin resistance in grape powdery mildew, but more so in research sites than in commercial vineyards. There was also an indication of sterol inhibitor resistance. In Botrytis cinerea, almost all isolates had resistance to thiophanate methyl and pyraclostrobin, with limited resistance to other chemical classes. The incidence of resistance varied widely between farms, with more resistance in strawberries than grapes. Fungicide resistance was not detected in M. vaccinii-corymbosi but C. acutatum is showing evidence of strobilurin insensitivity.Genetic diversity was assessed using ITS and EF genes in Phomopsis vaccinii from blueberries and a similar study is ongoing in M. vaccinii-corymbosi and C. acutatum. We studied the production of chasmothecia (overwintering structures) in powdery mildew colonies on grape leaves in the fall and found that peak production of chasmothecia occurs in mid- to late September, which can be interrupted with eradicant fungicide sprays. 3) Study the effects of environmental factors and fungicides on small fruit pathogens The effect of environmental variables on apothecial development, ascospore release and ascosporic infection by M. vaccinii-corymbosi (mummy berry) in blueberry was studied in order to develop and validate an infection model for enviro-weather. In addition, we studied the effects of environmental variables on fruit infection by C. acutatum and developed a disease prediction model which is now available on Enviroweather, an automated weather network of Michigan State University. In addition, we studied the effects of weather variables on powdery mildew ascospore release, resulting in the conclusion that ascospores are present in the air throughout the spring, after rain events but for at least a week afterwards and that the limiting factor is probably suitable temperatures for the establishment of colonies. We evaluated new, organically approved and other "softer" fungicides in over 60 field trials over the course of the project, which has led to new and improved recommendations for the use of these fungicides in Michigan and other regions. Many of these fungicides are now registered for use and available to small fruit growers, including for organic production. Furthermore, we have studied rainfastness of fungicides on grapes and blueberries and have improved our recommendations with respect to the need for re-application after rainfall. 4) Evaluate the efficacy of integrated disease management methods We have evaluated pruning and sanitation as a method for control of Phomopsis twig blight in blueberries and black rot and Phomopsis in grapes. Leaf pulling around grape clusters was effective for control of sour rot and Botrytis bunch rot in grapes.We have been studying compost teas for disease suppression and have identified specific composts which provide suppression of powdery mildew, black rot and other grape diseases when made into compost teas. We are currently studying the microbial communities in compost teas that contribute to disease suppressiveness as well as the effect on soil biology. We have identified several mechanisms of anthracnose fruit rot resistance in 'Elliott' blueberries, such as accumulation of antifungal compounds, an oxidative burst, high sugar levels, and acidity. We have also studied the inheritance of resistance which appears to be polygenic.

Publications

  • Type: Books Status: Published Year Published: 2015 Citation: Schilder, A., Isaacs, R., Hanson, E., Cline, B. 2015. A Pocket Guide to IPM Scouting in Highbush Blueberries, 3rd edition. Michigan State University Extension Bulletin E-2928
  • Type: Other Status: Published Year Published: 2015 Citation: Elsner, E., Schilder, A., and Isaacs, R. 2015. Saskatoonberry Pesticide Recommendations for Michigan. 10 pp
  • Type: Journal Articles Status: Published Year Published: 2015 Citation: Thekke-Veetil, T., Polashock, J., Marn, M. V., Plesko, I.M., Schilder, A. C., Keller, K. E., Martin, R. R., and Tzanetakis, I. E. 2015. Population structure of blueberry mosaic associated virus: evidence of genetic exchange in geographically distinct isolates. Virus Research 201:7984
  • Type: Journal Articles Status: Published Year Published: 2014 Citation: Claudius-Cole, A. O., Ekpo, E. J. A., and Schilder, A. M. C. 2014. Evaluation of detection methods for cowpea bacterial blight caused by Xanthomonas axonopodis pv vignicola in Nigeria. Tropical Agricultural Research and Extension 17: 77-85
  • Type: Conference Papers and Presentations Status: Published Year Published: 2015 Citation: Arocha-Rosete, Y., Schilder, A., Lambert, L., and Scott, J. 2015. Identification and molecular characterization of the blueberry stunt phytoplasma in Canada. Phytopathogenic Mollicutes 5(1-Supplement) S17-18
  • Type: Other Status: Published Year Published: 2015 Citation: Schilder, A. M. C., Gillett, J. M., and Sysak, R. W. 2015. Evaluating fungicides and biocontrol products for control of mummy berry in blueberries, 2014. Plant Disease Management Reports 9:SMF038.
  • Type: Other Status: Published Year Published: 2015 Citation: Schilder, A. M. C., Gillett, J. M., and Sysak, R. W. 2015. Evaluating fungicides for control of anthracnose fruit rot in blueberries, 2014. Plant Disease Management Reports 9:SMF037.
  • Type: Other Status: Published Year Published: 2015 Citation: 3. Schilder, A. M. C., Gillett, J. M., and Sysak, R. W. 2015. Evaluation of fungicides for control of post-harvest fruit rots and leaf blight in strawberry, 2014. Plant Disease Management Reports 9:SMF036
  • Type: Other Status: Published Year Published: 2015 Citation: Schilder, A. M. C., Gillett, J. M., and Sysak, R. W. 2015. Evaluation of organic fungicides for control of strawberry foliar and fruit diseases, 2014. Plant Disease Management Reports 9:SMF035.
  • Type: Other Status: Published Year Published: 2015 Citation: Schilder, A. M. C., Gillett, J. M., and Sysak, R. W. 2015. Evaluation of fungicides for control of powdery mildew in tunnel-grown strawberries, 2014. Plant Disease Management Reports 9:SMF034.
  • Type: Other Status: Published Year Published: 2015 Citation: Schilder, A. M. C., Gillett, J. M., and Sysak, R. W. 2015. Evaluation of fungicides for control of powdery mildew in tunnel-grown raspberries, 2014. Plant Disease Management Reports 9:SMF033
  • Type: Other Status: Published Year Published: 2015 Citation: Schilder, A. M. C., Gillett, J. M., and Sysak, R. W. 2015. Evaluation of fungicides for control of foliar and fruit rot diseases in juice grapes, 2014. Plant Disease Management Reports 9:SMF032.
  • Type: Other Status: Published Year Published: 2015 Citation: Schilder, A. M. C., Gillett, J. M., and Sysak, R. W. 2015. Evaluation of fungicides for control of Botrytis bunch rot in Aurore grapes, 2014. Plant Disease Management Reports 9:SMF031.
  • Type: Other Status: Published Year Published: 2015 Citation: Schilder, A. M. C., Gillett, J. M., and Sysak, R. W. 2015. Evaluation of dormant sprays and fungicide programs for control of black rot and Phomopsis in juice grapes, 2014. Plant Disease Management Reports 9:SMF030.
  • Type: Other Status: Published Year Published: 2015 Citation: Schilder, A. M. C., Gillett, J. M., and Sysak, R. W. 2015. Evaluating fungicides and compost teas for control of mummy berry and post-harvest fruit rots in blueberries, 2013. Plant Disease Management Reports 9:SMF029
  • Type: Other Status: Published Year Published: 2015 Citation: Schilder, A. 2015. Protect hail-damaged grape clusters from Botrytis infection. MSU Extension News for Agriculture (http://news.msue.msu.edu/news/category/fruit). Posted on Aug 4, 2015.
  • Type: Other Status: Published Year Published: 2015 Citation: Schilder, A. 2015. Weather ideal for start of downy mildew in grapes. MSU Extension News for Agriculture (http://news.msue.msu.edu/news/category/fruit). Posted on June 23, 2015.
  • Type: Other Status: Published Year Published: 2015 Citation: Schilder, A. 2015. Young cane dieback becoming obvious in Michigan blueberry fields. MSU Extension News for Agriculture (http://news.msue.msu.edu/news/category/fruit). Posted on June 12, 2015.
  • Type: Other Status: Published Year Published: 2015 Citation: Schilder, A. 2015. Protect strawberries from foliar diseases after renovation. MSU Extension News for Agriculture (http://news.msue.msu.edu/news/category/fruit). Posted on July 15, 2015.
  • Type: Other Status: Published Year Published: 2015 Citation: Schilder, A. 2015. Assistance in raspberry virus diagnosis offered. MSU Extension News for Agriculture (http://news.msue.msu.edu/news/category/fruit). Posted on June 2, 2015.
  • Type: Other Status: Published Year Published: 2015 Citation: Schilder, A. 2015. Mummy berry management in blueberries during bloom. MSU Extension News for Agriculture (http://news.msue.msu.edu/news/category/fruit). Posted on May 26, 2015.
  • Type: Other Status: Published Year Published: 2015 Citation: Schilder, A. 2015. Merivon, a new fungicide option for disease control in strawberries. MSU Extension News for Agriculture (http://news.msue.msu.edu/news/category/fruit). Posted on May 21, 2015.
  • Type: Other Status: Published Year Published: 2015 Citation: Schilder, A. 2015. Disease management considerations for winter-injured blueberries. MSU Extension News for Agriculture (http://news.msue.msu.edu/news/category/fruit). Posted on June 16, 2015.
  • Type: Other Status: Published Year Published: 2015 Citation: Schilder, A. 2015. Excessive rain promotes Phytophthora diseases in raspberries and strawberries. MSU Extension News for Agriculture (http://news.msue.msu.edu/news/category/fruit). Posted on June 23, 2015.
  • Type: Other Status: Published Year Published: 2015 Citation: Schilder, A. M. C., Gillett, J. M., and Sysak, R. W. 2015. Evaluation of fungicides for control of post-harvest fruit rot diseases in matted-row strawberries, 2013. Plant Disease Management Reports 9:SMF028.
  • Type: Other Status: Published Year Published: 2015 Citation: Schilder, A. 2015. Protect grape clusters from all major grape diseases during early fruit development. MSU Extension News for Agriculture (http://news.msue.msu.edu/news/category/fruit). Posted on June 2, 2015.
  • Type: Other Status: Published Year Published: 2015 Citation: Schilder, A. 2015. Use anthracnose fruit rot prediction model to assess risk of infection. MSU Extension News for Agriculture (http://news.msue.msu.edu/news/category/fruit). Posted on June 30, 2015.
  • Type: Other Status: Published Year Published: 2015 Citation: Schilder, A. 2015. The challenges of disease control during rainy spells. MSU Extension News for Agriculture (http://news.msue.msu.edu/news/category/fruit). Posted on May 12, 2015.
  • Type: Other Status: Published Year Published: 2015 Citation: Baughman, B., and Schilder, A. 2015. Protect new grape shoots from early-season fungal diseases from all major grape diseases during early fruit development. MSU Extension News for Agriculture (http://news.msue.msu.edu/news/category/fruit). Posted on May 12, 2015.
  • Type: Other Status: Published Year Published: 2015 Citation: Schilder, A. 2015. Protect against blossom blights in blueberries. MSU Extension News for Agriculture (http://news.msue.msu.edu/news/category/fruit). Posted on May 6, 2015.
  • Type: Other Status: Published Year Published: 2015 Citation: Mason, K., Baughman, B., Schilder, A., and Isaacs, R. 2015. Southwest Michigan grape scouting report for September 7, 2015. MSU Extension News for Agriculture (http://news.msue.msu.edu/news/category/ fruit). Posted on Sep 9, 2015.
  • Type: Other Status: Published Year Published: 2015 Citation: Mason, K., Baughman, B., Schilder, A., and Isaacs, R. 2015. Southwest Michigan grape scouting report for August 25, 2015. MSU Extension News for Agriculture (http://news.msue.msu.edu/news/category/ fruit). Posted on Aug 25, 2015.
  • Type: Other Status: Published Year Published: 2015 Citation: Mason, K., Baughman, B., Schilder, A., and Isaacs, R. 2015. Southwest Michigan grape scouting report for August 11, 2015. MSU Extension News for Agriculture (http://news.msue.msu.edu/news/category/ fruit). Posted on Aug 11, 2015.
  • Type: Other Status: Published Year Published: 2015 Citation: Baughman, B., Mason, K., Schilder, A., and Isaacs, R. 2015. Vineyard IPM scouting report for June 15, 2015. MSU Extension News for Agriculture (http://news.msue.msu.edu/news/category/ fruit). Posted on Jun 16, 2015.
  • Type: Other Status: Published Year Published: 2015 Citation: Mason, K., Baughman, B., Schilder, A., and Isaacs, R. 2015. Vineyard IPM scouting report for May 24-June 1, 2015. MSU Extension News for Agriculture (http://news.msue.msu.edu/news/category/ fruit). Posted on Jun 2, 2015.
  • Type: Other Status: Published Year Published: 2015 Citation: Mason, K., Baughman, B., Schilder, A., and Isaacs, R. 2015. Southwest Michigan grape scouting report for July 28, 2015. MSU Extension News for Agriculture (http://news.msue.msu.edu/news/category/ fruit). Posted on Jul 28, 2015.
  • Type: Other Status: Published Year Published: 2015 Citation: Baughman, B., Mason, K., Schilder, A., and Isaacs, R. 2015. Southwest Michigan grape scouting report for July14, 2015. MSU Extension News for Agriculture (http://news.msue.msu.edu/news/category/ fruit). Posted on Jul 14, 2015.
  • Type: Other Status: Published Year Published: 2015 Citation: Baughman, B., Mason, K., Schilder, A., and Isaacs, R. 2015. Vineyard IPM scouting report for June 30, 2015. MSU Extension News for Agriculture (http://news.msue.msu.edu/news/category/ fruit). Posted on Jun 30, 2015.


Progress 10/01/13 to 09/30/14

Outputs
Target Audience: The primary target audience for the project is small fruit growers, nursery owners, extension personnel and private consultants in Michigan and the Great Lakes region. in addition, the project reaches small fruit growers and other stakeholders throughout the United states and the world. Furthermore, undergraduate and graduate students are being educated in small fruit disease diagnosis and management as part of this project. Changes/Problems: No major changes have occurred. We did experience problems in having our fungicide samples analyzed for pesticide residues due to personnel problems and equipment breakdown in the MSU Pesticide Analysis Laboratory. What opportunities for training and professional development has the project provided? The project has provided a Master's student, a PhD studentand two undergraduate students, with training and professional development opportunities. How have the results been disseminated to communities of interest? The results have been communicated to communities of interest by means of extension bulletins, extension articles, presentations at grower meetings and webinars, radiointerviews, websites, and through field visits and diagnostic support to growers and consultants. in addition, presentations have been made at scientific conferences andpapers published inscientific journals. What do you plan to do during the next reporting period to accomplish the goals? I plan to continue the research we are currently involved in.

Impacts
What was accomplished under these goals? We continued to studycane and twig blight in Michigan blueberry fields. Most fungi isolated from cankers belonged to the fungal genus Phomopsis, especially P. vaccinii but also P. eres. Twig blight was caused by a number of pathogens, particularly P. vaccinii, Colletotrichum acutatum and Pseudomonas syringae. We also studied yield loss to the twig blight stage and the role of phenological stage, cane age, frost and herbicide injury. Blueberries were most susceptible to infection at the pink bud and bloom stages; frost did not increase susceptibility but herbicide use (paraquat and glyphosate) did. In addition, current-year canes were the most susceptible to infection. We continued to study the effects of leaf wetness and temperature on mummy berry infection and to evaluate the anthracnose disease prediction model in a field trial. Field studies of biofungicide efficacy showed moderate to good control of mummy berry. Trials with biocontrol agents, especially Trichoderma spp., applied in the fall showed a reduction in grape black rot and Phomopsis inoculum in the spring. We continued the virus survey in grapes in collaboration with Dr. Naidu Rayapati in Prosser, WA. The spatial distribution of GLRaV-3 and tomato ringspot virus was studied in a vineyard where over 90% of the vines were found to be infected. In addition, yield loss was studied and amounted to more than 80% in vines infected by both viruses. However, mildly and moderately GLRaV-vines did not show much yield loss. Fungicide efficacy trials were conducted for management of powdery mildew, downy mildew, black rot, Phomopsis and bunch rots in grapes; most fungicides were quite efficacious. A number of new fungicides were evaluated and rankings were incorporated in the Michigan Fruit Management Guide. Powdery mildew samples were collected for a study on inhibitor fungicide resistance, which is currently ongoing. In addition, we collected isolates of Botrytis cinerea from field of strawberries and grapes, and C. acutatum from fields of strawberries and blueberries to evaluate fungicide resistance in collaboration with Dr. Guido Schnabel at Clemson University. Fungicide resistance varied widely among farms, from none to resistance against 7 out of 9 fungicides tested. In addition, we studied temperature effects on uptake of fungicides in grapes and blueberries; some fungicides, like strobilurins, were not taken up well at 4C compared to 18C and 32C. Oil sprays were evaluated again for powdery mildew eradication. The fungicide Tritek appears to be particularly effective due to its micro-emulsion properties. We have also continued to evaluate disease suppressiveness of compost teas, both in the greenhouse and in vineyards. Some compost teas reduced powdery mildew in grapes and cucumbers and other reduced Pythium damping off in beans. Effects on soil and phyllosphere biology and nutrient levels in the plant are being investigated As a result of our research, growers are using more environmentally friendly fungicides and disease control approaches. As prices of certain fungicides increased, our efficacy data helped growers select choose other cost-effective alternatives. Disease forecasting models are anticipated to result in a reduction in fungicide applications and improved disease control. Results from this project are expected to have environmental, worker, and consumer benefits by reducing chemical use in fruit production. The project will also help maintain economic viability of small fruit production in the United States.

Publications

  • Type: Other Status: Published Year Published: 2014 Citation: Schilder, A. 2014. Special local need label for the fungicide Switch for aerial application in blueberries. MSU Extension News for Agriculture (http://news.msue.msu.edu/news/category/fruit). Posted on Jul 9, 2014.
  • Type: Other Status: Published Year Published: 2014 Citation: Schilder, A. 2014. Botrytis gray mold control in strawberries and raspberries. MSU Extension News for Agriculture (http://news.msue.msu.edu/news/category/fruit). Posted on Jul 1, 2014.
  • Type: Other Status: Published Year Published: 2014 Citation: Schilder, A. 2014. Humid weather increases Botrytis gray mold pressure in fall raspberries. MSU Extension News for Agriculture (http://news.msue.msu.edu/news/category/fruit). Posted on Sep. 3, 2014.
  • Type: Other Status: Published Year Published: 2014 Citation: Schilder, A. 2014. How to get the most out of your fungicide sprays. MSU Extension News for Agriculture (http://news.msue.msu.edu/news/category/fruit). Posted on Jul 8, 2014.
  • Type: Conference Papers and Presentations Status: Published Year Published: 2014 Citation: Thekke-veetil, T. Polashock, J. Plesko, i. M., Keller, K. E., Martin, R. R., Schilder, A., Ho, T., Tzanetakis, I. E. 2014. Molecular characterization and genetic variation of an ophiovirus associated with blueberry mosaic. APS Annual Meeting, Minneapolis, MN, Aug. 9-13, 2014 (poster).
  • Type: Journal Articles Status: Published Year Published: 2014 Citation: Rouxel, M., Mestre, P., Baudoin, A., Carisse, O., Deli�re, L., Ellis, M. A., Gadoury, D., Lu, J., Nita, M., Richard-Cervera, S., Schilder, A., Wise, A., Delmotte, F. 2013. Geographic distribution of species of Plasmopara viticola causing downy mildew on wild and cultivated grapes in Eastern North America. Phytopathology 104:692-701. doi: 10.1094/PHYTO-08-13-0225-R.
  • Type: Other Status: Awaiting Publication Year Published: 2014 Citation: Wise, J. C., Gut, L. J., Isaacs, R., Schilder, A. M. C., Sundin, G. W., Zandstra, B., Hanson, E., and Shane, B. 2014. Michigan Fruit Management Guide 2015. Extension Bulletin E-154. Michigan State University, East Lansing, MI (Dec. 2014)
  • Type: Other Status: Published Year Published: 2014 Citation: Elsner, E., Schilder, A., and Isaacs, R. 2014. Saskatoonberry Pesticide Recommendations. 11 pp. MSU Extension .
  • Type: Other Status: Published Year Published: 2014 Citation: Schilder, A. 2014. Controlling black rot and Phomopsis in grape clusters. MSU Extension News for Agriculture (http://news.msue.msu.edu/news/category/fruit). Posted on Jul 1, 2014.
  • Type: Journal Articles Status: Published Year Published: 2014 Citation: Endeshaw, S. T., Sabbatini, P., Gianfranco Romanazzi, G., Schilder, A. C., and Neri, D. 2014. Effects of grapevine leafroll associated virus 3 infection on growth, leaf gas exchange, yield and basic fruit chemistry of Vitis vinifera L. cv. Cabernet Franc. Scientia Horticulturae 170: 228236.
  • Type: Other Status: Published Year Published: 2014 Citation: Schilder, A. 2014. Weather is ideal for downy mildew on grapes at this time. MSU Extension News for Agriculture (http://news.msue.msu.edu/news/category/fruit). Posted on Jul 1, 2014.
  • Type: Other Status: Published Year Published: 2014 Citation: Schilder, A. 2014. What to do when you start seeing disease in the vineyard: Post-infection treatments. MSU Extension News for Agriculture (http://news.msue.msu.edu/news/category/fruit). Posted on Jul 29, 2014.
  • Type: Other Status: Published Year Published: 2014 Citation: Schilder, A. 2014. Dont let bunch rots ruin your grapes. MSU Extension News for Agriculture (http://news.msue.msu.edu/news/category/fruit). Posted on Aug 26, 2014.
  • Type: Other Status: Published Year Published: 2014 Citation: Schilder, A. 2014. Botrytis fungicide-resistance survey for grape growers. MSU Extension News for Agriculture (http://news.msue.msu.edu/news/category/fruit). Posted on Aug 19, 2014.
  • Type: Other Status: Published Year Published: 2014 Citation: Schilder, A. 2014. Downy mildew and powdery mildew gaining ground in grapes. MSU Extension News for Agriculture (http://news.msue.msu.edu/news/category/fruit). Posted on Aug 26, 2014.
  • Type: Other Status: Published Year Published: 2014 Citation: Mason, K., Schilder, A., and Isaacs, R. 2014. Vineyard IPM scouting report for Jul 15, 2014. MSU Extension News for Agriculture (http://news.msue.msu.edu/news/category/fruit). Posted on Jul 15, 2014.
  • Type: Other Status: Published Year Published: 2014 Citation: Mason, K., Schilder, A., and Isaacs, R. 2014. Vineyard IPM scouting report for Aug 25, 2014. MSU Extension News for Agriculture (http://news.msue.msu.edu/news/category/fruit). Posted on Aug 26, 2014.
  • Type: Other Status: Published Year Published: 2014 Citation: Mason, K., Schilder, A., and Isaacs, R. 2014. Vineyard IPM scouting report for Aug 11, 2014. MSU Extension News for Agriculture (http://news.msue.msu.edu/news/category/fruit). Posted on Aug 12, 2014.
  • Type: Other Status: Published Year Published: 2014 Citation: Mason, K., Schilder, A., and Isaacs, R. 2014. Vineyard IPM scouting report for 28 July, 2014. MSU Extension News for Agriculture (http://news.msue.msu.edu/news/category/fruit). Posted on 29 Jul, 2014.
  • Type: Other Status: Published Year Published: 2014 Citation: Mason, K., Schilder, A., and Isaacs, R. 2014. Vineyard IPM scouting report for June 30, 2014. MSU Extension News for Agriculture (http://news.msue.msu.edu/news/category/fruit). Posted on July 1, 2014.
  • Type: Other Status: Published Year Published: 2014 Citation: Mason, K., Schilder, A., and Isaacs, R. 2014. Vineyard IPM scouting report for June 2, 2014. MSU Extension News for Agriculture (http://news.msue.msu.edu/news/category/fruit). Posted on June 3, 2014.
  • Type: Other Status: Published Year Published: 2014 Citation: Mason, K., Schilder, A., and Isaacs, R. 2014. Vineyard IPM scouting report for May 12-19, 2014. MSU Extension News for Agriculture (http://news.msue.msu.edu/news/category/fruit). Posted on May 20, 2014.
  • Type: Other Status: Published Year Published: 2014 Citation: Schilder, A. 2014. Be on the lookout for leaf rust in Michigan blueberry fields. MSU Extension News for Agriculture (http://news.msue.msu.edu/news/category/fruit). Posted on Aug 19, 2014.


Progress 01/01/13 to 09/30/13

Outputs
Target Audience: The primary target audience for the project is small fruit growers, nursery owners, extension personnel and private consultants in Michigan and the Great Lakes region. In addition, undergraduate and graduate students are being educated in small fruit disease diagnosis and management as part of this project. Changes/Problems: No major changes in approach were made. What opportunities for training and professional development has the project provided? The project helped train an MS student and fiour undergraduate students; in addition a part-time technician and two full-time technician enhanced their experience in plant pathology research and teaching. Results were also used to teach graduate students in guest lectures in the "Plant Diseases in the Field" course, "Organic Pest Management" Course. How have the results been disseminated to communities of interest? Results were shared with stakeholders through presentations at extension meetings, extension articles and bulletins, videoclips, and a radio interview. In addition, results were shared with the scientific community via presentations at scientific conferences and via publications in scientific journals. What do you plan to do during the next reporting period to accomplish the goals? We will continue to work on the projects listed above.

Impacts
What was accomplished under these goals? We studied the cause of cane and twig blight in a survey in Michigan blueberry fields. Most fungi isolated from cankers belonged to the fungal genus Phomopsis, and within that, P. vaccinii predominated. Twig blight was caused by a number of pathogens, particularly P. vaccinii, Colletotrichum acutatum and Pseudomonas spp. We also studied yield loss to the twig blight stage and the role of phenological stage, cane age, frost and herbicide injury. Flowering twigs and young canes were the most susceptible stage; frost did not increase flower susceptibility. We also continued to study blueberry bronze leaf curl, a new disease of blueberry in collaboration with Dr. Robert Martin at the USDA-Corvallis; the pathogen appears to be a closterovirus similar to blueberry virus A reported from Japan. In addition, we established a field trial to study potential spread of blueberry mosaic virus in collaboration with Dr. Yannis Tzanetakis at the U. Arkansas. We continued to study blueberry leaf rust, caused by Thekopsora minima, and showed that several fungicides are quite effective, particularly Pristine, Indar and Quash. A biocontrol product, Serenade, was moderate in its level of control, whereas JMS Stylet Oil and Oxidate did not work very well. We continued to study the effects of leaf wetness and temperature on mummy berry infection and to evaluate the anthracnose disease prediction model in a field trial. Field studies of regular and biofungicide efficacy showed moderate to good control of mummy berry. We continued the virus survey in grapes and samples are currently being analyzed by Dr. Naidu Rayapati in Prosser, WA. The spatial distribution of GLRaV-3 and tomato ringspot virus was studied in a vineyard where over 90% of the vines were found to be infected. In addition, yield loss was studied and amounted to more than 80% in vines infected by both viruses. However, mildly and moderately GLRaV-vines did not show much yield loss. Fungicide efficacy trials were conducted for management of powdery mildew, downy mildew, bunch rots and fruit rots in grapes; most fungicides were quite efficacious. A number of new fungicides were evaluated and rankings were incorporated in the Michigan Fruit Management Guide. Powdery mildew samples were collected for a study on inhibitor fungicide resistance, which is currently ongoing. In addition, we collected isolates of Botrytis cinerea from field of strawberries and grapes, and C. acutatum from fields of strawberries and blueberries to evaluate fungicide resistance in collaboration with Dr. Guido Schnabel at Clemson University. In addition, we conducted trials to evaluate rainfastness and temperature effects of uptake of fungicides in grapes and blueberries; data are currently being analyzed. We also evaluated a grower-designed sprayer for application of dormant sprays and found it to be more effective than an airblast sprayer in terms of coverage and control. Oil sprays were evaluated for powdery mildew eradication. The fungicide Tritek appears to be particularly effective due to its micro-emulsion properties. Tunnel-grown raspberries and cherries were assessed for disease development. Powdery mildew was seen in both cherries and raspberries; leaf rust was found at the end of the growing season in raspberries. We have also continued to evaluate disease suppressiveness of compost teas. As a result of our research, growers are using more environmentally friendly fungicides and disease control approaches. As prices of certain fungicides increased, our efficacy data helped growers select choose other cost-effective alternatives. Disease forecasting models are anticipated to result in a reduction in fungicide applications and improved disease control. Results from this project are expected to have environmental, worker, and consumer benefits by reducing chemical use in fruit production. The project will also help maintain economic viability of small fruit production in the United States.

Publications

  • Type: Journal Articles Status: Published Year Published: 2013 Citation: Miles, T. D., Nair, M. G., Vandervoort, C., and Schilder, A. M. C. 2013. Characterization and biological activity of flavonoids from ripe fruit of an anthracnose-resistant blueberry cultivar. Physiological and Molecular Plant Pathology 83:8-16. Lansing, MI.
  • Type: Books Status: Published Year Published: 2013 Citation: 1. Wise, J. C., Gut, L. J., Isaacs, R., Schilder, A. M. C., Sundin, G. W., Zandstra, B., Hanson, E., and Shane, B. 2013. Michigan Fruit Management Guide 2014. Extension Bulletin E-154. Michigan State University, East Lansing, MI.
  • Type: Books Status: Awaiting Publication Year Published: 2013 Citation: Bouma, E., Schilder, A., Andresen, J., Wise, J., and Zandstra, B. 2013. Weather and Crop Protection, US edition. Roodbont Publishers, Zutphen, The Netherlands.
  • Type: Journal Articles Status: Awaiting Publication Year Published: 2013 Citation: Miles, T. D., and Schilder, A. M. C. 2013. Host defenses associated of with fruit infection by Colletotrichum species with an emphasis on anthracnose of blueberries. Plant Health Progress
  • Type: Journal Articles Status: Awaiting Publication Year Published: 2013 Citation: Rouxel, M., Mestre, P., Baudoin, A., Carisse, O., Deli�re, L., Ellis, M. A., Gadoury, D., Lu, J., Nita, M., Richard-Cervera, S., Schilder, A., Wise, A., Delmotte, F. 2013. Geographic distribution of species of Plasmopara viticola causing downy mildew on wild and cultivated grapes in Eastern North America. Phytopathology
  • Type: Journal Articles Status: Submitted Year Published: 2013 Citation: Arango, J., Rubino, M. I., Auras, R., Gillett, J., and Schilder, A. C., and Grzesiak, A. L. 2013. Evaluation of chlorine dioxide as an antimicrobial against Botrytis cinerea in California strawberries. Journal of Food Protection
  • Type: Journal Articles Status: Submitted Year Published: 2013 Citation: Endeshaw, S. T., Sabbatini, P., Gianfranco Romanazzi, G., Schilder, A. C., and Neri, D. Effects of grapevine leafroll (GRLaV-3) infection on growth, leaf gas exchange, yield and basic fruit chemistry of cv. Cabernet Franc (Vitis vinifera L.) grapevines. Scientia Horticulturae
  • Type: Other Status: Awaiting Publication Year Published: 2013 Citation: Schilder, A. M. C. 2013. Phomopsis twig blight and canker. Blueberry Facts, Michigan State University Extension Fact Sheet E-3039.
  • Type: Journal Articles Status: Published Year Published: 2013 Citation: Miles, T. D., Gillett, J. M., Jarosz, A. M., and Schilder, A. M. C. 2013. The effect of environmental factors on infection of blueberry fruit by Colletotrichum acutatum. Plant Pathology (online) DOI: 10.1111/ppa.12061.
  • Type: Other Status: Published Year Published: 2013 Citation: Schilder, A. M. C., Gillett, J. M., and Sysak, R. W. 2013. Evaluating fungicides for control of post-harvest fruit rots in blueberries, 2012. Plant Disease Management Reports 7:SMF01. Schilder, A. M. C., Gillett, J. M., and Sysak, R. W. 2013. Evaluation of fungicides for control of foliar and fruit diseases in red raspberries, 2012. Plant Disease Management Reports 7:SMF008. Schilder, A. M. C., Gillett, J. M., and Sysak, R. W. 2013. Evaluation of fungicides for control of Botrytis fruit rot and leaf spot in strawberry, 2012. Plant Disease Management Reports 7:SMF009. Schilder, A. M. C., Gillett, J. M., and Sysak, R. W. 2013. Evaluation of fungicides for control of Botrytis bunch rot in grapes, 2012. Plant Disease Management Reports 7:SMF010. Schilder, A. M. C., Gillett, J. M., and Sysak, R. W. 2013. - Evaluation of fungicides for control of foliar and fruit diseases in Niagara grapes, 2012. Plant Disease Management Reports 7:SMF011. Schilder, A. M. C., Gillett, J. M., and Sysak, R. W. 2013. Evaluating fungicides and biocontrol products for control of fruit rots in blueberries, 2012. Plant Disease Management Reports 7:SMF012. Schilder, A. M. C., Gillett, J. M., and Sysak, R. W. 2013. Evaluating fungicides and biocontrol products for control of mummyberry in blueberries, 2012. Plant Disease Management Reports 7:SMF013. Schilder, A. M. C., Gillett, J. M., and Sysak, R. W. 2013. Evaluation of fungicide programs for control of powdery mildew in Chancellor grapes, 2012. Plant Disease Management Reports 7:SMF023. Schilder, A. M. C., Gillett, J. M., and Sysak, R. W. 2013. Control of powdery mildew in Chancellor grapes, 2011. Plant Disease Management Reports 7:SMF041. Schilder, A. M. C., Gillett, J. M., and Sysak, R. W. 2013. Evaluation of fungicides for control of foliar and fruit diseases in wine grapes, 2011. Plant Disease Management Reports 7:SMF042. Schilder, A. M. C., Gillett, J. M., and Sysak, R. W. 2013. Evaluation of fungicides for control of Botrytis bunch rot and powdery mildew in grapes, 2011. Plant Disease Management Reports 7:SMF043.
  • Type: Conference Papers and Presentations Status: Published Year Published: 2013 Citation: Schilder, A. 2013. Preparing and using mummy berry observation stations. MSU Extension News for Agriculture (http://news.msue.msu.edu/news/category/fruit). Posted on April 23, 2012. Schilder, A. 2013. Preparing and using mummy berry observation stations. New York Berry Newsletter 12 (5A): 9-11. Schilder, A. 2013. As bloom is approaching, focus on preventing diseases of the young fruit clusters. Michigan Grape and Wine Newsletter 3 (4): 2-6. Schilder, A. 2013. It is not too late for dormant sprays. Michigan Grape and Wine Newsletter 3 (1): 3-5. Schilder, A. 2013. It is not too late for dormant sprays. MSU Extension News for Agriculture (http://news.msue.msu.edu/news/category/fruit). Posted on April 23, 2012. Schilder, A. 2013. 2013 Fungicide update. Michigan Grape and Wine Newsletter 3 (1): 5-7.
  • Type: Conference Papers and Presentations Status: Published Year Published: 2013 Citation: Schilder, A., Gillett, J. M., Brown-Rytlewski, D., Sabbatini, P., and Endeshaw, S. 2013. Michigan small fruit virus update. WERA-20 Annual meeting, Kennewick, WA, 10 Sep, 2013. Schilder, A. M. C., and Gillett, J. M. 2013. Blueberry shock virus (BlShV) sampling efficiency and cold hardiness studies in blueberry. American Phytopathological Society Annual Meeting, August 10-14, 2013, Austin, TX (poster). Schilder, A. M. C., Miles, T. D, Gillett, J. M., and Jarosz, A. M. 2013. The effects of environmental factors on infection of blueberry fruit by Colletotrichum acutatum. American Phytopathological Society Annual Meeting, August 10-14, 2013, Austin, TX (poster). Schilder, A. M. C., Gillett, J. M., Sysak, R. W., and Vandervoort, C. 2013. Effect of rain on fungicide persistence and efficacy on grape leaves. 65th International Symposium on Crop Protection, Ghent, Belgium, 21 May, 2013.


Progress 01/01/12 to 12/31/12

Outputs
OUTPUTS: Conducted three blueberry trials to evaluate fungicide efficacy and phytotoxicity. Conducted six grape fungicide and cultural control efficacy trials. Monitored five vineyards for powdery and downy mildew for model validation. Conducted one strawberry and one raspberry fungicide efficacy trial. Completed a strawberry rotation crop trial for nematode control. Conducted a survey for grapevine virus diseases in 39 vineyards and conducted virus testing in tree blueberry fields. Completed a spatial analysis of two viruses in a vineyard. Sampled three blueberry fields intensively for a study on the etiology of bronze leaf curl (in collaboration with Bob Martin, USDA-ARS Corvallis, OR). Collaborated on a study on bunch rot control in grapes by leaf removal and disease management in tunnel-grown raspberries and cherries. Provided disease diagnosis and recommendations on small fruit disease management for growers, nurserymen, consultants and homeowners. Assisted MSU Diagnostic Services in diagnosing small fruit diseases. Collaborated with the Michigan Department of Agriculture in developing recommendations for blueberry virus management. Produced a promotional video of MSU research stations with emphasis on blueberry leaf rust. Made 36 presentations at grower meetings, workshops, and scientific conferences. Participated in 15 field days, conferences, workshops, and training events. Gave a guest lectures in course on Ecological Food and Farming systems and two guest lectures in Organic Pest Management Course. Organized two workshops. Results from trials were shared with growers and other stakeholders at field days, twilight meetings, training workshops as well as larger grower meetings (e.g., Great Lakes Expo in Grand Rapids, Viticulture Day). Articles were written in weekly or biweekly newsletters, such as the MSU Grape Newsletter, MSU Extension News website. Some of these articles were picked up by other newsletters, e.g., New York Berry Newsletter and Western Farm Press. PARTICIPANTS: In this project, we collaborate closely in research and extension activities with James Hancock (Small fruit breeder, Dept. Horticulture), Eric Hanson (Horticulturist, Dept. Horticulture), Greg Lang (Horticulturist, Dept. Horticulture), Paolo Sabbatini and Tom Zabadal (Viticulturist, Dept. Horticulture), Rufus Isaacs (small fruit Entomologist, Dept. Entomology), John Wise (Fruit Entomologist, Dept. Entomology), Jeff Andresen (Agrometeorologist, Dept. Geography), Matt Grieshop (Organic Pest Management Specialist, Dept. Entomology), Paul Jenkins (Grape Education Coordinator, Dept Entomology), Elliott Ryser (Dept. Food Science), Muraleedharan Nair (Dept. Horticulture), Randy Beaudry (Dept. Horticulture), Ray Hammerschmidt (Dept. Plant Pathology), Jan Byrne and Fred Warner (MSU Diagnostic Services), Mark Longstroth (MSU Extension, SW Michigan), Diane Brown- Rytlewski (MSU Extension, Berrien Co.), Bob Tritten (MSU Extension, Eastern Michigan), Carlos Garcia-Salazar (West-Central Michigan), and Nikki Rothwell (MSU NW Michigan Horticultural Research Center). The main research participants in this project were Jerri Gillett (Research Assistant), Roger Sysak (Research Technician), Timothy Miles (PhD student), Laura Avila (MS Student), Kasey Clemens (MS student), Brooke Anderson (PhD student), Randy Smith (assistant) and several undergraduate assistants who assisted in field and laboratory research activities. Experiments were conducted in fields of numerous small fruit growers in Michigan and in collaboration with personnel at the Trevor Nichols Research Center in Fennville, MI, the Clarksville Horticultural Research Center in Clarksville, MI, the Southwest Michigan Research and Extension Center in Benton Harbor, MI, and the Northwest Michigan Horticulture Research and Extension Center in Traverse City, MI, the MSU Horticulture Farm and MSU Plant Pathology Farm in East Lansing, MI. The project provided training opportunities to various MS and PhD students as well as undergraduate students. Partner organizations are the Michigan Blueberry Growers Association, Michigan State Horticultural Society, North American Strawberry Growers Association, National Grape Cooperative, Michigan Grape and Wine Industry Council, USDA-Corvallis (OR), Quebec Ministry of Agriculture, Fisheries & Food (MAPAQ), Canada; and independent berry growers. TARGET AUDIENCES: The primary target audience for the project is small fruit growers, nursery owners, extension personnel and private consultants in Michigan and the Great Lakes region. In addition, undergraduate and graduate students are being educated in small fruit disease diagnosis and management as part of this project. PROJECT MODIFICATIONS: No major project modification were made.

Impacts
A better understanding of the identity and biology of small fruit pathogens is helping growers use the most appropriate fungicides and optimize fungicide timing for disease control. Growers are using more environmentally friendly fungicides and more growers are starting to grow fruit organically. Data on the effects of diseases on plant growth, fruit yield and quality help growers in making control decisions. Studies on the environmental requirements for infection are forming the basis for disease-forecasting models that will use weather data to predict infection periods. This is anticipated to result in improved disease control and a concomitant reduction in fungicide applications. Efficacy testing of reduced-risk fungicides, biological control products, natural products, and inorganic substances has led to a diversification of disease control options and reduced the dependency of blueberry growers on conventional fungicides, including older products which are suspected carcinogens. As prices of certain fungicides increased, our efficacy data helped growers select and feel confident about alternative options. New information on fungicide resistance in grape powdery mildew strains is helping growers choose more effective fungicides and implement fungicide resistance management techniques. Our work on dormant sprays has resulted in many small fruit growers integrating dormant sprays into their program, lowering disease pressure during the growing season. New information on fungicide rainfastness and fungicide application efficiency is being applied immediately to improve fungicide timing and calibration and best use of fungicide sprayers. Identification of sources of host plant resistance, resistance mechanisms, and improved screening techniques is facilitating small fruit breeding efforts to develop resistant cultivars. New knowledge on cultivar resistance included in fact sheets and the Michigan Fruit Management Guide is also helping growers adjust their management strategies to the innate resistance in their cultivars. Evaluation of biocontrol agents and cultural practices on disease severity has helped growers choose management practices that are ecologically and biologically sound. Our research on virus diseases in grapes and blueberries has increased awareness of virus problems in small fruit crops, resulting in changes in management practices, such as increased use of certified virus-tested plant material. Our research also feeds information into the Berry Clean Plant Network which has been established to produce virus-free foundation stock to nurseries. Results from this project are expected to have environmental, worker, and consumer benefits by reducing chemical use in fruit production. The project helps to maintain short-term and long-term viability of small fruit production in the United States.

Publications

  • Schilder, A. 2012. Is late-season disease control needed in grapes Michigan Grape and Wine Newsletter 2 (9): 5-6.
  • Schilder, A. 2012. Pay attention to powdery mildew control in grapes. Michigan Grape and Wine Newsletter 2 (7):4-5.
  • Schilder, A. 2012. How to get the most out of your fungicide sprays. Michigan Grape and Wine Newsletter 2 (6): 5-7.
  • Schilder, A. 2012. Grape virus diagnostic support during the 2012 growing season. Michigan Grape and Wine Newsletter 2 (5): 5-6.
  • Schilder, A. 2012. Early-season scouting for diseases in vineyards: what to look for. Michigan Grape and Wine Newsletter 2 (4): 5-6.
  • Isaacs, R., and Schilder, A. 2012. Pest management considerations in frost-damaged vineyards. Michigan Grape and Wine Newsletter 2 (4): 6-9.
  • Isaacs, R., and Schilder, A. 2012. Pest management considerations in frost-damaged vineyards. Michigan Grape and Wine Newsletter 2 (3): 10-13.
  • Schilder, A. 2012. Late-season control of powdery mildew in grapes: focus on inoculum management. MSU Extension News for Agriculture (http://news.msue.msu.edu/news/ category/fruit). Posted on Sep 4, 2012.
  • Schilder, A. 2012. Banish bunch rots in grapes. MSU Extension News for Agriculture (http://news.msue.msu.edu/news/ category/fruit). Posted on Aug 21, 2012.
  • Schilder, A. 2012. Is late-season disease control needed in grapes MSU Extension News for Agriculture (http://news.msue.msu.edu/news/ category/fruit). Posted on July 24, 2012.
  • Schilder, A. 2012. Protect grape clusters from all major grape diseaseas. MSU Extension News for Agriculture (http://news.msue.msu.edu/news/category/fruit). Posted on June 12, 2012.
  • Schilder, A. 2012. Pay attention to powdery mildew in grapes. MSU Extension News for Agriculture (http://news.msue.msu.edu/news/category/fruit). Posted on 5 June, 2012.
  • Schilder, A. 2012. How to get the most out of your fungicide sprays on fruit crops. MSU Extension News for Agriculture (http://news.msue.msu.edu/news/category/fruit). Posted on 31 May, 2012.
  • Schilder, A. 2012. Bloom is a critical time for control of Botrytis gray mold in strawberries. MSU Extension News for Agriculture (http://news.msue.msu.edu/news/category/fruit). Posted on 15 May, 2012.
  • Schilder, A. 2012. Grape virus diagnostic support during the 2012 growing season. MSU Extension News for Agriculture (http://news.msue.msu.edu/news/category/fruit). Posted on 15 May, 2012.
  • Schilder, A. 2012. Protect against blossom blights in blueberries. MSU Extension News for Agriculture (http://news.msue.msu.edu/news/category/fruit). Posted on 1 May, 2012.
  • Schilder, A. 2012. Watch out for angular leaf spot in strawberries. MSU Extension News for Agriculture (http://news.msue.msu.edu/news/category/fruit). Posted on 1 May, 2012.
  • Isaacs, R., and Schilder, A. 2012. Pest management considerations in frost-damaged vineyards. MSU Extension News for Agriculture (http://news.msue.msu.edu/news/ category/fruit). Posted on Apr 19, 2012.
  • Schilder, A. 2012. 2012 fungicide update for grapes. MSU Extension News for Agriculture (http://news.msue.msu.edu/news/category/fruit). Posted on 10 April, 2012.
  • Schilder, A. 2012. Fungicide update for blueberries, 2012. MSU Extension News for Agriculture (http://news.msue.msu.edu/news/category/fruit). Posted on 27 March, 2012.
  • Ehm, C., and Schilder, A. M. C. 2012. TNRC promotional video. AgBioResearch, Michigan State University.
  • Schilder, A. M. C., and Gillett, J. M. 2012. Grapevine and blueberry viruses in Michigan. WERA-20 meeting, Sept. 17-19, 2012, Clemson, SC.
  • Schilder, A. M. C., and Gillett, J. M. 2012.Rainfastness of fungicides on grape leaves. American Phytopathological Society Annual Meeting, August 4-8, 2011, Providence, RI (meeting abstract).
  • Miles, T. D., and Schilder, A. M. C. Infection of blueberries by Colletotrichum acutatum: Host defenses, inheritance of resistance, and environmental effects. American Phytopathological Society Annual Meeting, August 4-8, 2011, Providence, RI (Melhus Symposium invited presentation) (meeting abstract).
  • Schilder, A. M. C., Miles, T. D., Gillett, J. M., and Sysak, R. W. 2012. Observations on blueberry leaf rust, caused by Thekopsora minima, in Michigan. American Phytopathological Society Annual Meeting, August 4-8, 2011, Providence, RI (meeting abstract).
  • Schilder, A. M. C., Miles, L. A., Miles, T. D., and Kirk, W. D. 2012. Strobilurin (QoI) resistance in populations of Erysiphe necator on Grapes in Michigan. American Society for Enology and Viticulture- Eastern Section Meeting, Traverse City, July 16-18, 2012 (meeting abstract).
  • Schilder, A. M. C., and Gillett, J. M. 2012. Diagnosis of grapevine virus diseases in Michigan vineyards. American Society for Enology and Viticulture- Eastern Section Meeting, Traverse City, July 16-18, 2012 (meeting abstract).
  • Schilder, A. M. C., Miles, L. A., Powers, K. L., Rothwell, N. L. 2012. Late-season chasmothecium production and dispersal of Erysiphe necator in Michigan. American Society for Enology and Viticulture- Eastern Section Meeting, Traverse City, July 16-18, 2012 (meeting abstract).
  • Schilder, A. M. C., Chemical differences between fruit of an anthracnose fruit rot-resistant and susceptible cultivar. 10th International Symposium on Vaccinium and Other Superfruits. June 17-21, 2012, Maastricht, The Netherlands (meeting abstract).
  • Schilder, A. M. C., Miles, T. D., and Hancock, J. F. 2012. Inheritance of anthracnose fruit rot resistance in highbush blueberry. 10th International Symposium on Vaccinium and Other Superfruits. June 17-21, 2012, Maastricht, The Netherlands (meeting abstract).
  • Schilder, A. M. C., Gillett, J. M., and Sysak, R. W. 2012. Prospects for biological control of blueberry diseases. 10th International Symposium on Vaccinium and Other Superfruits. June 17-21, 2012, Maastricht, The Netherlands (meeting abstract).
  • Miles, L. A., Miles, T. D., Kirk, W. W., and Schilder, A. M. C. 2012. Screening for strobilurin (QoI) resistance in populations of Erysiphe necator on grapes in Michigan. Plant Disease 96: 1621-1628.
  • Rouxel, M., Mestre, P., Comont, G., Lehman, B., Schilder, A., and Delmotte, F. 2012. Phylogenetic and experimental evidence for host-specialized cryptic species in Plasmopara viticola. New Phytologist 197: 251-263.
  • Grieshop, M., Hanson, E., Schilder, A., Isaacs, R., Mutch, D., Garcia-Salazar, C., Longstroth, M., Sadowsky, J. 2012. Status update on organic blueberries in Michigan. International Journal of Fruit Science 12:232-245.
  • Sadowsky, J. J., Schilder, A. M. C., and Hanson, E. J. 2012. Root colonization by ericoid mycorrhizae and dark septate endophytes in organic and conventional blueberry fields in Michigan. International Journal of Fruit Science, 12:169-187.
  • Wise, J. C., Gut, L. J., Isaacs, R., Schilder, A. M. C., Sundin, G. W., Zandstra, B., Hanson, E., and Shane, B. 2012. Michigan Fruit Management Guide 2013. Extension Bulletin E-154. Michigan State University, East Lansing, MI. 302 pp.
  • Schilder, A. Wine grape season shaping up for powdery mildew. Western Farm Press. June 12, 2012. http://westernfarmpress.com/grapes/wine-grape-season-shaping-powdery- mildew.
  • Schilder, A. 2012. Overview of grape diseases during the 2012 growing season. Michigan Grape and Wine Newsletter 2 (14): 4-5.
  • Schilder, A. 2012. Last chance to participate in grape virus diagnostic survey. Michigan Grape and Wine Newsletter 2 (13): 5.
  • Schilder, A. 2012. Recent observations of disease and other symptoms in grape vineyards. Michigan Grape and Wine Newsletter 2 (12): 3-4.
  • Schilder, A. 2012. Late-season sprays and potential effects on fermentation. Michigan Grape and Wine Newsletter 2 (12): 5-6.
  • Schilder, A. 2012. Disease monitoring at harvest. Michigan Grape and Wine Newsletter 2 (12): 6.
  • Schilder, A. 2012. Late-season control of powdery mildew in grapes: focus on inoculum management. Michigan Grape and Wine Newsletter 2 (11): 9-11.
  • Schilder, A. 2012. Banish bunch rots in grapes. Michigan Grape and Wine Newsletter 2 (10): 4-5.


Progress 01/01/11 to 12/31/11

Outputs
OUTPUTS: Conducted 5 blueberry fungicide efficacy trials. Monitored 8 blueberry fields weekly for mummy berry through bloom. Conducted 6 grape fungicide and cultural control efficacy trials. Conducted disease threshold trials in 2 vineyards. Monitored 5 vineyards for powdery and downy mildew for model validation. Conducted 2 strawberry fungicide efficacy trials. Conducted a strawberry rotation crop trial for nematode control. Conducted a survey for grapevine virus diseases in 10 vineyards. EvaluatedConducted virus testing in 6 blueberry fields and nurseries. Sampled three blueberry intensively for new viruslike disease (bronze leaf curl) for study of etiology (in collaboration with Bob Martin, USDA-ARS Corvallis, OR). Assisted in sampling strawberry fields for viruses for Bob Martin, USDA-ARS Corvallis, OR. Provided disease diagnosis and recommendations on small fruit disease management for growers, nurserymen, consultants and homeowners. Assisted MSU Diagnostic Services in diagnosing small fruit diseases. Collaborated with the Michigan Department of Agriculture in developing recommendations for blueberry virus management. Produced two new regional Pest Alert fact sheets on exotic blueberry viruses (in collaboration with NC IPM Center).Produced a new fact sheet on Phomopsis twig blight and canker in blueberries. Published a revision of the Grape Pocket IPM Scouting Guide. Produced a video on scouting for and management of fruit rot diseases in grapes. Made 39 presentations at grower meetings, workshops, and scientific conferences. Participated in 27 field days, conferences, workshops, and training events. Co-taught 1 course on Ecological Food and Farming systems and gave two guest lectures in Organic Pest Management Course. Led a field trip in Plant Diseases in the Field course. Developed a prediction model for anthracnose fruit rot in blueberries, which was incorporated in the MSU EnviroWeather system. Results from trials were shared with growers and other stakeholders via field days, twilight meetings, training workshops as well as larger grower meetings (e.g., Great Lakes Expo in Grand Rapids, New England Fruit and Vegetable Conference in New Hampshire, and Journees Horticoles in Quebec). Articles were written in weekly or biweekly newsletters, such as the MSU Grape Newsletter and Blueberry Newletter, MSU Extension News website. Some of these articles were picked up by other newsletters, e.g., New York Berry Newsletter. PARTICIPANTS: In this project, we collaborate closely in research and extension activities with James Hancock (Small fruit breeder, Dept. Horticulture), Eric Hanson (Horticulturist, Dept. Horticulture), Greg Lang (Horticulturist, Dept. Horticulture), Paolo Sabbatini and Tom Zabadal (Viticulturist, Dept. Horticulture), Rufus Isaacs (small fruit Entomologist, Dept. Entomology), John Wise (Fruit Entomologist, Dept. Entomology), Jeff Andresen (Agrometeorologist, Dept. Geography), Matt Grieshop (Organic Pest Management Specialist, Dept. Entomology), Paul Jenkins (Grape Education Coordinator, Dept Entomology), Elliott Ryser (Dept. Food Science), Muraleedharan Nair (Dept. Horticulture), Randy Beaudry (Dept. Horticulture), Ray Hammerschmidt (Dept. Plant Pathology), Jan Byrne and Fred Warner (MSU Diagnostic Services), Mark Longstroth (MSU Extension, SW Michigan), Diane Rytlewski-Brown (MSU Extension, Berrien Co.), Bob Tritten (MSU Extension, Eastern Michigan), and Carlos Garcia-Salazar (West-Central Michigan), and Nikki Rothwell (MSU NW Michigan Horticultural Research Center). The main research participants in this project were Jerri Gillett (Research Assistant), Roger Sysak (Research Technician), Timothy Miles (PhD student), Laura Avila (MS Student), Srdjan Acimovic (PhD student), Patrick Gaulier (assistant), Randy Smith (assistant) and several undergraduate assistants who assisted in the field and laboratory research activities. Experiments were conducted in fields of numerous small fruit growers in Michigan and in collaboration with personnel at the Trevor Nichols Research Center in Fennville, MI, the Clarksville Horticultural Research Center in Clarksville, MI, the Southwest Michigan Research and Extension Center in Benton Harbor, MI, and the Northwest Michigan Horticulture Research and Extension Center in Traverse City, MI, the MSU Horticulture Farm and MSU Plant Pathology Farm in East Lansing, MI. The project provided training opportunities to various MS and PhD students as well as undergraduate students. Partner organizations are the Michigan Blueberry Growers Association, Michigan State Horticultural Society, North American Strawberry Growers, National Grape Cooperative, Michigan Grape and Wine Industry Council, INRA in France, and independent berry growers. TARGET AUDIENCES: The primary target audience for the project is small fruit growers and nursery owners in Michigan and other Great Lakes states as well as extension personnel and private consultants. In addition, undergraduate and graduate students are being educated in small fruit disease diagnosis and management as part of this project. PROJECT MODIFICATIONS: There were no major modifications to the project approach.

Impacts
A better understanding of the identity and biology of small fruit pathogens is helping growers use the most appropriate fungicides and optimize fungicide timing for disease control. Growers are using more environmentally friendly fungicides and more growers are starting to grow fruit organically. Data on the effects of diseases on plant growth, fruit yield and quality help growers in making control decisions. Studies on the environmental requirements for infection are forming the basis for disease-forecasting models that will use weather data to predict infection periods. This is anticipated to result in improved disease control and a concomitant reduction in fungicide applications. Efficacy testing of reduced-risk fungicides, biological control products, natural products, and inorganic substances has lead to a diversification of disease control options and reduce the dependency of blueberry growers on conventional fungicides, including older products which are suspected carcinogens. As prices of certain fungicides increased, our efficacy data helped growers select and feel confident about alternative options. New information on fungicide resistance in grape powdery mildew strains is helping growers choose more effective fungicides and implement fungicide resistance management techniques. New information on fungicide rainfastness and fungicide application efficiency is being applied immediately to improve fungicide timing and calibration and best use of fungicide sprayers. Identification of sources of host plant resistance, resistance mechanisms, and improved screening techniques is facilitating small fruit breeding efforts to develop resistant cultivars. New knowledge on cultivar resistance included in new fact sheets and the Michigan Fruit Management Guide is also helping growers adjust their management strategies to the innate resistance in their cultivars. Evaluation of biocontrol agents and cultural practices on disease severity will help growers choose management practices that are ecologically and biologically sound. Results from this project are expected to have environmental, worker, and consumer benefits by reducing chemical use in fruit production. This project helps to maintain short-term and long-term viability of small fruit production in the United States.

Publications

  • Schilder, A. 2011. Mid-summer grape disease update. MSU Extension News for Agriculture (http://news.msue.msu.edu/news/category/fruit). Posted on 12 July 2011.
  • Schilder, A. 2011. Dont let downy mildew get you down. MSU Extension News for Agriculture (http://news.msue.msu.edu/news/category/fruit). Posted on 28 Jun 2011.
  • Schilder, A. 2011. Keep an eye on anthracnose infection risk model for blueberries. MSU Extension News for Agriculture (http://news.msue.msu.edu/news/category/fruit). Posted on 21 June 2011.
  • Schilder, A. 2011. Regional Pest Alerts on blueberry virus. MSU Extension News for Agriculture (http://news.msue.msu.edu/news/category/fruit). Posted on 21 June 2011.
  • Schilder, A. 2011. Preventing grape Phomopsis infection of rachis and fruit. MSU Extension News for Agriculture (http://news.msue.msu.edu/news/category/fruit). Posted on 14 June 2011.
  • Schilder, A. 2011. Managing black rot on grapes. MSU Extension News for Agriculture (http://news.msue.msu.edu/news/category/fruit). Posted on 14 June 2011.
  • Schilder, A. 2011. Protect grape clusters from powdery mildew and downy mildew. MSU Extension News for Agriculture (http://news.msue.msu.edu/news/category/fruit). Posted on 14 June 2011.
  • Schilder, A. 2011. Anthracnose: How to recognize and control this fungal disease of grapevines. MSU Extension News for Agriculture (http://news.msue.msu.edu/news/category/fruit). Posted on 14 June 2011.
  • Schilder, A. 2011. Keep an eye on angular leaf spot in strawberries. MSU Extension News for Agriculture (http://news.msue.msu.edu/news/category/fruit). Posted on 31 May 2011.
  • Schilder, A. 2011. Phytophthora diseases a threat to strawberries during excessively wet conditions. MSU Extension News for Agriculture (http://news.msue.msu.edu/news/category/fruit). Posted on 25 May 2011.
  • Schilder, A. 2011. Bloom is a critical time to control Botrytis gray mold in strawberries. MSU Extension News for Agriculture (http://news.msue.msu.edu/news/category/fruit). Posted on 25 May 2011.
  • Schilder, A. 2011. The challenges of disease control during rainy spells. MSU Extension News for Agriculture (http://news.msue.msu.edu/news/category/fruit). Posted on 24 May 2011.
  • Schilder, A. 2011. QuiltXcel: a new fungicide for berry crops. MSU Extension News for Agriculture (http://news.msue.msu.edu/news/category/fruit). Posted on 10 May 2011.
  • Schilder, A. 2011. Spring grape disease management: what to consider. MSU Extension News for Agriculture (http://news.msue.msu.edu/news/category/fruit). Posted on 6 May 2011.
  • Schilder, A. 2011. Mummy berry nurseries facilitate scouting for apothecia. MSU Extension News for Agriculture (http://news.msue.msu.edu/news/category/fruit). Posted on 4 May 2011.
  • Schilder, A. 2011. Fungicide update for blueberries. MSU Extension News for Agriculture (http://news.msue.msu.edu/news/category/fruit). Posted on 3 May 2011.
  • Schilder, A. 2011. Anthracnose infection risk model launched on Enviro-weather. MSU Extension News for Agriculture (http://news.msue.msu.edu/news/category/fruit). Posted on 25 May 2011.
  • Schilder, A. 2011. Newer fungicide chemistries for grapes. MSU Extension News for Agriculture (http://news.msue.msu.edu/news/category/fruit). Posted on 26 April 2011.
  • Schilder, A. 2011. There is still time for dormant sprays in grapes. MSU Extension News for Agriculture (http://news.msue.msu.edu/news/category/fruit). Posted on 26 April 2011.
  • Schilder, A. 2011. Scouting and management of mummy berry in blueberries. MSU Extension News for Agriculture (http://news.msue.msu.edu/news/category/fruit). Posted on 12 April 2011.
  • Isaacs, R., Schilder, A., Zabadal, T., and Weigle. T. 2011. A pocket guide for grape IPM scouting in the North Central and Eastern U.S., 4th Edition. Michigan State University Extension Bulletin E-2889.
  • Schilder, A., 2011. Phomopsis canker and twig blight. Michigan Blueberry Facts. Michigan State University Extension Bulletin (in press).
  • Schilder, A. 2011. Blueberry Scorch Virus. Regional Pest Alert, NC IPM Center, Urbana, IL.
  • Schilder, A. 2011. Blueberry Shock Virus. Regional Pest Alert, NC IPM Center, Urbana, IL.
  • Miles, T. D, Callow, P., Hancock, J., and Schilder, A. M. C. 2011. Evaluation of different inoculation techniques and fruit characteristics in relation to resistance to anthracnose fruit rot in blueberry. Plant Pathology DOI: 10.1111/j.1365-3059.2011.02541.x.
  • Schilder, A. M. C., Gillett, J. M., and Sysak, R. W. 2010. Evaluation of fungicides for control of powdery mildew and downy mildew in wine grapes. Plant Disease Management Reports 4:SMF034.
  • Schilder, A. 2011. Leaf rust spotted in Michigan blueberry fields. MSU Extension News for Agriculture (http://news.msue.msu.edu/news/category/fruit). Posted on 6 September, 2011.
  • Schilder, A. 2011. Brrrr, black root rot in strawberries. MSU Extension News for Agriculture (http://news.msue.msu.edu/news/category/fruit). Posted on 23 August 2011.
  • Schilder, A. 2011. Management of botrytis gray mold in fall raspberries. MSU Extension News for Agriculture (http://news.msue.msu.edu/news/category/fruit). Posted on 23 August 2011.
  • Hanson, E., Von Weihe, M., Schilder, A. C., Chanon, A. M., and Scheerens, J. C. 2011. High tunnel and open field production of floricane- and primocane-fruiting raspberry cultivars. HortTechnology 21:412-418.
  • Sadowsky, J. J., Miles, T. D., and Schilder, A. M. C. 2011. First report of stem rot caused by Calonectria colhounii (anamorph: Cylindrocladium colhounii) on greenhouse-grown blueberries in the United States. Plant Disease 95:1187 DOI: 10.1094/PDIS-02-11-0117.
  • Miles, T. D., Woelk, C. I., Rojas, A., and Schilder, A. M. C. 2011. First report of Pythium sterilum causing root rot of blueberry in the United States. Plant Disease 95:614.
  • Schilder, A. M. C., Lizotte, E. L., Yun, H. Y., Dixon, L. J., and Castlebury, L. J. 2011. First report of juneberry rust caused by Gymnosporangium nelsonii on juneberry in Michigan. Plant Disease 95:770, DOI: 10.1094/PDIS-12-10-0874.
  • Schilder, A. M. C., and Miles, T. D. 2011. First report of blueberry leaf rust caused by Thekopsora minima on Vaccinium corymbosum in the United States. Plant Disease 95:768.
  • Schilder, A. M. C., Gillett, J. M., and Sysak, R. W. 2010. Efficacy of fungicide programs incorporating phosphites against downy mildew and Phomopsis in Niagara grapes, 2008. Plant Disease Management Reports 4:SMF035.
  • Schilder, A. M. C., Gillett, J. M., and Sysak, R. W. 2010. Evaluation of fungicides for control of diseases in red raspberries, 2008. Plant Disease Management Reports 4:SMF049.
  • Schilder, A. 2011. Control of pre- and post-harvest fruit rots in blueberries. MSU Extension News for Agriculture (http://news.msue.msu.edu/news/category/fruit). Posted on 26 July 2011.
  • Miles, T. D, Day, B., and Schilder, A. M. C. 2011. Identification of differentially expressed genes in a resistant versus a susceptible blueberry cultivar after infection by Colletotrichum acutatum. Molecular Plant Pathology 12: 463-477.


Progress 01/01/10 to 12/31/10

Outputs
OUTPUTS: Conducted 3 blueberry fungicide efficacy trials Monitored 5 blueberry fields weekly for diseases throughout the season, and 3 additional locations with mummy berry nurseries through bloom Conducted 6 grape fungicide efficacy trials Conducted disease threshold trials in 7 vineyards. Monitored 5 vineyards for powdery and downy mildew Conducted 2 strawberry fungicide efficacy trials Conducted a raspberry fungicide efficacy trial Established a new raspberry and grape research planting Conducted a strawberry rotation crop trial for nematode control Conducted a survey for grapevine virus diseases in 10 vineyards Conducted a study of dagger nematodes and TRSV and ToRSV in 5 blueberry fields Provided disease diagnosis and consulting on disease management in over 15 cases. Produced a new fact sheet on blueberry rust. Made 23 presentations at grower meetings, workshops, and conferences. Co-organized the North American Research and Extension Workers (NABREW) conference. Updated and expanded information on two websites (www.blueberries.msu.edu and www.grapes.msu.edu). PARTICIPANTS: In this project, we are collaborating closely in terms of research and extension activities with James Hancock (Small fruit breeder, Dept. Horticulture), Eric Hanson (Horticulturist, Dept. Horticulture), Tom Zabadal (Viticulturist, Dept. Horticulture), Rufus Isaacs (small fruit Entomologist, Dept. Entomology), John Wise (Fruit Entomologist, Dept. Entomology), Jeff Andresen (Agrometeorologist, Dept. Geography), Matt Grieshop (Organic Pest Management Specialist, Dept. Entomology), Paul Jenkins (Grape and Blueberry Education Coordinator, Dept Entomology), Stuart Grandy (Soil Biologist, Dept. Horticulture), Elliott Ryser (Dept. Food Science), Muraleedharan Nair (Dept. Horticulture), Randy Beaudry (Dept. Horticulture), Brad Day (Dept. Plant Pathology), Ray Hammerschmidt (Dept. Plant Pathology), Mark Longstroth (MSU Extension, SW Michigan), Diane Rytlewski-Brown (MSU Extension, Berrien Co.), Bob Tritten (MSU Extension, Eastern Michigan), and Carlos Garcia-Salazar (West-Central Michigan).The main research participants in this project were Jerri Gillett (Research Assistant), Roger Sysak (Research Technician), Timothy Miles (PhD student), Laura Avila (MS Student), Jesse Sadowsky (MS Student), Srdjan Acimovic (PhD student), Amber Townes (MS Student), Patrick Gaulier (assistant), Randy Smith (assistant) and several undergraduate assistants who conducted the field and laboratory research activities with assistance from undergraduate students. Experiments were conducted in fields of numerous small fruit growers in Michigan and in collaboration with personnel at the Trevor Nichols Research Complex in Fennville, MI, the Clarksville Horticultural Experiment Station in Clarksville, MI, the Southwest Michigan Research and Extension Center in Benton Harbor, MI, and the Northwest Michigan Horticulture Research and Extension Station in Traverse City, MI, the MSU Horticulture Farm and MSU Plant Pathology Farm in East Lansing, MI. The project provided training opportunities to various MS and PhD students as well as undergraduate students. Partner organizations are the Michigan Blueberry Growers Association, Michigan State Horticultural Society, North American Strawberry Growers, National Grape Cooperative, Michigan Grape and Wine Industry Council, and independent berry growers. TARGET AUDIENCES: The primary target audience for the project is small fruit growers in Michigan and other Great Lakes states as well as extension personnel and private consultants. In addition, undergraduate and graduate students are being educated in small fruit diseases as part of this project. PROJECT MODIFICATIONS: There were no major modifications to the project approach.

Impacts
A better understanding of the identity and biology of small fruit pathogens is helping growers use the most appropriate fungicides and optimize fungicide timing for disease control. Growers are using more environmentally friendly fungicides and more growers are starting to grow fruit organically. Data on the effects of diseases on plant growth, fruit yield and quality help growers in making control decisions. Studies on the environmental requirements for infection are forming the basis for disease-forecasting models that will use weather data to predict infection periods. This is anticipated to result in a reduction in fungicide applications and improved disease control. Efficacy testing of reduced-risk fungicides, biological control products, natural products, and inorganic substances has lead to a diversification of disease control options and reduce the dependency of blueberry growers on conventional pesticides, including suspected carcinogens. As prices of certain fungicides increased, our efficacy data helped growers select and feel confident about alternative options. Identification of sources of host plant resistance and resistance mechanisms will facilitate small fruit breeding efforts to develop resistant cultivars, and will help growers adjust their management strategies to the innate resistance in their cultivars. Evaluation of biocontrol agents and cultural practices on disease severity will help growers choose management practices that are ecologically and biologically sound. Results from this project are expected to have environmental, worker, and consumer benefits by reducing chemical use in fruit production. The project will also help maintain short-term and long-term viability of small fruit production in the United States.

Publications

  • Wise, J. C., Schilder, A. M. C., Jenkins, P. E., Vandervoort, C., and Isaacs, R. 2010. Sprayer type and water volume influence pesticide deposition of grape clusters and control of insect pests and diseases in juice grapes. Crop Protection 29:378-385.
  • Sadowsky, J. J., Schilder, A. M. C., and Hanson, E. C. 2010. Root colonization by mycorrhizae and dark septate endophytes in organic and conventional blueberry fields in Michigan. International Journal of Fruit Science (in press).
  • Grieshop, M., Hanson, E., Schilder, A., Isaacs, R., Mutch, D., Garcia-Salazar, C., Longstroth, M., and Sadowsky, J. 2010. Status Update on Organic Blueberries in Michigan. International Journal of Fruit Science (in press).
  • Wise, J. C., Gut, L. J., Isaacs, R., Schilder, A. M. C., Sundin, G. W., Zandstra, B., Hanson, E., and Shane, B. 2010. Michigan Fruit Management Guide 2011. Extension Bulletin E-154. Michigan State University, East Lansing, MI.
  • Schilder, A. 2010. Generic fungicide options. Fruit Crop Advisory Team Alert Newsletter (http://ipmnews.msu.edu/fruit/) 25 (1): 2-3. Posted March 30, 2010.
  • Schilder, A. 2010. New fungicides for small fruit crops in Michigan. Fruit Crop Advisory Team Alert Newsletter (http://ipmnews.msu.edu/fruit/) 25 (1): 3-5. Posted March 30, 2010.
  • Schilder, A. 2010. Remember to scout for mummy berry in blueberries. Fruit Crop Advisory Team Alert Newsletter (http://ipmnews.msu.edu/fruit/) 25 (1):5. Posted March 30, 2010.
  • Schilder, A. 2010. There is still time for a delayed dormant spray against Phomopsis in grapes. Fruit Crop Advisory Team Alert Newsletter (http://ipmnews.msu.edu/fruit/) 25 (3):2-3. Posted April 27, 2010.
  • Schilder, A. 2010. First mummy berry shoot strikes spotted in blueberry fields. Fruit Crop Advisory Team Alert Newsletter (http://ipmnews.msu.edu/fruit/) 25 (3):3. Posted April 27, 2010.
  • Schilder, A. 2010. Revus Top, a new cost-effective fungicide for grapes. Fruit Crop Advisory Team Alert Newsletter (http://ipmnews.msu.edu/fruit/) 25 (7):2-3. Posted May 25, 2010.
  • Schilder, A. 2010. Revus Top, a new cost-effective fungicide for grapes. Fruit Crop Advisory Team Alert Newsletter (http://ipmnews.msu.edu/fruit/) 25 (7):2-3. Posted May 25, 2010.
  • Rosenbaum, R., and Schilder, A. 2010. Update on 2010 statewide survey for blueberry scorch and shock diseases. Fruit Crop Advisory Team Alert Newsletter (http://ipmnews.msu.edu/fruit/) 25 (10):5-6. Posted June 15, 2010.
  • Schilder, A. 2010. Cane anthracnose found in some blueberry fields. Fruit Crop Advisory Team Alert Newsletter (http://ipmnews.msu.edu/fruit/) 25 (12): 5-6. Posted June 29, 2010.
  • Schilder, A. 2010. Viticure, a fungicide specific for grapes. Fruit Crop Advisory Team Alert Newsletter (http://ipmnews.msu.edu/fruit/) 25 (12): 6-7. Posted June 29, 2010.
  • Schilder, A. 2010. Beware of blueberry leaf rust. Fruit Crop Advisory Team Alert Newsletter (http://ipmnews.msu.edu/fruit/) 25 (14): 2. Posted July 13, 2010.
  • Schilder, A. 2010. Don't let downy mildew get you down. Fruit Crop Advisory Team Alert Newsletter (http://ipmnews.msu.edu/fruit/) 25 (14): 2-4. Posted July 13, 2010.
  • Schilder, A. 2010. Controlling Botrytis bunch rot in grapes. Fruit Crop Advisory Team Alert Newsletter (http://ipmnews.msu.edu/fruit/) 25 (15): 6-7. Posted Aug 10, 2010.
  • Schilder, A. 2010. Don't let downy mildew get you down. Fruit Crop Advisory Team Alert Newsletter (http://ipmnews.msu.edu/fruit/) 25 (15): 5-6. Posted Aug 10, 2010.
  • Schilder, A., and Rosenbaum, R. 2010. Update on 2010 statewide survey for blueberry scorch and blueberry shock diseases. Fruit Crop Advisory Team Alert Newsletter (http://ipmnews.msu.edu/fruit/) 25 (16): 4-5. Posted Aug 24, 2010.
  • Schilder, A. 2010. Disease control after spring freeze injury in grapes: what are the options Fruit Crop Advisory Team Alert Newsletter (http://ipmnews.msu.edu/fruit/) 25 (7):3-4. Posted May 25, 2010.
  • Schilder, A. 2010. Regalia, a new fungicide for organic and conventional disease control. Fruit Crop Advisory Team Alert Newsletter (http://ipmnews.msu.edu/fruit/) 25 (9):16. Posted June 8, 2010.
  • Schilder, A. 2010. Phytotoxicity of Revus Top on Concord grapes. Fruit Crop Advisory Team Alert Newsletter (http://ipmnews.msu.edu/fruit/) 25 (9):15-16. Posted June 8, 2010.
  • Schilder, A. 2010. Angular leaf spot showing up in strawberries. Fruit Crop Advisory Team Alert Newsletter (http://ipmnews.msu.edu/fruit/) 25 (10): 3. Posted June 15, 2010.
  • Schilder, A. 2010. Fungicide properties and weather conditions. Fruit Crop Advisory Team Alert Newsletter (http://ipmnews.msu.edu/fruit/) 25 (10): 3-5. Posted June 15, 2010.
  • Schilder, A. 2010. How to recognize Phytophthora and Pythium root rot in blueberries. Fruit Crop Advisory Team Alert Newsletter (http://ipmnews.msu.edu/fruit/) 25 (16): 10-11. Posted Aug 24, 2010.
  • Schilder, A. 2010. Overview of small fruit diseases during the 2010 growing season. Fruit Crop Advisory Team Alert Newsletter (http://ipmnews.msu.edu/fruit/). Posted on 23 Sep, 2010.
  • Schilder, A. 2010. Watch out for angular leaf spot of strawberries. Fruit Crop Advisory Team Alert Newsletter (http://ipmnews.msu.edu/fruit/) 25 (5):11. Posted May 11, 2010.
  • Schilder, A. 2010. Use strobilurin fungicides wisely to avoid fungicide resistance development. Fruit Crop Advisory Team Alert Newsletter (http://ipmnews.msu.edu/fruit/) 25 (5):5-6. Posted May 11, 2010.
  • Miles, T., and Schilder, A. 2010. Keep scouting blueberries for disease symptoms. Fruit Crop Advisory Team Alert Newsletter (http://ipmnews.msu.edu/fruit/) 25 (5):6-7. Posted May 11, 2010.
  • Schilder, A. 2010. Cold, rainy weather increases risk of blossom and twig blight in blueberries. Fruit Crop Advisory Team Alert Newsletter (http://ipmnews.msu.edu/fruit/) 25 (5):7. Posted May 11, 2010.
  • Schilder, A. 2010. Anthracnose fruit rot prediction model. Fruit Crop Advisory Team Alert Newsletter (http://ipmnews.msu.edu/fruit/) 25 (6):13-14. Posted May 18, 2010.


Progress 01/01/09 to 12/31/09

Outputs
OUTPUTS: Conducted 6 blueberry fungicide efficacy trials; Monitored 5 blueberry fields weekly for diseases throughout the season; Conducted 5 grape fungicide efficacy trials; Conducted disease threshold trials in 2 vineyards. Monitored 6 vineyards for powdery and downy mildew. Conducted a raspberry fungicide efficacy trial. Established a new raspberry research planting. Conducted 2 strawberry fungicide efficacy trials. Conducted a strawberry rotation crop trial for nematode control. Conducted a survey for grapevine trunk diseases in 10 vineyards. Conducted a survey for fungicide resistance in 20 vineyards. Provided disease diagnosis and consulting on disease management in over 20 cases. Made presentations at 22 grower meetings, workshops, and conferences. Organized one workshop (WERA-20). Developed a disease prediction model for anthracnose fruit rot in blueberry which will be incorporated in the Michigan STate University EnviroWeather website. Updated and expanded information on two websites (www.blueberries.msu.edu and www.grapes.msu.edu). PARTICIPANTS: In this project, we are collaborating closely in terms of research and extension activities with James Hancock (Small fruit breeder, Dept. Horticulture), Eric Hanson (Horticulturist, Dept. Horticulture), Tom Zabadal (Viticulturist, Dept. Horticulture), Rufus Isaacs (small fruit Entomologist, Dept. Entomology), John Wise (Fruit Entomologist, Dept. Entomology), Jeff Andresen (Agrometeorologist, Dept. Geography), Matt Grieshop (Organic Pest Management Specialist, Dept. Entomology), Paul Jenkins (Grape and Blueberry Education Coordinator, Dept Entomology), Stuart Grandy (Soil Biologist, Dept. Horticulture), Elliott Ryser (Dept. Food Science), Muraleedharan Nair (Dept. Horticulture), Mark Longstroth (MSU Extension, SW Michigan), Bob Tritten (MSU Extension, Eastern Michigan), and Carlos Garcia-Salazar (West-Central Michigan).The main research participants in this project were Jerri Gillett (Research Assistant), Roger Sysak (Research Technician), Timothy Miles (PhD student), Laura Avila (MS Student), Jesse Sadowsky (MS Student), Patrick Gaulier (assistant) who conducted the field and laboratory research activities with assistance from undergraduate students. Experiments were conducted in fields of numerous small fruit growers in Michigan and in collaboration with personnel at the Trevor Nichols Research Complex in Fennville, MI, the Clarksville Horticultural Experiment Station in Clarksville, MI, the Southwest Michigan Research and Extension Center in Benton Harbor, MI, and the Northwest Michigan Horticulture Research and Extension Station in Traverse City, MI, the MSU Horticulture Farm and MSU Plant Pathology Farm in East Lansing, MI. The project provided training opportunities to various MS and PhD students as well as undergraduate students. Partner organizations are the Michigan Blueberry Growers Association, Michigan State Horticultural Society, North American Strawberry Growers, National Grape Cooperative, Michigan Grape and Wine Industry Council, and independent berry growers. TARGET AUDIENCES: The primary target audience for the project is small fruit growers in Michigan and other Great Lakes states as well as researchers, extension personnel and private consultants. PROJECT MODIFICATIONS: Nothing significant to report during this reporting period.

Impacts
Two new virus diseases were identified in Michigan blueberries in 2009: blueberry scorch and blueberry shock, as well as a disease of unknown etiology: blueberry bronze leaf curl. A survey showed that tomato ringspot virus and tobacco ringspot virus were the most common viruses in blueberries in Michigan. We also identified Phytophthora root rot in blueberries for the first time. We continued to evaluate scouting methods for mummy berry to demonstrate the benefits of scouting for disease management in highbush blueberries. The number of apothecia had the strongest correlation with disease symptoms. A video monitoring study showed that flies and mosquitoes visited shoot strikes more often than bees, which suggests that these may play a more important role in disease spread than previously thought. We developed a disease prediction model for blueberry anthracnose based on temperature and fruit wetness duration. The model was validated in two field trials in 2009. The 6- and 12-hour wetness duration thresholds worked well and resulted in 1 to 2 fewer sprays compared to a calendar-based spray schedule from bloom to harvest. Field studies of biofungicides showed good control by Serenade of mummy berry, Regalia (giant knotweed extract), GantecGold and Sporan (clove oil, thyme oil). In grapes, we identified grapevine leafroll virus, rupestris stempitting virus, and esca for the first time. In fungicide efficacy trials, Stylet Oil, Sulforix, and Kaligreen eradicated powdery mildew well. Serenade and Sonata also worked well against black rot, Phomopsis, downy mildew, and powdery mildew. Removal of infected canes and clusters also reduced black rot and Phomopsis. Leaf removal was one of the best strategies to control bunch rots. In a strawberry on-farm demonstration trial, Abound applied through the irrigation system and Vigor-Cal-Phos applied as a foliar spray reduced Rhizoctonia infection of strawberry roots. Rotation crops such as broccoli (+ tarping) and sweet corn reduced needle and root lesion nematodes, but that alfalfa and an oats/clover rotation increased needle nematodes. Organic blueberries tended to have more mycorrhizae but also more anthracnose fruit rot than conventional blueberries. Soil microbial counts differed substantially as a result of different organic soil amendments and mulches in the trial. As a result of our research, growers are using more environmentally friendly fungicides and disease control approaches. One grower saved $100,000 in fungicides as a result of our scouting demonstration study. Studies on the environmental requirements for infection formed the basis for a disease-forecasting model that is anticipated to result in a reduction in fungicide applications and improved disease control. As prices of certain fungicides increased, our efficacy data helped growers select choose other cost-effective alternatives. Results from this project are expected to have environmental, worker, and consumer benefits by reducing chemical use in fruit production. The project will also help maintain short-term and long-term viability of small fruit production in the United States.

Publications

  • Schilder, A. 2009. 2009 Fungicide update for blueberry. Blueberry IPM Newsletter (http://www.isaacslab.ent.msu.edu/blueberryscoutarchive.htm) 3 (1): 5-6.
  • Schilder, A., and Miles, T. 2009. Disease management: mummy berry. Blueberry IPM Newsletter (http://www.isaacslab.ent.msu.edu/blueberryscoutarchive.htm) 3 (2): 5-6.
  • Schilder, A., and Miles, T. 2009. Disease management: Mummy berry: shoot strikes. Blueberry IPM Newsletter (http://www.isaacslab.ent.msu.edu/blueberryscoutarchive.htm) 3 (5): 4-5.
  • Schilder, A., and Miles, T. 2009. Disease management: Mummy berry. Blueberry IPM Newsletter (http://www.isaacslab.ent.msu.edu/blueberryscoutarchive.htm) 3 (6): 4-5.
  • Schilder, A. 2009. Fungicide supply tightening. Blueberry IPM Newsletter (http://www.isaacslab.ent.msu.edu/blueberryscoutarchive.htm) 3 (6): 6.
  • Schilder, A. 2009. Omega 500F fungicide labeled for blueberry. Blueberry IPM Newsletter (http://www.isaacslab.ent.msu.edu/blueberryscoutarchive.htm) 3 (6): 6.
  • Schilder, A., and Miles, T. 2009. Disease management: mummy berry: shoot and flower strikes. Blueberry IPM Newsletter (http://www.isaacslab.ent.msu.edu/blueberryscoutarchive.htm) 3 (7): 5-6.
  • Schilder, A., and Miles, T. 2009. Disease management: mummy berry and blueberry shoestring virus. Blueberry IPM Newsletter (http://www.isaacslab.ent.msu.edu/blueberryscoutarchive.htm) 3 (8): 3-5.
  • Schilder, A. 2009. If blueberries are still in bloom, keep up mummy berry sprays. Blueberry IPM Newsletter (http://www.isaacslab.ent.msu.edu/blueberryscoutarchive.htm) 3 (8): 5.
  • Schilder, A. 2009. Bloom and early fruit development: a good time to control fruit rots in blueberries. Blueberry IPM Newsletter (http://www.isaacslab.ent.msu.edu/blueberryscoutarchive.htm) 3 (8): 6-7.
  • Schilder, A., and Miles, T. 2009. Disease management: mummy berry and twig blights. Blueberry IPM Newsletter (http://www.isaacslab.ent.msu.edu/blueberryscoutarchive.htm) 3 (9): 5-6.
  • Schilder, A. 2009. Michigan virus survey. Blueberry IPM Newsletter (http://www.isaacslab.ent.msu.edu/blueberryscoutarchive.htm) 3 (9): 7.
  • Schilder, A. 2009. Blossom and twig blight in blueberry. Blueberry IPM Newsletter (http://www.isaacslab.ent.msu.edu/blueberryscoutarchive.htm) 3 (9): 8.
  • Schilder, A. and Miles, T. 2009. Disease management: twig blight and mummy berry. Blueberry IPM Newsletter (http://www.isaacslab.ent.msu.edu/blueberryscoutarchive.htm) 3 (10): 4-5.
  • Schilder, A. and Miles, T. 2009. Blueberry virus survey: send your samples in to MSU for free virus testing. Blueberry IPM Newsletter (http://www.isaacslab.ent.msu.edu/blueberryscoutarchive.htm) 3 (10): 6.
  • Schilder, A. and Miles, T. 2009. Disease management: blossom blights and mummy berry fruit infection. Blueberry IPM Newsletter (http://www.isaacslab.ent.msu.edu/blueberryscoutarchive.htm) 3 (11): 6-7.
  • Schilder, A. and Miles, T. 2009. Disease management: mummy berry and mosaic. Blueberry IPM Newsletter (http://www.isaacslab.ent.msu.edu/blueberryscoutarchive.htm) 3 (12): 3-4.
  • Schilder, A. and Miles, T. 2009. Disease management: blighted twigs and mummy berry. Blueberry IPM Newsletter (http://www.isaacslab.ent.msu.edu/blueberryscoutarchive.htm) 3 (13): 3-5.
  • Schilder, A. and Miles, T. 2009. Disease management: mummy berry. Blueberry IPM Newsletter (http://www.isaacslab.ent.msu.edu/blueberryscoutarchive.htm) 3 (14): 6-8.
  • Schilder, A. and Miles, T. 2009. How to recognize symptoms of blueberry shock and scorch, two new virus diseases found in Michigan. Blueberry IPM Newsletter (http://www.isaacslab.ent.msu.edu/blueberryscoutarchive.htm) 3 (14): 8-9.
  • Schilder, A. and Miles, T. 2009. Disease management: fruit rots. Blueberry IPM Newsletter (http://www.isaacslab.ent.msu.edu/blueberryscoutarchive.htm) 3 (15): 5-6.
  • Schilder, A. and Miles, T. 2009. Disease management: anthracnose and Alternaria fruit rot. Blueberry IPM Newsletter (http://www.isaacslab.ent.msu.edu/blueberryscoutarchive.htm) 3 (16): 3-4.
  • Schilder, A. and Miles, T. 2009. Disease management. Blueberry IPM Newsletter (http://www.isaacslab.ent.msu.edu/blueberryscoutarchive.htm) 3 (17): 5-6.
  • Schilder, A. and Miles, T. 2009. Disease management. Blueberry IPM Newsletter (http://www.isaacslab.ent.msu.edu/blueberryscoutarchive.htm) 3 (18): 4-5.
  • Schilder, A. and Miles, T. 2009. Disease management: anthracnose infections throughout this season. Blueberry IPM Newsletter (http://www.isaacslab.ent.msu.edu/blueberryscoutarchive.htm) 3 (19): 4-5.
  • Schilder, A. and Miles, T. 2009. Blueberry virus update meeting. Blueberry IPM Newsletter (http://www.isaacslab.ent.msu.edu/blueberryscoutarchive.htm) 3 (20): 2.
  • Schilder, A. and Miles, T. 2009. Disease management: season overview. Blueberry IPM Newsletter (http://www.isaacslab.ent.msu.edu/blueberryscoutarchive.htm) 3 (20): 3-5.
  • Miles, T. D., and Schilder, A. M. C. 2009. First report of grape root caused by Roesleria subterranea in Michigan. Plant Disease 93: 765.
  • Wise, J. C., Jenkins, P. E., Schilder, A. M. C., Vandervoort, C., and Isaacs, R. 2009. Sprayer type and water volume influence pesticide deposition of grape clusters and control of grape berry moth and fungal diseases. Crop Protection (in press).
  • Wise, J., Zandstra, B., Miyazaki, S., and Schilder, A. 2009. Speciality (minor-use) crop pesticide prioritization in the 2009 Ir-4 Food Use Workshop. Fruit Crop Advisory Team Alert Newsletter (http://ipmnews.msu.edu/fruit/). Posted September 22, 2009.
  • Schilder, A. 2009. Late-season control of powdery mildew in grapes: eradicative treatments. Fruit Crop Advisory Team Alert Newsletter (http://ipmnews.msu.edu/fruit/). Posted September 8, 2009.
  • Schilder, A. 2009. Keep monitoring for powdery mildew in grapes. Fruit Crop Advisory Team Alert Newsletter (http://ipmnews.msu.edu/fruit/). Posted August 25, 2009.
  • Wise, J. C., Gut, L. J., Isaacs, R., Schilder, A. M. C., Sundin, G. W., Zandstra, B., Hanson, E., and Shane, B. 2009. Michigan Fruit Management Guide 2010. Extension Bulletin E-154. Michigan State University, East Lansing, MI.
  • Miles. T. D., and Schilder, A. C. 2009. Correlation of signs and symptoms of mummy berry in highbush blueberry Acta Horticulturae 810: 379-384.
  • Schilder, A. 2009. Overview of blueberry diseases during the 2009 season. Fruit Crop Advisory Team Alert Newsletter (http://ipmnews.msu.edu/fruit/). Posted September 22, 2009.
  • Schilder, A. 2009. Management of Botrytis gray mold in fall raspberries. Fruit Crop Advisory Team Alert Newsletter (http://ipmnews.msu.edu/fruit/). Posted August 25, 2009.
  • Schilder, A. 2009. Fall rains bring bunch rot pains. Fruit Crop Advisory Team Alert Newsletter (http://ipmnews.msu.edu/fruit/). Posted August 25, 2009.
  • Schilder, A. 2009. Blueberry plant virus eradication update. Fruit Crop Advisory Team Alert Newsletter (http://ipmnews.msu.edu/fruit/). Posted August 11, 2009.
  • Schilder, A. 2009. Exotic blueberry viruses found in Michigan. Fruit Crop Advisory Team Alert Newsletter (http://ipmnews.msu.edu/fruit/). Posted July 14, 2009.
  • Schilder, A. 2009. How to recognize symptoms of blueberry shock and scorch: two new viruses found in Michigan. Fruit Crop Advisory Team Alert Newsletter (http://ipmnews.msu.edu/fruit/). Posted July 14, 2009
  • Schilder, A. 2009. Focus on powdery mildew control in wine and juice grapes. Fruit Crop Advisory Team Alert Newsletter (http://ipmnews.msu.edu/fruit/). Posted July 7, 2009.
  • Schilder, A. 2009. Disease control in grapes critical during and after bloom. Fruit Crop Advisory Team Alert Newsletter (http://ipmnews.msu.edu/fruit/). Posted June 23, 2009.
  • Schilder, A. 2009. Mettle 125 ME: A new fungicide for grapes. Fruit Crop Advisory Team Alert Newsletter (http://ipmnews.msu.edu/fruit/). Posted June 9, 2009.
  • Schilder, A. 2009. Downy mildew gets an early start in grapes. Fruit Crop Advisory Team Alert Newsletter (http://ipmnews.msu.edu/fruit/). Posted June 9, 2009.
  • Schilder, A. 2009. Leather rot a threat to strawberries during cool, wet conditions. Fruit Crop Advisory Team Alert Newsletter (http://ipmnews.msu.edu/fruit/). Posted June 9, 2009.
  • Schilder, A., and Miles. T. 2009. If blueberries are still in bloom, keep up mummy berry sprays Fruit Crop Advisory Team Alert Newsletter (http://ipmnews.msu.edu/fruit/). Posted June 2, 2009.
  • Schilder, A. 2009. Bloom and early fruit development: A good time to control fruit rots in blueberries. Fruit Crop Advisory Team Alert Newsletter (http://ipmnews.msu.edu/fruit/). Posted June 2, 2009.
  • Schilder, A. 2009. Omega 500 F fungicide labeled for blueberries. Fruit Crop Advisory Team Alert Newsletter (http://ipmnews.msu.edu/fruit/). Posted May 12, 2009.
  • Schilder, A. 2009. Cool, wet weather conducive to angular leaf spot of strawberries. Fruit Crop Advisory Team Alert Newsletter (http://ipmnews.msu.edu/fruit/). Posted June 2, 2009.
  • Schilder, A. 2009. Alternatives to EBDC fungicides in grapes. Fruit Crop Advisory Team Alert Newsletter (http://ipmnews.msu.edu/fruit/). Posted May 12, 2009.
  • Schilder, A. 2009. Disease management: virus survey planned in Michigan blueberry fields in 2009. Blueberry IPM Newsletter (http://www.isaacslab.ent.msu.edu/blueberryscoutarchive.htm) 3 (2): 7.
  • Schilder, A., and Miles, T. 2009. Blueberry disease scouting protocols. Blueberry IPM Newsletter (http://www.isaacslab.ent.msu.edu/blueberryscoutarchive.htm) 3 (2): 9.
  • Schilder, A., and Miles, T. 2009. Disease management: Mummy berry: apothecia are everywhere. Blueberry IPM Newsletter (http://www.isaacslab.ent.msu.edu/blueberryscoutarchive.htm) 3 (3): 4-6.
  • Schilder, A., and Miles, T. 2009. Time to scout for mummy berry in blueberry fields. Fruit Crop Advisory Team Alert Newsletter (http://ipmnews.msu.edu/fruit/). Posted April 28, 2009.
  • Schilder, A. 2009. Fungicide update for berries and grapes. Fruit Crop Advisory Team Alert Newsletter (http://ipmnews.msu.edu/fruit/). Posted March 31, 2009.
  • Schilder, A., and Miles, T. 2009. Disease management: Mummy berry. Blueberry IPM Newsletter (http://www.isaacslab.ent.msu.edu/blueberryscoutarchive.htm) 3 (4): 3-4.
  • Schilder, A. 2009. Virus survey planned in Michigan blueberry fields in 2009. Fruit Crop Advisory Team Alert Newsletter (http://ipmnews.msu.edu/fruit/). Posted March 31, 2009.


Progress 01/01/08 to 12/31/08

Outputs
OUTPUTS: In blueberries, we identified two new diseases in 2008: Cylindrocladium spot/blight and Pseudomonas blight. We continued to evaluate scouting methods in mummy berry for the second year as part of a larger project aimed at demonstrating the benefits of scouting for management of insects and diseases in highbush blueberries. In this study, four field sites in SW Michigan (cvs. Rubel, Jersey, and Blueray) were evaluated weekly from April through August 2008. The number of overwintered pseudosclerotia, pseudosclerotia with apothecia, number of apothecia, number of blighted shoots, and the number of infected berries were enumerated. At all sites the number of apothecia had the strongest correlation with disease symptoms. A study with videocameras placed on shoot strikes in the field showed that flies may play an important role in spore dispersal. We continued our studies on the temperature-leaf wetness requirements for Colletotrichum acutatum infection on Jersey blueberries (potted plants, detached twigs, and detached fruit). The minimum wetness duration required for infection was 12 hours at 20 and 25 degrees C, 18 hours at 15 degrees C, and 36 hours at 10 degrees C. The optimal temperature for infection was 25 degrees C. Frost-guided sprays were numerically but not significantly better than calendar-style sprays with regards to mummy berry shoot strikes, but only one frost event occurred. Field studies of regular and biofungicides against mummy berry showed very good control by Serenade +Nufilm (a surfactant), even under high disease pressure. In grapes, dormant sprays of Cuprofix significantly reduced black rot. Fungicide efficacy trials showed that Stylet Oil, Sulforix, and Kaligreen were among the most effective fungicides in eradicating powdery mildew. Numerous organic fungicides were tested against black rot, Phomopsis, and downy mildew: the most effective were Serenade + NuFilm and Sonata + Nufilm. On-farm demonstration trials showed that ProPhyt performed well against downy mildew and Phomopsis. ProPhyt performance was intermediate between Ridomil and Ziram. A trial assessing performance of biological control agents, leaf removal and fungicide against sour rot and other bunch rots in grapes, showed that leaf removal overall was a good strategy to control bunch rots. A study of raspberries in tunnels showed that there were few diseases in tunnels compared to raspberries grown outside; however some powdery mildew and cane Botrytis were noted (the latter particularly at the edges where water splash could have landed on the canes). In strawberries, trials were conducted to study if fungicides and nutritional amendments could ameliorate black root rot symptoms in declining fields. Abound (drench) + ProPhyt (spray) and Abound (drench) appeared most promising in reducing root necrosis and increasing yield and plant growth. Yield increases of 70% over the untreated control were realized in the best treatments. An organic blueberry trial was established with cover crops, various nutritional amendments and mulch types. Disease pressure and soil microbial characteristics (including mycorrhizae) will be assessed over the next five years. PARTICIPANTS: In this project, we are collaborating closely in terms of research and extension activities with James Hancock (Small fruit breeder, Dept. Horticulture), Eric Hanson (Horticulturist, Dept. Horticulture), Tom Zabadal (Viticulturist, Dept. Horticulture), Rufus Isaacs (small fruit Entomologist, Dept. Entomology), John Wise (Fruit Entomologist, Dept. Entomology), Jeff Andresen (Agrometeorologist, Dept. Geography), Matt Grieshop (Organic Pest Management Specialist, Dept. Entomology), Paul Jenkins (Grape and Blueberry Education Coordinator, Dept Entomology), Stuart Grandy (Soil Biologist, Dept. Horticulture), Mark Longstroth (MSU Extension, SW Michigan), Bob Tritten (MSU Extension, Eastern Michigan), Carlos Garcia-Salazar (West-Central Michigan).The main research participants in this project were Jerri Gillett (Research Assistant), Roger Sysak (Research Technician), and Timothy Miles (PhD student) who conducted the field and laboratory research activities with assistance from undergraduate students. Experiments are conducted in fields of numerous small fruit growers in Michigan and in collaboration with personnel at the Trevor Nichols Research Complex in Fennville, MI, at the Clarksville Horticultural Experiment Station in Clarksville, MI, at the Southwest Michigan Research and Extension Center in Benton Harbor, MI, and at the Northwest Michigan Horticulture Research and Extension Station in Traverse City, MI, the MSU Horticulture Farm and MSU Plant Pathology Farm in East Lansing, MI. The project provides training opportunities to various MS and PhD students as well as undergraduate students. Partner organizations are the Michigan Blueberry Growers Association, Michigan State Horticultural Society, North American Strawberry Growers, National Grape Cooperative, Michigan Grape and Wine Industry Council, and independent berry growers. TARGET AUDIENCES: The primary target audience for the project is small fruit growers in Michigan and other Midwest states as well as extension personnel and private consultants. PROJECT MODIFICATIONS: Nothing significant to report during this reporting period.

Impacts
A better understanding of the identity and biology of small fruit pathogens is helping growers use the most appropriate fungicides and optimize fungicide timing for disease control. Data on the effects of diseases on plant growth, fruit yield and quality aid growers in making control decisions. Studies on the environmental requirements for infection are forming the basis for disease-forecasting models that will use weather data to predict infection periods. This is anticipated to result in a reduction in fungicide applications and improved disease control. Efficacy testing of reduced-risk fungicides, biological control products, natural products, and inorganic substances will lead to a diversification of disease control options and reduce the dependency of blueberry growers on conventional pesticides, especially those considered 'at risk'. Identification of sources of host plant resistance and resistance mechanisms will facilitate small fruit breeding efforts to develop resistant cultivars, and will help growers adjust their management strategies to the innate resistance in their cultivars. An understanding of the effects of commonly used pesticides on non-target organisms, and of cultural practices on disease severity, will help growers choose management practices that are ecologically and biologically sound. Results from this project are expected to have environmental, worker, and consumer benefits by reducing chemical use in fruit production. The project will also help maintain short-term and long-term viability of small fruit production in the United States.

Publications

  • Miles, T., and Schilder, A. 2008. Disease update: Shoot strikes strike back! Michigan Blueberry IPM Update, Vol. 2 (5): 4.
  • Schilder, A. 2008. Topsin M Section 18 request for blueberries denied by EPA. Michigan Blueberry IPM Update, Vol. 2 (4): 5.
  • Schilder, A., Isaacs, R., Hanson, and Cline, B. 2008. A Pocket Guide to IPM Scouting in Highbush Blueberries. Michigan State University Extension Bulletin E-2928. 2nd Edition.
  • Schilder, A., Isaacs, R., Hanson, Cline, B., Garcia-Salazar, C., and France, A. 2008. A Pocket Guide to IPM Scouting in Highbush Blueberries. Michigan State University Extension Bulletin E-2928. (Spanish version).
  • Schilder, A., Wharton, P., and Miles. T. 2008. Mummy berry. Michigan State University Extension Bulletin E-2846.
  • Schilder, A., and Miles, T. 2008. Virus and Viruslike Diseases of Blueberries. Michigan State University Extension Bulletin E-3048.
  • Isaacs, R., Schilder, A., and Miles, T. 2008. Blueberry Aphid and Shoestring Virus. Michigan State University Extension Bulletin, E-3050.
  • Wise, J. C., Gut, L. J., Isaacs, R., Schilder, A. M. C., Sundin, G. W., Zandstra, B., Hanson, E., and Shane, B. 2008. Michigan Fruit Management Guide 2009. Extension Bulletin E-154. Michigan State University, East Lansing, MI.
  • Miles. T. D., and Schilder, A. M. C. 2008. Correlation of mummy berry signs and symptoms. Acta Horticulturae (in press).
  • Gillett, J. M., and Schilder, A. M. C. 2008. Environmental requirements for infection of blueberry fruit by Colletotrichum acutatum. Acta Horticulturae (in press).
  • Miles, T. D., Wharton, P. S., and Schilder, A. M. C. 2008. Cytological and chemical evidence for an active resistance response to infection by Colletotrichum acutatum in Elliott blueberries. Acta Horticulturae (in press).
  • Schilder, A. M. C., Gillett, J. M., and Sysak, R. W. 2008. Evaluation of fungicides for control of powdery mildew, downy mildew, black rot, and Phomopsis in grapes, 2007. Plant Disease Management Reports 2:SMF044.
  • Schilder, A. M. C., Gillett, J. M., and Sysak, R. W. 2008. Evaluation of fungicides for control of powdery mildew, Botrytis bunch rot, and sour rot in grapes, 2007. Plant Disease Management Reports 1:SMF043.
  • Schilder, A. M. C., Gillett, J. M., and Sysak, R. W. 2008. Evaluation of fungicides for control of foliar, cane and fruit diseases of red raspberries, 2007. Plant Disease Management Reports 1:SMF043.
  • Miles. T., and Schilder, A. 2008. Anthracnose Fruit Rot. Michigan State University Extension Bulletin, E-3039.
  • Hanson, E., Isaacs, R., and Schilder, A. 2008. Raspberries and tunnels are a great match. The Fruit Growers News Vol. 47 (4): 46-47.
  • Schilder, A. 2008. Effect of water pH on the stability of pesticides. Utah Berry Growers Association Newsletter Vol. 1: 3-6.
  • Schilder, A. 2008. Disease control after spring freeze injury. Weekly Vineyard IPM Scouting Summary. Report for Week of May 8, 2008. http://www.isaacslab.ent.msu.edu/grapescout/8may08.pdf.
  • Miles, T., and Schilder, A. 2008. Disease update: mummy berry. Michigan Blueberry IPM Update, Vol. 2 (1): 3.
  • Schilder, A. 2008. Pest of the week: mummy berry. Michigan Blueberry IPM Update, Vol. 2 (1): 5-6.
  • Schilder, A. 2008. Fungicide label update. Michigan Blueberry IPM Update, Vol. 2 (1): 8-9.
  • Miles, T., and Schilder, A. 2008. Disease update: Attack of the mummy berries! Michigan Blueberry IPM Update, Vol. 2 (2): 3.
  • Miles, T., and Schilder, A. 2008. Disease update: Mummy berry. Michigan Blueberry IPM Update, Vol. 2 (3): 4.
  • Schilder, A. 2008. Pest of the Week: Botrytis. Michigan Blueberry IPM Update, Vol. 2 (3): 2.
  • Schilder, A. 2008. Effect of water pH on stability of pesticides. Michigan Blueberry IPM Update, Vol. 2 (3): 6-8.
  • Schilder, A. 2008. Topsin M Section 18 request for blueberries still pending. Michigan Blueberry IPM Update, Vol. 2 (3): 9.
  • Miles, T., and Schilder, A. 2008. Disease update: Mummy berry presses on. Michigan Blueberry IPM Update, Vol. 2 (4): 4.
  • Miles, T., and Schilder, A. 2008. Pest of the week,anthracnose. Michigan Blueberry IPM Update, Vol. 2 (5): 2.
  • Schilder, A. 2008. Effect of water pH on the stability of pesticides. Fruit Crop Advisory Team Vol. 23 (1).
  • Schilder, A. 2008. Effect of water pH on the stability of pesticides. New York Berry News Vol. 7 (5) (online version).
  • Schilder, A. 2008. Topsin M Section 18 request for blueberries still pending. Fruit Crop Advisory Team Vol. 23 (5).
  • Schilder, A. 2008. Correction: PropiMax fungicide is not labeled for strawberries. Fruit Crop Advisory Team Vol. 23 (5).
  • Schilder, A. 2008. Disease control after spring freeze injury in grapes: Keep on top of Phomopsis. Fruit Crop Advisory Team Vol. 23 (6).
  • Miles, T., and Schilder, A. 2008. Mummy berry shoot strikes sighted in blueberries. Fruit Crop Advisory Team Vol. 23 (6).
  • Schilder, A. 2008. Topsin M Section 18 request for blueberries denied by EPA. Fruit Crop Advisory Team Vol. 23 (7).
  • Schilder, A. 2008. Fungicide label update for small fruit crops in 2008. Fruit Crop Advisory Team Vol. 23 (1).
  • Schilder, A. 2008. PropiMax fungicide labeled for use in blueberries. Fruit Crop Advisory Team Vol. 23 (2).
  • Schilder, A. 2008. Now is a good time to monitor for mummy berry in blueberries. Fruit Crop Advisory Team Vol. 23 (3).
  • Jenkins, P., Isaacs, R., and Schilder, A. 2008. Blueberry IPM kick-off meeting. Fruit Crop Advisor Team Vol. 23 (3).


Progress 01/01/07 to 12/31/07

Outputs
In blueberries, we evaluated scouting methods for mummy berry as part of a larger project aimed at demonstrating the benefits of scouting for management of insects and diseases in highbush blueberries. In this study, four field sites in southwest Michigan (cvs. Rubel, Jersey, and Blueray) were evaluated once a week from April through August 2007. The number of overwintered pseudosclerotia, pseudosclerotia with apothecia, number of apothecia, number of blighted shoots, and the number of infected berries were counted at ten locations per field. At all sites the number of apothecia had the strongest correlation with overall disease at the end of the growing season. We continued our studies to determine the temperature-leaf wetness requirements for Colletotrichum acutatum infection on Jersey blueberries (potted plants, detached twigs, and detached fruit). The minimum wetness duration required for infection was 12 hours at 20 and 25 degrees C, 18 hours at 15 degrees C, and 36 hours at 10 degrees C. The optimal temperature for infection was 25 degrees C. Frost-guided sprays were not significantly different from calendar-style sprays with regards to mummy berry shoot strikes, but disease pressure was very low. Field studies of commercial and experimental biocontrol agents against anthrcanose fruit rot showed significant control by Serenade and B109, a native bacterium isolated from blueberry fruit. In grapes, dormant sprays of Cuprofix significantly reduced Phomopsis, black rot, and downy mildew. Spring applications tended to be better than fall applications. Spray volume trials showed that both protectant and systemic fungicides tended to work better when applied with an airblast sprayer at 50 gal/acre versuys 20 gal/acre, but not always significantly so. Fungicide efficacy trials showed that Stylet Oil, Sulforix, and Kaligreen were among the most effective fungicides in eradicating powdery mildew. Cleistothecium production was reduced most by Kaligreen, Elite, Cuprofix and Sulforix. On-farm demonstration trials showed that ProPhyt performed well against downy mildew and Phomopsis. ProPhyt performance was intermediate between Ridomil and Ziram. Pathogenicity tests of Eutypella vitis on grape cuttings showed that most isolates were able to infect and discolor wood of grapevine cuttings. Eutypella vitis isolates were characterized morphologically and genetically. Spatial analysis of Eutypa dieback symptoms showed clustering in some but not all vineyards. Patterns of spread appeared to follow the prevailing wind direction. In strawberries, trials were conducted to study if fungicides and nutritional amendments could ameliorate black root rot symptoms in declining fields. Abound and Symbex drenches and ProPhyt sprays appeared most promising in reducing root necrosis and increasing yield. Yield increases of 70% were realized in the best treatments.

Impacts
A better understanding of the identity and biology of small fruit pathogens will help growers use the most appropriate fungicides and optimize fungicide timing for the diseases they are trying to control. Data on the effects of diseases on plant growth, fruit yield and quality will aid growers in making control decisions. Studies on the environmental requirements for infection are expected to form the bases of disease-forecasting models that use weather data to predict infection periods. This will hopefully result in a reduction in fungicide applications. Efficacy testing of reduced-risk fungicides, biological control products, natural products, and inorganic substances will lead to a diversification of disease control options and reduce the dependency of blueberry growers on conventional pesticides, especially those considered 'at risk'. Identification of sources of host plant resistance and resistance mechanisms will facilitate small fruit breeding efforts to develop resistant cultivars, and will help growers adjust their management strategies to the innate resistance in their cultivars. An understanding of the effects of commonly used pesticides on non-target organisms, and of cultural practices on disease severity, will help growers choose management practices that are ecologically and biologically sound. Results from this project are expected to have environmental, worker, and consumer benefits by reducing chemical use in fruit production. The project will also help maintain short-term and long-term viability of small fruit production in the United States

Publications

  • Catal, M., Jordan, S., Butterworth, S. E., and Schilder, A. M. C. 2007. A PCR-based method to distinguish Eutypa lata and Eutypella vitis from grapevine. Phytopathology 97: 737-747.
  • Wharton P.S., and Schilder, A.C., 2007. Novel infection strategies of Colletotrichum acutatum on ripe blueberry fruit. Plant Pathology Doi: 10.1111/j.1365-3059.2007.01698.x.
  • Popa, I., Hanson, E., Todd, E., Schilder, A., and Ryser, E. 2007. Efficacy of chlorine dioxide gas sachets for enhancing the microbiological quality and safety of blueberries. Journal of Food Protection 70:2084-2088.
  • Isaacs, R., Schilder, A., Zabadal, T., and Weigle. T. 2007. A pocket guide for grape IPM scouting in the North Central and Eastern U.S. Michigan State University Extension Bulletin E-2889. 3rd Edition.
  • Wise, J. C., Gut, L. J., Isaacs, R., Schilder, A. M. C., Sundin, G. W., Zandstra, B., Hanson, E., and Shane, B. 2007. Michigan Fruit Management Guide 2008. Extension Bulletin E-154. Michigan State University, East Lansing, MI.
  • Schilder, A. M. C., Gillett, J. M., and Sysak, R. W. 2007. Evaluating reduced-risk fungicides for anthracnose control in blueberries, 2006. Plant Disease Management Reports 1:SMF014.
  • Schilder, A. M. C., Gillett, J. M., and Sysak, R. W. 2007. Evaluation of reduced risk fungicides for disease control in Niagara grapes, 2006. Plant Disease Management Reports 1:SMF015.
  • Schilder, A. M. C., Gillett, J. M., and Sysak, R. W. 2007. Evaluation of fungicides for control of Botrytis bunch rot and powdery mildew in grapes, 2006. Plant Disease Management Reports 1:SMF016.
  • Schilder, A. M. C., Gillett, J. M., and Glass, B. W. 2007. Determining the pathogenicity of Rhizoctonia, Pythium, and Cylindrocarpon on raspberry roots. Phytopathology 97:S104.
  • Schilder, A. 2007. Fungicide label update for blueberries. Fruit Crop Advisory Team Vol. 22 (1): 5-6
  • Schilder, A. 2007. Monitor for mummy berry in blueberries. Fruit Crop Advisory Team Vol. 22 (5).
  • Schilder, A. 2007. Be on the look-out for Phomopsis twig blight in blueberries. Fruit Crop Advisory Team Vol. 22 (6).
  • Schilder, A. 2007. Mummy berry update in blueberries. Fruit Crop Advisory Team Vol. 22 (6).
  • Schilder, A. 2007. Blossom blight in blueberries. Fruit Crop Advisory Team Vol. 22 (7).
  • Schilder, A. 2007. Bloom is a critical time for control of Botrytis gray mold in strawberries. Fruit Crop Advisory Team Vol. 22 (7).
  • Schilder, A. 2007. Blueberry scorch, shock, and sheep Penn hill virus quarantine. Fruit Crop Advisory Team Vol. 22 (8).
  • Schilder, A. 2007. Disease control in grapes critical during and after bloom. Fruit Crop Advisory Team Vol. 22 (9).
  • Schilder, A. 2007. Get a head start on management of bunch rot diseases in grapes. Fruit Crop Advisory Team Vol. 22 (12).
  • Schilder, A. 2007. Warm humid weather is conducive to powdery mildew in grapes. Fruit Crop Advisory Team Vol. 22 (13).
  • Schilder, A. 2007. Options for late-season disease control in grape vineyards. Fruit Crop Advisory Team Vol. 22 (15).
  • Schilder, A. 2007. Fire blight on raspberries and blackberries. Fruit Crop Advisory Team Vol. 22 (15).
  • Schilder, A. 2007. Botrytis gray mold in fall raspberries. Fruit Crop Advisory Team Vol. 22 (16).
  • Schilder, A. 2007. Overview of small fruit diseases during the 2007 growing season. Fruit Crop Advisory Team Vol. 22 (18).


Progress 01/01/06 to 12/31/06

Outputs
In blueberries, studies to determine the temperature-leaf wetness requirement for Colletotrichum acutatum infection were continued on Jersey blueberries (potted plants, as well as detached twigs and detached fruit). Infection incidence increased significantly between 12 and 24 h of wetness. Spore trapping of Colletotrichum conidia showed a clear peak in May around bloom. Frost-guided spray trials, which account for increased susceptibility of blueberry shoots to mummy berry shoot strikes after a frost, were somewhat more effective than calendar-style sprays, but there was only one frost event during the susceptible period. Sulfur 6L (sulfur), Cuprofix (copper sulfate), and Sulforix (calcium polysulfide) applied as dormant sprays again reduced mummy berry shoot strike. V10116 (an experimental fungicide) continued to perform well. The phosphorous acid fungicides (ProPhyt, Phostrol, and Agri-Fos) provided moderate control of anthracnose and poor control of mummy berry. Studies of biocontrol potential of blueberry fruit microbes against blueberry fruit pathogens yielded several promising bacteria (Bacillus spp.) and yeasts. These will be further tested in planta and in the field. In grapes, dormant sprays of Sulfur 6L and Cuprofix significantly reduced Phomopsis, black rot, powdery mildew, and downy mildew. Timing of dormant sprays affected efficacy. ProPhyt and Phostrol, Citrex (ascorbic and other acids), and Prev-Am (boric acid) provided good to excellent control of downy mildew, Phomopsis, and black rot, and moderate control of powdery mildew in grapes. Field scouting demonstration trials again were successful in saving grape growers pesticide sprays. Dormant sprays and ProPhyt were also demonstrated to be effective on a farm scale. Pathogenicity tests of Eutypella vitis on grape cuttings continued and showed that most isolates were able to infect and discolor wood of grapevine cuttings. Spatial analysis of Eutypa dieback symptoms in the field is underway. In strawberries, an integrated black root rot management trial was established with a resistant and susceptible strawberry variety planted in fumigated, rotation, or non-fumigated plots with sub-treatments consisting of a non-treated area, compost socks, ProPhyt and Abound fungicides, and the biocontrol product Actinovate. The number of daughters, number of runners, plant vigor, and plant fill were all gathered from each of the treatment combinations. A raspberry trial showed good activity of Scala (pyrimethanil) against Botrytis fruit rot. Inoculations of raspberry plants with Rhizoctonia, Pythium and Cylindrocarpon spp. showed that these fungi can cause a root rot and death of above-ground plant parts. Combined infections generally resulted in more severe symptoms than individual infections. This shows that a replant disease similar to black root rot in strawberries can affect raspberries.

Impacts
A better understanding of the identity and biology of small fruit pathogens will help growers use the most appropriate fungicides and optimize fungicide timing for the diseases they are trying to control. Data on the effects of diseases on plant growth, fruit yield and quality will aid growers in making control decisions. Studies on the environmental requirements for infection are expected to form the bases of disease-forecasting models that use weather data to predict infection periods. This will hopefully result in a reduction in fungicide applications. Efficacy testing of reduced-risk fungicides, biological control products, natural products, and inorganic substances will lead to a diversification of disease control options and reduce the dependency of blueberry growers on conventional pesticides, especially those considered 'at risk'. Identification of sources of host plant resistance and resistance mechanisms will facilitate small fruit breeding efforts to develop resistant cultivars, and will help growers adjust their management strategies to the innate resistance in their cultivars. An understanding of the effects of commonly used pesticides on non-target organisms, and of cultural practices on disease severity, will help growers choose management practices that are ecologically and biologically sound. Results from this project are expected to have environmental, worker, and consumer benefits by reducing chemical use in fruit production. The project will also help maintain short-term and long-term viability of small fruit production in the United States

Publications

  • Schilder, A. 2006. BSP Sulforix label had been amended for blueberries. MSU Extension Fruit Crop Advisory Team Alert 21 (3): 3.
  • Isaacs, R., and Schilder, A. 2006. Pest management in frost-damaged vineyards. MSU Extension Fruit Crop Advisory Team Alert 21 (4): 2-5.
  • Schilder, A. 2006. Bloom is a critical time for control of Botrytis gray mold in strawberries. MSU Extension Fruit Crop Advisory Team Alert 21 (6): 7.
  • Schilder, A. 2006. Weather conditions are ideal for Phomopsis diseases. MSU Extension Fruit Crop Advisory Team Alert 21 (6): 8.
  • Schilder, A. 2006. Cool wet weather conducive to angular leaf spot of strawberries. MSU Extension Fruit Crop Advisory Team Alert 21 (7): 4.
  • Schilder, A. 2006. It is not too late for dormant sprays against Phomopsis in grapes. MSU Extension Fruit Crop Advisory Team Alert 21 (3): 2-3.
  • Schilder, A. 2006. Testing for viruses in blueberries. MSU Extension Fruit Crop Advisory Team Alert 21 (15): 2.
  • Schilder, A. 2006. Management of bunch rot diseases in grapes. MSU Extension Fruit Crop Advisory Team Alert 21 (15): 2-3.
  • Schilder, A. 2006. Botrytis gray mold control in fall raspberries. MSU Extension Fruit Crop Advisory Team Alert 21 (17): 3.
  • Wise, J.C., Gut, L.J., Isaacs, R., Schilder, A.M.C., Zandstra, B., Hanson, E., and Shane, B. 2006. Michigan Fruit Management Guide 2007. Extension Bulletin E-154. Michigan State University, East Lansing, MI.
  • Schilder, A. M. C., and Wharton, P. S., 2006. The infection process of Colletotrichum acutatum on blueberries. Acta Horticulturae 751: 513-518.
  • Schilder, A. M. C., Hancock, J. F., Hanson, E. J. 2006. An integrated approach to disease control in blueberries in Michigan. Acta Horticulturae 751: 481-488.
  • Schilder, A. M. C., Lehman, B. L., Jordan, S. A., and Catal, M. 2006. Pathogenic and genetic variation among Plasmopara viticola isolates from different hosts. Pages 93-94 in: Proceedings of the 5th international Workshop on Grapevine Downy and Powdery Mildew. I. Pertot, C. Gessler, D. Gadoury, W. Gubler, H.-H. Kassemeyer, and P. Magarey, eds. 196 pp.
  • Schilder, A. M. C., Lehman, B. L., and Flore, J. A. 2006. Effects of downy mildew on photosynthetic parameters in Niagara grape leaves. Pages 52-53 in: Proceedings of the 5th international Workshop on Grapevine Downy and Powdery Mildew. I. Pertot, C. Gessler, D. Gadoury, W. Gubler, H.-H. Kassemeyer, and P. Magarey, eds. 196 pp.
  • Schilder, A.M.C., Gillett, J.M., and Sysak, R.W. 2006. Evaluation of fungicides for control of mummy berry in Rubel blueberries, 2005. Fungicide and Nematicide Tests 61:SMF023.
  • Schilder, A.M.C., Gillett, J.M., and Sysak, R.W. 2006. Evaluation of fungicides for control of anthracnose fruit rot in Jersey blueberries, 2005. Fungicide and Nematicide Tests 61:SMF025.
  • Schilder, A.M.C., Gillett, J.M., and Sysak, R.W. 2006. Evaluation of fungicides and dormant sprays for control of mummy berry in blueberries, 2005. Fungicide and Nematicide Tests 61:SMF024.
  • Schilder, A.M.C., Gillett, J.M., and Sysak, R.W. 2006. Evaluation of fungicides for control of anthracnose fruit rot in Rubel blueberries, 2005. Fungicide and Nematicide Tests 61:SMF026.
  • Schilder, A.M.C., Gillett, J.M., and Sysak, R.W. 2006. Evaluation of dormant and seasonal fungicide applications for disease control in Niagara grapes, 2005. Fungicide and Nematicide Tests 61:SMF027.
  • Schilder, A.M.C., Gillett, J.M., and Sysak, R.W. 2006. Evaluation of fungicides for control of Phomopsis and powdery mildew in wine grapes, 2005. Fungicide and Nematicide Tests 61:SMF028.
  • Schilder, A.M.C., Gillett, J.M., and Sysak, R.W. 2006. Evaluation of fungicides for control of black rot and powdery mildew in Concord grapes, 2005. Fungicide and Nematicide Tests 61:SMF029.
  • Schilder, A.M.C., Gillett, J.M., and Sysak, R.W. 2006. Evaluation of fungicides for control of anthracnose in Concord grapes, 2005. Fungicide and Nematicide Tests 61:SMF030.
  • Schilder, A.M.C., Gillett, J.M., and Sysak, R.W. 2006. Evaluation of fungicides and spray timing for control of Phomopsis in Niagara grapes, 2005. Fungicide and Nematicide Tests 61:SMF031.
  • Schilder, A.M.C., Gillett, J.M., and Sysak, R.W. 2006. Evaluation of fungicides for control of diseases in red raspberries, 2005. Fungicide and Nematicide Tests 61:SMF032.
  • Schilder, A. 2006. Are dormant sprays useful for control of disease management in blueberries? Michigan Blueberry Advisory Committee BluesNews 1: 7.
  • Schilder, A. 2006. What fungicide do I choose for disease control in strawberries? New York Berry Times 5 (5): 12-14. http://www.nysaes.cornell.edu/pp/extension/tfabp/newslett/nybn55b.pdf .
  • Schilder, A. 2006. Blueberries receive Section 18 for Indar and Topsin M for 2006 season. MSU Extension Fruit Crop Advisory Team Alert 21 (1): 5-6.
  • Schilder, A. 2006. Bloom is a good time to start control of fruit rots in blueberries. MSU Extension Fruit Crop Advisory Team Alert 21 (7): 4-5.
  • Schilder, A. 2006. Monitor for orange rust in brambles. MSU Extension Fruit Crop Advisory Team Alert 21 (8): 3-4.
  • Schilder, A. 2006. Disease control in grapes during and after bloom. MSU Extension Fruit Crop Advisory Team Alert 21 (10): 3-5.
  • Schilder, A. 2006. Control of post-harvest fruit rots in blueberries. MSU Extension Fruit Crop Advisory Team Alert 21 (13): 3.
  • Schilder, A. 2006. Grape disease update. MSU Extension Fruit Crop Advisory Team Alert 21 (13): 3-4.


Progress 01/01/05 to 12/31/05

Outputs
In blueberries, the effect of frost (-0.5, -1.0, -1.5, -2.0 degreesC) on mummy berry shoot strike susceptibility was studied in young shoots of Bluehaven blueberry plants. Susceptibility increased with decreasing temperature. In fact, no infections occurred without frost. The temperature-leaf wetness requirement for Colletotrichum acutatum infection of fruit was studied in Jersey blueberries (potted plants, as well as detached twigs and detached fruit). In general, infection incidence increased significantly between 12 and 24 h of wetness, suggesting that the critical wetness period is >12 hours. Infection increased further at 36 and 48 hours of wetness. Infection was optimal at 20 and 25 degreesC and was less at 15 degrees and 30 degrees C. Fungicide efficacy trials against mummy berry and anthracnose showed that Sulfur 6L (sulfur), Cuprofix (copper sulfate), and Sulforix (lime sulfur) as dormant sprays significantly reduced mummy berry shoot strike as well as anthracnose. Among the new and experimental fungicides for mummy berry control, V10116 was the only one that was equal to or better than Indar. Pristine showed better activity against mummy berry fruit infection than shoot strike infection. Season-long sulfur sprays reduced anthracnose significantly, but some phytotoxicity was noted. Evaluation of enzyme production by blueberry fruit surface microbes showed that most yeasts, fungi, and bacteria produced amylase, and some pectinase and cellulase. Amylase production has been shown to reduce baking quality of products made with blueberries. A protocol for reducing microbial contamination of harvested blueberries was developed in coordination with a horticulturist and food microbiologist. In grapes, dormant sprays of Sulfur 6L and Cuprofix significantly reduced Phomopsis and black rot, and powdery mildew at harvest. Dormant sprays of Sulfur 6L significantly reduced Phomopsis spore release as well. Field scouting demonstration trials were successful in that most growers saved 1-2 fungicide and insecticide sprays per season. Specific PCR primers developed for Eutypa lata and Eutypella vitis, two fungi found on grapes with Eutypa dieback in Michigan, worked well in a field testing protocol. Both fungi were detected in wood samples in the same vineyard and sometimes within the same vine. Pathogenicity tests of Eutypella vitis showed that most isolates were able to infect and discolor wood of grapevine cuttings. Foliar symptoms were not correlated with lesion length but were generally milder than those caused by an E. lata isolate from California, but similar to Michigan E. lata isolates. In strawberries, field tests of transplant root dips and drenches with fungicides and biocontrol agents showed that fungicide drenches (Abound [azoxystrobin] and ProPhyt [phosphorous acid] improved vegetative growth almost as much as methyl bromide fumigation. DiTera (Myrothecium verrucaria), a biological nematicide also worked well. Fungicide trials for control of foliar and fruit diseases showed that phosphorous acid fungicides worked well for leather rot control.

Impacts
A better understanding of the identity and biology of small fruit pathogens will help growers use the most appropriate fungicides and optimize fungicide timing for the diseases they are trying to control. Data on the effects of diseases on plant growth, fruit yield and quality will aid growers in making control decisions. Studies on the environmental requirements for infection are expected to form the bases of disease-forecasting models that use weather data to predict infection periods. This will hopefully result in a reduction in fungicide applications. Efficacy testing of reduced-risk fungicides, biological control products, natural products, and inorganic substances will lead to a diversification of disease control options and reduce the dependency of blueberry growers on conventional pesticides, especially those considered 'at risk'. Identification of sources of host plant resistance and resistance mechanisms will facilitate small fruit breeding efforts to develop resistant cultivars, and will help growers adjust their management strategies to the innate resistance in their cultivars. An understanding of the effects of commonly used pesticides on non-target organisms, and of cultural practices on disease severity, will help growers choose management practices that are ecologically and biologically sound. Results from this project are expected to have environmental, worker, and consumer benefits by reducing chemical use in fruit production. The project will also help maintain short-term and long-term viability of small fruit production in the United States.

Publications

  • Wise, J.C., Gut, L.J., Isaacs, R., Schilder, A.M.C., Zandstra, B., Hanson, E., and Shane, B. 2004. Michigan Fruit Management Guide 2005. Extension Bulletin E-154. Michigan State University, East Lansing, MI. 183 pp.
  • Cline, B., and Schilder, A. M. C. 2005. Identification and control of blueberry diseases, Chapter 5 (16 pp.) in: Blueberry Production, N. Childers and P. Lyrene, eds.
  • Wharton, P. S., and Schilder, A. M. C. 2005. Effect of temperature on apothecial longevity and ascospore discharge by apothecia of Monilinia vaccinii-corymbosi. Plant Disease 89: 397-403.
  • Schilder, A.M.C., Erincik, O., Castlebury, L., Rossman, A., and Ellis, M. 2005. Characterization of Phomopsis spp. infecting grapes in the Great Lakes Region of North America. Plant Disease 89:755-762.
  • Hanson, E., Berkheimer, S., Schilder, A., Isaacs, R., and Kravchenko. A. 2005. Raspberry variety performance in southern Michigan. HortTechnology 15:716-721.
  • Schilder, A. M. C., Smokevitch, S. M., Catal, M., and Mann, W. K. 2005. First report of anthracnose caused by Elsinoe ampelina on grapes in Michigan. Plant Disease 89: 1011.
  • Schilder, A.M.C., Gillett, J.M., and Sysak, R.W. 2005. Evaluation of fungicides for control of mummy berry in blueberries, 2004. Fungicide and Nematicide Tests 60:SMF013.
  • Schilder, A.M.C., Gillett, J.M., and Sysak, R.W. 2005. Evaluation of fungicides for control of anthracnose fruit rot in blueberries, 2004. Fungicide and Nematicide Tests 60:SMF014.
  • Schilder, A.M.C., Gillett, J.M., and Sysak, R.W. 2005. Evaluation of fungicides for control of mummy berry in blueberries, 2004. Fungicide and Nematicide Tests 60:SMF015.
  • Schilder, A.M.C., Gillett, J.M., and Sysak, R.W. 2005. Evaluation of fungicides for control of anthracnose fruit rot in blueberries, 2004. Fungicide and Nematicide Tests 60:SMF016.
  • Schilder, A.M.C., Gillett, J.M., and Sysak, R.W. 2005. Evaluation of fungicides for control of powdery mildew and Phomopsis in grapes, 2004. Fungicide and Nematicide Tests 60:SMF017.
  • Schilder, A.M.C., Gillett, J.M., and Sysak, R.W. 2005. Evaluation of fungicides for control of foliar diseases and black rot in grapes, 2004. Fungicide and Nematicide Tests 60:SMF018.
  • Schilder, A.M.C., Gillett, J.M., and Sysak, R.W. 2005. Evaluation of fungicides for control of Botrytis bunch rot and other fruit diseases in grapes, 2004. Fungicide and Nematicide Tests 60:SMF019.
  • Schilder, A. 2005. Reducing disease pressure in grapes with dormant fungicide applications. Fruit Crop Advisory Team Alert 20 (2): 3-5.
  • Schilder, A. 2005. 2005 Label update for blueberries. Fruit Crop Advisory Team Alert 20 (2): 5-6.
  • Schilder, A. 2005. Cane anthracnose found in some blueberry fields. Fruit Crop Advisory Team Alert 20 (3): 5-6.
  • Schilder, A. 2005. Section 18 for Topsin M granted for blueberries. Fruit Crop Advisory Team Alert 20 (4): 4.
  • Schilder, A. 2005. Control of Phomopsis twig blight and canker in blueberries. Fruit Crop Advisory Team Alert 20 (4): 4-5.
  • Schilder, A. 2005. Options for control of fruit rots in blueberries. Fruit Crop Advisory Team Alert 20 (4): 5-6.
  • Schilder, A. 2005. Phosphorous acid fungicides. Fruit Crop Advisory Team Alert 20 (5): 2-3.
  • Schilder, A. 2005. Gray mold gains foothold in strawberries at bloom. Fruit Crop Advisory Team Alert 20 (6): 5.
  • Isaacs, R., and Schilder, A. 2005. Invitation to participate in Vineyard IPM Scouting Project. Fruit Crop Advisory Team Alert 20 (6): 6.
  • Schilder, A. 2005. Blueberry and grape disease update. Fruit Crop Advisory Team Alert 20 (7): 5-6.
  • Schilder, A. 2005. Disease control in grapes during and after bloom. Fruit Crop Advisory Team Alert 20 (8): 3-5.
  • Schilder, A. 2005. Orange rust, a colorful nemesis of brambles. Fruit Crop Advisory Team Alert 20 (9): 4-5.
  • Schilder, A. 2005. Cane anthracnose found in some blueberry fields. New York Berry Times 4 (6): 8. http://www.nysaes.cornell.edu/pp/extension/tfabp/newslett.shtml.
  • Schilder, A. 2005. Blueberry freeze injury or Phomopsis? New York Berry Times 4 (1): 3. http://www.nysaes.cornell.edu/pp/extension/tfabp/newslett.shtml.
  • Schilder, A., and Grube, B. 2005. Monitoring and control of mummy berry in blueberries. Fact Sheet, University of New Hampshire Cooperative Extension.
  • Isaacs, R., VanTimmeren, S., and Schilder, A., Grape IPM Project. Grape Society Newsletter, May 2005.
  • Schilder, A., and Van Timmeren, S. 2005. Slimy things in the vineyard. Fruit Crop Advisory Team Alert 20 (9): 5-6.
  • Schilder, A. 2005. When it rains, it spores, watch out for grape diseases. Fruit Crop Advisory Team Alert 20 (10): 3-4.
  • Schilder, A. 2005. Control of fruit rots in blueberries after bloom. Fruit Crop Advisory Team Alert 20 (10): 4-5.
  • Schilder, A. 2005. Can pathogens tell the difference between dew and rain? Fruit Crop Advisory Team Alert 20 (11): 3-4.
  • Schilder, A. 2005. Is there a need to apply fungicides during dry spells? Fruit Crop Advisory Team Alert 20 (12): 5.
  • Schilder, A., and Sundin, G. 2005. Post-harvest treatments available for stone fruit. Fruit Crop Advisory Team Alert 20 (13): 1.
  • Schilder, A. 2005. Prevention of pre- and post-harvest fruit rots in blueberries. Fruit Crop Advisory Team Alert 20 (13): 1-2.
  • Schilder, A. 2005. Downy mildew of grapes: things to consider. Fruit Crop Advisory Team Alert 20 (13): 2-3.
  • Schilder, A., and Sundin, G. 2005. Alternaria fruit rot in cherries and blueberries. Fruit Crop Advisory Team Alert 20 (13): 3.
  • Schilder, A. 2005. Grape disease update. Fruit Crop Advisory Team Alert 20 (14): 6-7.
  • Schilder, A. 2005. Controlling Botrytis bunch rot in grapes. Fruit Crop Advisory Team Alert 20 (15): 5-6.
  • Schilder, A. 2005. New blackberry rust invading the United States. Fruit Crop Advisory Team Alert 20 (15): 6-7.
  • Schilder, A. 2005. Fire blight on raspberries and blackberries. Fruit Crop Advisory Team Alert 20 (16): 4-5.
  • Schilder, A. 2005. Control of Phomopsis twig blight and canker in blueberries. Fruit Crop Advisory Team Alert 20 (17): 5-6.
  • Schilder, A. 2005. Small fruit diseases during the 2005 growing season. Fruit Crop Advisory Team Alert 20 (18): 1-3.
  • Schilder, A. 2005. Blueberry website developed. Fruit Crop Advisory Team Alert 20 (18): 3.
  • Wise, J., Schilder, A., Zandstra, B., and Miyazaki, S. 2005. Minor-use crop pesticide prioritization in the 2005 IR-4 Food Use Workshop. Fruit Crop Advisory Team Alert 20 (18): 3-4.
  • Schilder, A. 2005. Prevention of pre- and post-harvest fruit rots in blueberries. New York Berry Times 4 (7): 11-12. http://www.nysaes.cornell.edu/pp/extension/tfabp/newslett.shtml.


Progress 01/01/04 to 12/31/04

Outputs
In blueberries, Monilinia vaccinii ascospores were trapped in blueberry fields during the spring for three years. Spore catches displayed a diurnal pattern, with peak spore dispersal generally occurring in the evening. Numbers were higher in 2002 than 2003 or 2004, reflecting disease ratings in the same fields. Fungicide efficacy trials showed that Indar, V11016, and a Bravo/Topsin M program were most effective against mummy berry, but disease pressure was low to moderate. Mummies left in the field and collected in December germinated, but not make apothecia when collected in December, whereas mummies collected later in the winter were able to fully germinate. Experiments to study the environmental requirements for infection of green and ripe berries by Colletotrichum acutatum showed that there was a significant increase in infection at 24 h vs. 12 h of wetness. Characterization of microbial populations on blueberry fruit surfaces of green and ripe fruit showed a peak in yeast, fungal, and bacterial populations at the second harvest. C. acutatum was particularly prevalent. A test with a biofumigant fungus (Muscodor albus) showed a reduction in post-harvest fruit rot in exposed berries. Fungicide trials showed good to excellent efficacy of strobilurin fungicides against anthracnose fruit rot. A significant reduction in anthacnose fruit rot was also achieved with an application of blueberry fruit juice at the pea-size berry stage. In grapes, dormant sprays with copper, sulfur, lime sulfur and mancozeb were effective against Phomopsis cane and leaf spot. A reduced spray schedule in combination with a dormant spray was as effective as a full-season fungicide schedule. Spore trapping showed that spore numbers and viability were reduced in dormant-sprayed plots. The effects of downy mildew on photosynthesis and carbon partitioning and vine biomass were studied. Results are currently being analyzed. A reduction in photosynthesis could be measured, even before symptoms were visible. Differences in host-specificity were noted between downy mildew isolates obtained from different hosts. A nested PCR protocol for Eutypa lata and Eutypella vitis was tested in the field. Both fungi were found in the same vineyard, and occasionally on the same vines. Tests of transplant root dips with biocontrol organisms in nonfumigated fields of strawberries showed that azoxystrobin and T-10 increased yield the year after planting. Some treatments appeared harmful to the plants. An integrated program of tolerant strawberry varieties, rotation crops, compost and a biocontrol agent is being tested for management of black root rot. In raspberries, fungicide efficacy trials were done against Botrytis. Colletotrichum acutatum was found on red and black raspberries and blackberries. Isolates of C. acutatum from multiple small fruit crops (raspberries, blackberries, blueberries, cranberries, gooseberries, and grapes) were collected throughout the state. They are being tested for genetic diversity using microsatellite primers and potential for cross-infection of other small fruit crops.

Impacts
A better understanding of the identity and biology of small fruit pathogens will help growers use the most appropriate fungicides and optimize fungicide timing for the diseases they are trying to control. Data on the effects of diseases on plant growth, fruit yield and quality will aid growers in making control decisions. Studies on the environmental requirements for infection are expected to form the bases of disease-forecasting models that use weather data to predict infection periods. This will hopefully result in a reduction in fungicide applications. Efficacy testing of reduced-risk fungicides, biological control products, natural products, and inorganic substances will lead to a diversification of disease control options and reduce the dependency of blueberry growers on conventional pesticides, especially those considered 'at risk'. Identification of sources of host plant resistance and resistance mechanisms will facilitate small fruit breeding efforts to develop resistant cultivars, and will help growers adjust their management strategies to the innate resistance in their cultivars. An understanding of the effects of commonly used pesticides on non-target organisms, and of cultural practices on disease severity, will help growers choose management practices that are ecologically and biologically sound. Results from this project are expected to have environmental, worker, and consumer benefits by reducing chemical use in fruit production. The project will also help maintain short-term and long-term viability of small fruit production in the United States.

Publications

  • Olatinwo, R.O., Schilder, A.M.C., and Kravchenko, A.N. 2004. The incidence and causes of postharvest fruit rot in stored Michigan cranberries. Plant Disease 88: 1277-1282.
  • Schilder, A., Isaacs, R., Hanson, E., and Cline, B. 2004. A pocket guide to IPM scouting in highbush blueberries. MSU Extension Bulletin E-2829.
  • Wise, J.C., Gut, L.J., Isaacs, R., Schilder, A.M.C., Sundin, G.W., Zandstra, B., Hanson, E. and Shane, B. 2004. Michigan Fruit Management Guide 2005. Extension Bulletin E-154. Michigan State University, East Lansing, MI.
  • Olatinwo, R.O., Sabaratnam, S. and Schilder, A.M.C. 2004. Trichoderma stromaticum: a potential biological control agent for black root rot in strawberries. Phytopathology 94:S78.
  • Sabaratnam, S., Dickman, J. and Schilder, A.M.C. 2004. Blueberry fruit surface microflora: search for potential biocontrol agents for fruit rot pathogens. Phytopathology 94:S91.
  • Schilder, A.M.C., and Wharton, P.S. 2004. Effect of temperature on ascospore discharge of Monilinia vaccinii-corymbosi. Phytopathology 94:S92.
  • Schilder, A.M.C., Gillett, J.M. and R.W. Sysak. 2004. Evaluation of fungicides for control of foliar and fruit diseases of strawberry. Fungicide and Nematicide Tests 59:SMF030.
  • Schilder, A.M.C., Gillett, J.M. and R.W. Sysak. 2004. Evaluation of fungicides for control of foliar diseases of strawberries, 2003. Fungicide and Nematicide Tests 59:SMF029.
  • Schilder, A.M.C., Gillett, J.M. and R.W. Sysak. 2004. Evaluation of fungicides for control of postharvest fruit rots in red raspberries, 2003. Fungicide and Nematicide Tests 59:SMF028.
  • Schilder, A.M.C., Gillett, J.M., R.W. Sysak, and J.C. Wise. 2004. Evaluation of fungicides for control of foliar diseases and black rot in grapes, 2003. Fungicide and Nematicide Tests 59:SMF027.
  • Schilder, A.M.C., Gillett, J.M. and R.W. Sysak. 2004. Evaluation of dormant applications of fungicides for control of Phomopsis in grapes, 2003. Fungicide and Nematicide Tests 59:SMF026.
  • Schilder, A.M.C., Gillett, J.M. and R.W. Sysak. 2004. Evaluation of fungicides for control Phomopsis and powdery mildew in grapes. Fungicide and Nematicide Tests 59:SMF025.
  • Schilder, A.M.C., Gillett, J.M. and R.W. Sysak. 2004. Evaluation of fungicides for control of fruit rots in blueberries. Fungicide and Nematicide Tests 59:SMF024.
  • Schilder, A.M.C., Gillett, J.M. and R.W. Sysak. 2004. Evaluation of fungicides for control of mummy berry in blueberries. Fungicide and Nematicide Tests 59:SMF023.


Progress 01/01/03 to 12/31/03

Outputs
In blueberries, mummy berry apothecia survived longest when grown at temperatures of 10-15C. Temperatures of 20-25C resulted in higher daily numbers of spores released, but apothecia collapsed in a few days. Frost events below -6C were damaging to mummy berry apothecia. Colletotrichum acutatum and Phomopsis vaccinii were found to overwinter in live buds. The infection process by C. acutatum was slowed considerably in the resistant cultivar Elliott and almost no acervuli formed, compared to abundant production of acervuli in the susceptible cultivar Jersey. Characterization of microbial populations on blueberry fruit surfaces showed a prevalence of yeasts and fungi, although various bacteria were also identified. C. acutatum, Aureobasidium pullulans, and Cladosporium spp. were most prevalent. Several post-harvest treatments with several products, incl. bleach, were effective in reducing microbial levels after harvest. Pre-harvest sprays of Cabrio significantly reduced latent anthracnose infections in blueberry fruit. Sprays of a foliar fertilizer showed a reduction in anthracnose levels. In grapes, early-season fungicide sprays were found to be important for Phomopsis control, but sprays at and right after bloom were also needed. Yield loss was mostly due to berries dropping to the ground, which correlated well with the % rachis infected and the % berries infected at harvest. A pruning trial showed that minimal pruning resulted in highest losses due to Phomopis, followed by hedging. Hudson River Umbrella and Unmbrella Kniffin training systems had the lowest yield losses, especially with retaining of low bud numbers. Phomopsis spore release was monitored in vines that were covered with plastic to simulate a dry spring. This did not result in increased spore production later in the season. Single dormant sprays with lime sulfur, sulfur, Topsin M, Kocide and Stylet Oil significantly reduced Phomopsis symptoms. In our trial on effects of downy mildew on vine growth and yield, the disease showed up too late to have any measurable effect. However, a reduction in photosynthesis could be measured, even before symptoms were visible. Differences in host-specificity were noted between downy mildew isolates. Several promising new fungicides were identified in fungicide efficacy trials. Black rot in Concord grapes was controlled well with sprays at the bloom and post-bloom period. Specific PCR primers were developed for Eutypa lata and Eutypella vitis, two fungi found on grapes with Eutypa dieback in Michigan. Field tests of transplant root dips with biocontrol organisms for control of black root rot in strawberries did not appear as promising as greenhouse trials. Regular fungicides and composts are also being tested. In raspberries, good disease control with fungicides improved winter survival.

Impacts
A better understanding of the identity and biology of small fruit pathogens will help growers use the most appropriate fungicides and optimize fungicide timing for the diseases they are trying to control. Data on the effects of diseases on plant growth, fruit yield and quality will aid growers in making control decisions. Studies on the environmental requirements for infection are expected to form the bases of disease-forecasting models that use weather data to predict infection periods. This will hopefully result in a reduction in fungicide applications. Efficacy testing of reduced-risk fungicides, biological control products, natural products, and inorganic substances will lead to a diversification of disease control options and reduce the dependency of blueberry growers on conventional pesticides, especially those considered 'at risk'. Identification of sources of host plant resistance and resistance mechanisms will facilitate small fruit breeding efforts to develop resistant cultivars, and will help growers adjust their management strategies to the innate resistance in their cultivars. An understanding of the effects of commonly used pesticides on non-target organisms, and of cultural practices on disease severity, will help growers choose management practices that are ecologically and biologically sound. Results from this project are expected to have environmental, worker, and consumer benefits by reducing chemical use in fruit production. The project will also help maintain short-term and long-term viability of small fruit production in the United States.

Publications

  • Schilder, A.M.C., Gillett, J.M., and Sysak, R.W. 2003. Evaluation of fungicides for control of powdery mildew and Botrytis bunch rot in grapes, 2002. Fungicide and Nematicide Tests 58:SMF042.
  • Schilder, A.M.C., Gillett, J.M., and Sysak, R.W. 2003. Evaluation of fungicides for control of foliar diseases of strawberries, 2002. Fungicide and Nematicide Tests 58:SMF043.
  • Wharton, P., and Schilder, A. 2003. Blueberry Fruit Rot Identification Guide. Michigan Blueberry Facts. Extension Bulletin E-2847. Michigan State University, East Lansing, MI. 4 pp.
  • Olatinwo, R.O., and Schilder, A.M.C. 2003. First assessment of fruit diseases in cranberry beds in Michigan. Plant Disease 87:550-556.
  • Schilder, A.M.C., Gillett, J.M., Byrne, J.M., and Zabadal, T.J. 2003. First report of tobacco ringspot virus in table grapes in Michigan. Plant Disease 87:1149.
  • Isaacs, R., Schilder, A., Zabadal, T., and Weigle, T. 2003. A pocket guide for Grape IPM Scouting in the North Central and Eastern U.S. Extension Bulletin E-2889, Michigan State University, East Lansing, MI. 110 pp.
  • Wise, J.C., Gut, L.J., Isaacs, R., Schilder, A.M.C., Zandstra, B., Hanson, E., and Shane, B. 2003. Michigan Fruit Management Guide 2004. Extension Bulletin E-154. Michigan State University, East Lansing, MI. 173 pp.
  • Wharton, P.S., and Schilder, A.M.C. Infection and colonization of blueberry fruit by Colletotrichum acutatum. 2001. Phytopathology 93:S90 (abstr.).
  • Schilder, A.M.C., Butterworth, S.C., and Catal, M.C. 2001. Eutypa dieback progression and detection of the pathogen in grapevines. Phytopathology 93:S76 (abstr.).
  • Schilder, A.M.C., Gillett, J.M., and Sysak, R.W. 2003. Evaluation of fungicides for control of foliar diseases of strawberries, 2002. Fungicide and Nematicide Tests 58:SMF043.
  • Schilder, A.M.C., Gillett, J.M., and Sysak, R.W. 2003. Evaluation of fungicides for control of fruit rot in cranberries, 2002. Fungicide and Nematicide Tests 58:SMF013.
  • Schilder, A.M.C., Gillett, J.M., and Sysak, R.W. 2003. Evaluation of fungicides for contol of Botrytis gray mold in red raspberries, 2002. Fungicide and Nematicide Tests 58:SMF014.
  • Schilder, A.M.C., Gillett, J.M., and Sysak, R.W. 2003. Evaluation of fungicides for control of Botrytis gray mold in red raspberry, 2001. Fungicide and Nematicide Tests 58:SMF021.
  • Schilder, A.M.C., Gillett, J.M., and Sysak, R.W. 2003. Evaluation of fungicides for control of Phomopsis twig blight and fruit rot in blueberries, 2002. Fungicide and Nematicide Tests 58:SMF037.
  • Schilder, A.M.C., Gillett, J.M., and Sysak, R.W. 2003. Evaluation of fungicides for control of anthracnose fruit rot in blueberries, 2002. Fungicide and Nematicide Tests 58:SMF038.
  • Schilder, A.M.C., Gillett, J.M., and Sysak, R.W. 2003. Evaluation of fungicides for control of mummy berry in blueberries, 2002. Fungicide and Nematicide Tests 58:SMF039.
  • Schilder, A.M.C., Gillett, J.M., and Sysak, R.W. 2003. Evaluation of fungicides for control of foliar and fruit diseases in grapes, 2002. Fungicide and Nematicide Tests 58:SMF040.
  • Schilder, A.M.C., Gillett, J.M., Sysak, R.W. and Wise, J.C. 2003. Evaluation of fungicides for control of black rot and powdery mildew in grapes, 2002. Fungicide and Nematicide Tests 58:SMF041.
  • Schilder, A. 2003. Blueberry freeze injury or Phomopsis?. Fruit Crop Advisory Team Alert 18 (4).
  • Schilder, A. 2003. Topsin M Section 18 granted for blueberries. Fruit Crop Advisory Team Alert 18 (5).
  • Schilder, A. 2003. Gray mold control in strawberries. Fruit Crop Advisory Team Alert 18 (6).
  • Schilder, A. 2003. Elevate receives 2(ee) recommendation for suppression of mummy berry in blueberry. Fruit Crop Advisory Team Alert 18 (6).
  • Schilder, A. 2003. Switch, a new fungicide for berry crops. Fruit Crop Advisory Team Alert 18 (1).
  • Schilder, A. 2003. Cabrio, a broad-spectrum fungicide for berry crops. Fruit Crop Advisory Team Alert 18 (1).
  • Schilder, A. 2003. Mummy berry update for blueberry growers. Fruit Crop Advisory Team Alert 18 (2).
  • Schilder, A. 2003. Focus on early sprays for Phomopsis control in grapes. Fruit Crop Advisory Team Alert 18 (3).
  • Schilder, A. 2003. Indar Section 18 granted for blueberries in 2003. Fruit Crop Advisory Team Alert 18 (3).
  • Schilder, A. 2003. Downy mildew sighted in grapes. Fruit Crop Advisory Team Alert 18 (11).
  • Schilder, A. 2003. Michigan blueberry fact sheets published. Fruit Crop Advisory Team Alert 18 (11).
  • Schilder, A. 2003. Battling Botrytis in fall raspberries. Fruit Crop Advisory Team Alert 18 (13).
  • Schilder, A. 2003. Is it a virus disease or something else? A few pointers. Fruit Crop Advisory Team Alert 18 (13).
  • Schilder, A. 2003. Small fruit disease update. Fruit Crop Advisory Team Alert 18 (14).
  • Schilder, A. 2003. Botrytis bunch rot control in grapes. Fruit Crop Advisory Team Alert 18 (16).
  • Schilder, A. 2003. What is wrong with my raspberries? Fruit Crop Advisory Team Alert 18 (17).
  • Schilder, A. 2003. Overview of grape diseases during the 2003 growing season. Fruit Crop Advisory Team Alert 18 (18).
  • Wise, J., Schilder, A., Isaacs, R., and Zandstra. B. 2003. Minor-use crop pesticide prioritization in the 2003 IR-4 Food Use Workshop. Crop Advisory Team Alert 18 (18).
  • Tritten, B., Hanson, E., Schilder, A., and Thornton, G. 2003. Winter injury in raspberry. Fruit Crop Advisory Team Alert 18 (7).
  • Schilder, A. 2003. Angular leaf spot showing up in strawberries. Fruit Crop Advisory Team Alert 18 (7).
  • Schilder, A. 2003. Bloom: start of a critical period for black rot control in grapes. Fruit Crop Advisory Team Alert 18 (8).
  • Schilder, A. 2003. Rainy weather conducive to phomopsis development in grapes. Fruit Crop Advisory Team Alert 18 (9).
  • Schilder, A. 2003. New options for control of fruit rots in blueberries. Fruit Crop Advisory Team Alert 18 (10).
  • Longstroth, M., Isaacs, R., and Schilder, A. 2003. Blueberry shoestring virus in Michigan. Fruit Crop Advisory Team Alert 18 (10).


Progress 01/01/02 to 12/31/02

Outputs
Fungicide timing trials showed that early-season sprays were particularly important for Phomopsis control. Yield loss was mostly due to berries dropping to the ground and was best correlated with lesion size on the cluster rachis. Maximum yield losses were estimated to be 1.5-2 tons per acre. A pruning trial showed that minimal pruning resulted in highest losses due to Phomopis, followed by hedging. Hudson River Umbrella and Unmbrella Kniffin training systems had the lowest yield losses, especially with retaining of low bud numbers. Phomopsis spore release was monitored in vines that were covered with plastic for 6 weeks to simulate a dry spring. This resulted in lower spore release than the control from the time that the plastic was removed. In our trial studying the effects of downy mildew on vegetative growth, yield, and fruit quality, the disease showed up too late to have any measurable effects on the chosen variables. However, effects on photosynthesis could be measured. Fungicide efficacy trials were conducted for testing control of downy mildew, powdery mildew, black rot, Phomopsis, and Botrytis. Several promising products were identified. For the third year in a row, black rot in Concord grapes was controlled well with a spray schedule targeting the bloom and post-bloom period. In studies on blueberry fruit rot fungi, Colletotrichum acutatum showed two distinct spore peaks, one around early to mid fruit development (later than in 2001 because of an extended cold period), the other at fruit maturity. Both C. acutatum and Phomopsis vaccinii were found to overwinter in live buds, which suggest the need to control fall infections. Studies continue on the infection process and mechanism of resistance to anthracnose fruit rot. Reduced-risk fungicides and reduced spray programs were tested for efficacy in controlling blueberry diseases. A program targeting fungicide sprays after frost events was better at controlling mummy berry than a standard program. An on-farm trial of Abound showed that pre-harvest sprays significantly reduced latent anthracnose infections in blueberry fruit. Characterization of microbial populations on blueberry fruit surfaces showed a prevalence of yeasts and fungi, although bacteria were also identified. Altogether, about 20-30 different organisms were detected. Identification of these strains is in progress. Studies on the black root rot complex in the northeastern US continue in collaboration with the USDA Beltsville, Cornell University, and Penn State University. Field tests of transplant root dips with biocontrol organisms did not appear as promising as greenhouse trials. Addition of yard waste compost was detrimental to the strawberry plants, possibly by exacerbating drought stress. Fungicide efficacy and timing trials were conducted in raspberries and cranberries. Serenade was fairly effective at controlling early rot and bitter rot in cranberries, but only when applied in a post-bloom program.

Impacts
A better understanding of the identity and biology of small fruit pathogens will help growers use the most appropriate fungicides and optimize fungicide timing for the diseases they are trying to control. Data on the effects of diseases on plant growth, fruit yield and quality will aid growers in making control decisions. Studies on the environmental requirements for infection are expected to form the bases of disease-forecasting models that use weather data to predict infection periods. This will hopefully result in a reduction in fungicide applications. Efficacy testing of reduced-risk fungicides, biological control products, natural products, and inorganic substances will lead to a diversification of disease control options and reduce the dependency of blueberry growers on conventional pesticides, especially those considered 'at risk'. Identification of sources of host plant resistance and resistance mechanisms will facilitate small fruit breeding efforts to develop resistant cultivars, and will help growers adjust their management strategies to the innate resistance in their cultivars. An understanding of the effects of commonly used pesticides on non-target organisms, and of cultural practices on disease severity, will help growers choose management practices that are ecologically and biologically sound. Results from this project are expected to have environmental, worker, and consumer benefits by reducing chemical use in fruit production. The project will also help maintain short-term and long-term viability of small fruit production in the United States.

Publications

  • Schilder, A.M.C., Gillett, J.M., and Sysak, R.W. 2002. Evaluation of fungicides for control of Phomopsis diseases in blueberries, 2001. Fungicide and Nematicide Tests 57 (electronic version).
  • Schilder, A.M.C., Gillett, J.M., and Sysak, R.W., and Wise, J.C. 2002. Evaluation of fungicides for control of foliar and fruit diseases in Niagara grapes, 2001. Fungicide and Nematicide Tests 57 (electronic version)
  • Schilder, A.M.C., Gillett, J.M., Wise, J.C., and Sysak, R.W. 2002. Evaluation of fungicides for control of black rot and powdery mildew in Concord grapes, 2001. Fungicide and Nematicide Tests 57 (electronic version).
  • Schilder, A.M.C., Gillett, J.M., and Sysak, R.W. 2002. Evaluation of fungicides for downy mildew in grapes, 2001. Fungicide and Nematicide Tests 57 (electronic version).
  • Schilder, A.M.C., Gillett, J.M., and Sysak, R.W. 2002. Evaluation of fungicides for control of foliar, cane, and post-harvest diseases of red raspberry, 2001. Fungicide and Nematicide Tests 57 (electronic version).
  • Schilder, A.M.C., Gillett, J.M., and Sysak, R.W. 2002. Evaluation of fungicides for control of calyx and fruit diseases of strawberry, 2001. Fungicide and Nematicide Tests 57 (electronic version).
  • Schilder, A.M.C., Gillett, J.M., and Sysak, R.W. 2002. Evaluation of fungicides for control of foliar diseases of strawberry, 2001. Fungicide and Nematicide Tests 57 (electronic version).
  • Schilder, A.M.C., Gillett, J.M., and Sysak, R.W. 2002. Evaluation of fungicides for control of post-harvest fruit rots in strawberry, 2001. Fungicide and Nematicide Tests 57 (electronic version).
  • Schilder, A.M.C. 2002. Abound label expanded to blueberries and other bushberries. Fruit Crop Advisory Team Alert 17 (1): 4-5.
  • Schilder, A.M.C. 2002. Indar Section 18 granted for blueberries in 2002. Fruit Crop Advisory Team Alert 17 (2): 6-7.
  • Schilder, A.M.C. 2002. Quadris fungicide labeled for strawberries. Fruit Crop Advisory Team Alert 17 (3): 4-5.
  • Isaacs, R., and Schilder, A.M.C. 2002. Pest management in frost-damaged vineyards. Fruit Crop Advisory Team Alert 17 (4): 4-7.
  • Landis, J.N., Sanchez, J.E., Bird, G.W., Edson, C.E., Isaacs, R., Lehnert, R.H., Schilder, A.M.C., and Swinton, S.M. (eds). 2002. Fruit Crop Ecology and Management. Extension Bulletin E-2759. Michigan State University, East Lansing, Mich. 101 pp.
  • Gut, L.J., Isaacs, R., Schilder, A.M.C, and McManus, P.S. 2002. The community. Pages 34-62 in: Fruit Crop Ecology and Management. Landis, J.N., Sanchez, J.E., Bird, G.W., Edson, C.E., Isaacs, R., Lehnert, R.H., Schilder, A.M.C., and Swinton, S.M. (eds). Extension Bulletin E-2759. Michigan State University, East Lansing, Mich.
  • Schilder, A.M.C., Isaacs, R., Gut, L.J., Andresen, J.A., McManus, P.S., and Mallampalli, N. 2002. Environmental effects on insects and diseases. Pages 62-74 in: Fruit Crop Ecology and Management. Landis, J.N., Sanchez, J.E., Bird, G.W., Edson, C.E., Isaacs, R., Lehnert, R.H., Schilder, A.M.C., and Swinton, S.M. (eds). Extension Bulletin E-2759. Michigan State University, East Lansing, Mich.
  • Isaacs, R., Mallampalli, N., Gut, L.J., Schilder, A.M.C., and McManus, P.S. 2002. Influence of surrounding landscapes on pest management. Pages 75-81 in: Fruit Crop Ecology and Management. Landis, J.N., Sanchez, J.E., Bird, G.W., Edson, C.E., Isaacs, R., Lehnert, R.H., Schilder, A.M.C., and Swinton, S.M. (eds). Extension Bulletin E-2759. Michigan State University, East Lansing, Mich.
  • Schilder, A.M.C.,, Gillett, J.M., and Woodworth, J.A. 2002. The kaleidoscopic nature of blueberry fruit rots. Proceedings 7th International Symposium on Vaccinium. R.F. Hepp (ed.). Acta Horticulturae 574: 81-83.
  • Schilder, A.M.C., Olatinwo, R.O., and Hanson, E.J. 2002. Fruit rots are common in Commercial Cranberry Beds in Michigan, USA. Proceedings 7th International Symposium on Vaccinium. R.F. Hepp (ed.). Acta Horticulturae 574: 81-83.
  • Schilder, A.M.C., Gillett, J.M., and Sysak, R.W. 2002. Evaluation of fungicides for control of mummy berry in blueberries, 2001. Fungicide and Nematicide Tests 57 (electronic version).
  • Schilder, A.M.C. 2002. Section 18 for Topsin M will help fill Benlate void in blueberries. Fruit Crop Advisory Team Alert 17 (5): 1-2.
  • Schilder, A.M.C. 2002. Mitigating the risk of spring frost injury in grapes. Fruit Crop Advisory Team Alert 17 (6): 2.
  • Schilder, A.M.C., and Tritten, R. 2002. Disease control increases winter survival of summer raspberries. Fruit Crop Advisory Team Alert 17 (7): 3.
  • Schilder, A.M.C. 2002. Quarantine established to keep blueberry viruses out of Michigan. Fruit Crop Advisory Team Alert 17 (9): 3.
  • Schilder, A.M.C. 2002. Phomopsis lesions on grape foliage an indicator of inoculum potential. Fruit Crop Advisory Team Alert 17 (10): 3.
  • Schilder, A.M.C. 2002. Reduced-risk fungicide Switch labeled for strawberries. Fruit Crop Advisory Team Alert 17 (12): 6.
  • Schilder, A.M.C. 2002. Elevate fungicide labeled for use in bushberries and caneberries. Fruit Crop Advisory Team Alert 17 (12): 6-7 .
  • Schilder, A.M.C. 2002. Phomopsis twig blight common sight in Michigan blueberries. Fruit Crop Advisory Team Alert 17 (12): 7.
  • Schilder, A.M.C. 2002. Differences between Topsin M and Benlate labels for blueberries. Fruit Crop Advisory Team Alert 17 (13): 3.
  • Schilder, A.M.C. 2002. Control of Botrytis gray mold in brambles. Fruit Crop Advisory Team Alert 17 (14): 3.
  • Schilder, A.M.C. 2002. Mid-summer small fruit disease update. Fruit Crop Advisory Team Alert 17 (15): 4-5.
  • Schilder, A.M.C. 2002. Is late-season disease control needed in grapes. Fruit Crop Advisory Team Alert 17 (16): 4-5.
  • Schilder, A.M.C. 2002. Gray mold control in fall raspberries. Fruit Crop Advisory Team Alert 17 (17): . Wise, J., Schilder, A., Isaacs, R., and Zandstra, B., 2002. Minor use crop pesticide prioritization in the 2002 IR-4 Food Use Workshop. Fruit Crop Advisory Team Alert 17 (18): .
  • Schilder, A.M.C. 2002. How much are you actually losing to Phomopsis? Michigan Grape Society Newsletter, November 2002.


Progress 01/01/01 to 12/31/01

Outputs
In 2001, the observed incidence of Eutypa infection in our study vineyard was much greater than in previous years. Eutypa greatly reduced vegetative growth and fruit yield on infected shoots, but only slightly reduced fruit quality. Spore release of Phomopsis viticola in grape peaked early to mid season, after which spore levels declined drastically. Two genetically distinct groups could be identified in the Phomopsis viticola population based on DNA sequence similarity. Cultural morphology and virulence also varied. Downy mildew resulted in premature defoliation of grapes. While yields were reduced, brix increased because of increased sun exposure which promoted ripening. Photosynthetic capacity of leaf tissues decreased linearly with increasing downy mildew severity to below zero at 100% disease. In studies on blueberry fruit rot fungi, Alternaria alternata spores substantially increased at fruit maturity, whereas C. acutatum showed two distinct spore peaks, one around flowering/early fruit development, the other at fruit maturity. Knowledge of spore dispersal can help growers optimize timing of fungicide sprays. New and reduced-risk fungicides, biological control products, induced resistance products, plant extracts, salts and oils, as well as reduced spray programs were tested for efficacy in controlling fungal and bacterial diseases in grapes, blueberries, strawberries, and raspberries. Many of the 'safer' products suppressed diseases, but were often outperformed by conventional chemicals. The strobilurins (BAS 500 and 516) were excellent broad-spectrum materials in every crop tested. They controlled blueberry and strawberry anthracnose, strawberry scorch, raspberry foliar and cane diseases. BAS 510, Switch and Elevate also had good activity against Botrytis. Armicarb (potassium bicarbonate) did surprisingly well against black rot, and Gavel (Zoxium and Dithane) provided excellent control of downy mildew in grapes. Phomopsis in grapes was best controlled with programs containing strobilurins like Flint and Abound. The most effective fungicide against mummy berry remains Indar (fenbuconazole). Serenade, a biofungicide, showed promise against downy mildew in grapes. Reduced spray programs provided poor control of mummy berry and blueberry anthracnose, but were excellent against grape black rot. We found that some wild strawberry genotypes show resistance to black root rot based on fruit yields and runner production. The black root rot pathogen complex varies greatly from site to site, however, Rhizoctonia, Pythium, and Idriella spp., and nematodes are most common. Addition of compost improves growth and yield of plants in infested soils. Transplant root dips with commercial biocontrol products reduced root lesions and increased plant growth in infested soils. Cranberry fruit rot levels were low in 2001 because of the dry weather. The composition of the pathogen complex is variable from year to year. However, Colletotrichum spp. tend to be predominant. Incidence of fungi like Fusicoccum, Coleophoma, and Allantophomopsis increased sharply during storage.

Impacts
A better understanding of the identity and biology of small fruit pathogens will help growers use the most appropriate fungicides and optimize fungicide timing for the diseases they are trying to control. Data on the effects of diseases on plant growth, fruit yield and quality will aid growers in making control decisions. Studies on the environmental requirements for infection are expected to form the bases of disease-forecasting models that use weather data to predict infection periods. This will hopefully result in a reduction in fungicide applications. Efficacy testing of reduced-risk fungicides, biological control products, natural products, and inorganic substances will lead to a diversification of disease control options and reduce the dependency of blueberry growers on conventional pesticides, especially those considered 'at risk'. Identification of sources of host plant resistance and resistance mechanisms will facilitate small fruit breeding efforts to develop resistant cultivars, and will help growers adjust their management strategies to the innate resistance in their cultivars. An understanding of the effects of commonly used pesticides on non-target organisms, and of cultural practices on disease severity, will help growers choose management practices that are ecologically and biologically sound. Results from this project are expected to have environmental, worker, and consumer benefits by reducing chemical use in fruit production. The project will also help maintain short-term and long-term viability of small fruit production in the United States.

Publications

  • Schilder, A. 2001. Small fruit disease update. Fruit Crop Advisory Team Alert 16 (16): 5-6.
  • Schilder, A. 2001. Grape diseases: overview of the 2001 season. Fruit Crop Advisory Team Alert 16 (18): 1-2.
  • Hancock, J.F., Finn. C.A., Hokanson, S.C., Luby, J.J., Goulart, B.L., Demchak, K., Callow, P.W., Serce. S., Schilder, A., Hummer. K.E. 2001. A multi-state comparison of native octoploid strawberries from North and South America. J. Amer. Soc. of Hortic. Sci. 126: 579-586.
  • Olatinwo, R.O., and Schilder, A.M.C. Progression of rot in stored cranberries. 2001. Phytopathology 91: S 67 (abstr.)
  • Rogers, J., Schilder, A.M.C., and Jarosz, A.M. 2001. Measuring patchiness in diseases caused by Phomopsis viticola and P. vaccinii using the information fractal dimension. Phytopathology 91: S77 (abstr.)
  • Rogers, J., Schilder, A.M.C., and Sysak, R.W. 2001. Seasonal patterns of spore release in Phomopsis viticola in grapes. Phytopathology 91: S77 (abstr.)
  • Schilder, A.M.C., Gillett, J.M., and Sysak, R.W. 2001. Evaluation of fungicides for control of mummy berry in blueberries, 2000. Fungicide and Nematicide Tests 56 (electronic version).
  • Schilder, A.M.C., Gillett, J.M., and Sysak, R.W. 2001. Evaluation of fungicides for control of Phomopsis diseases in blueberries, 2000. Fungicide and Nematicide Tests 56 (electronic version).
  • Schilder, A.M.C., Gillett, J.M., and Sysak, R.W. 2001. Evaluation of fungicides for control of anthracnose fruit rot in blueberries, 2000. Fungicide and Nematicide Tests 56 (electronic version).
  • Schilder, A.M.C., Gillett, J.M., and Wise, J.C. 2001. Evaluation of fungicides for control of foliar diseases in grapes, 2000. Fungicide and Nematicide Tests 56 (electronic version).
  • Schilder, A.M.C., Gillett, J.M., and Wise, J.C. 2001. Evaluation of fungicides for control of black rot in grapes, 2000. Fungicide and Nematicide Tests 56 (electronic version).
  • Schilder, A.M.C., Gillett, J.M., and Sysak, R.W. 2001. Evaluation of fungicides for control of Phomopsis and black rot in grapes, 2000. Fungicide and Nematicide Tests 56 (electronic version).
  • Schilder, A.M.C., Gillett, J.M., and Sysak, R.W. 2001. Evaluation of fungicides for control of downy mildew and powdery mildew in grapes, 2000. Fungicide and Nematicide Tests 56 (electronic version).
  • Schilder, A.M.C., Gillett, J.M., and Sysak, R.W. 2001. Evaluation of fungicides for Botrytis bunch rot control in grapes, 2000. Fungicide and Nematicide Tests 56 (electronic version).
  • Schilder, A.M.C., Gillett, J.M., and Sysak, R.W. 2001. Fungicide efficacy in controlling Phomopsis in grapes, 2000 Fungicide and Nematicide Tests 56 (electronic version).
  • Schilder, A.M.C., Gillett, J.M., and Sysak, R.W. 2001. Evaluation of fungicides for downy mildew control in grapes, 2000. Fungicide and Nematicide Tests 56 (electronic version).
  • M. Longstroth and A. Schilder. 2001.Blueberry fungicide efficacy trials in 2000. 2001. 130th Annual Report of the Secretary of the State Horticultural Society of Michigan for the year 2000.
  • Gut, L.J., Isaacs, R.,Wise, J.C., Jones, A.L., Schilder, A.M.C., Zandstra, B., and Hanson, E. 2001. Fruit Spraying Calendar 2002.
  • Schilder, A. 2001. Can lime sulfur be used to control Phomopsis in blueberries? Fruit Crop Advisory Team Alert 16 (1): 1-2.
  • Schilder, A. 2001. Emergency exemption issued for Indar in blueberries for 2001. Fruit Crop Advisory Team Alert 16 (2): 2-3.
  • Schilder, A. 2001. Phomopsis is competing for your grapes. Fruit Crop Advisory Team Alert 16 (3): 4-5.
  • Schilder, A. 2001. Dupont to phase out production of Benlate. Fruit Crop Advisory Team Alert 16 (3): 5
  • Schilder, A. 2001. Bravo 24-C label extended for disease control in blueberries. Fruit Crop Advisory Team Alert 16 (4): 1
  • Schilder, A. 2001. Fungicide and antibiotic resistance workshop. Fruit Crop Advisory Team Alert 16 (7): 2-3.
  • Schilder, A. 2001. Immediate prebloom and bloom: a critical period for disease control in grapes. Fruit Crop Advisory Team Alert 16 (8): 1-2.
  • Schilder, A. 2001. Anthracnose fruit rot in strawberries. Fruit Crop Advisory Team Alert 16 (13): 4-5.
  • Schilder, A. 2001. Leather rot showing up in strawberries. Fruit Crop Advisory Team Alert 16 (12):4-5.
  • Schilder, A. 2001. Raspberries and blackberries get fireblight, too. Fruit Crop Advisory Team Alert 16 (14): 1.


Progress 01/01/00 to 12/31/00

Outputs
Spore release by Alternaria spp. which cause Alternaria fruit rot of blueberries, was monitored and found to coincide with early fruit maturation. A conventional fungicide program decreased anthracnose fruit rot but increased Alternaria fruit rot. Overhead irrigation was found to somewhat increase blueberry fruit rots. Colletotrichum acutatum, not C. gloeosporioides, was the pathogen associated with anthracnose fruit rot in Michigan. This was confirmed for representative isolates by PCR using species-specific primers. Selected C. acutatum isolates were tested by PCR using microsatellite primers. Three different banding patterns were detected. Many other fungi, some previously unreported on blueberries, were also found. In 2000, repeated samples of mature fruit were taken from three blueberry cultivars on 9 farms to study the dynamics of fruit rot development. Anthracnose incidence increased over the course of the season, while incidence of other pathogens decreased. In a fungicide trial, there was an inverse relationship between incidence of anthracnose fruit rot and Alternaria and Botrytis fruit rot levels. Few fungicides controlled more than one fruit-rotting pathogen. In vitro tests were conducted to assess the fungicide sensitivity of C. acutatum, Alternaria spp., and Botrytis cinerea. New and reduced-risk fungicides, biofungicides, and plant defense boosters were tested for mummy berry control. Indar (an SI fungicide) was the most effective. Reduced spray schedules were as effective as full spray schedules. The biofungicide Serenade also looked promising for mummy berry control. The use of a wood-chip mulch in an on-farm trial did not significantly reduce mummy berry shoot strike incidence, but suppressed the emergence of cranberry fruit worm early in the season. Trials were also conducted to test the efficacy of new products for control of common grape and strawberry diseases. Several promising materials were identified, including a plant defense booster. Spore production of Phomopsis viticola was monitored at two infected vineyard sites. Spore catches peaked in May and June and then tapered off. The genetic and morphological characterization of P. viticola isolates from MI, OH, NY, and PA has been initiated. The relationship between Eutypa dieback symptom severity and vegetative growth and yield was studied in Concord grape. Most growth and yield components, but not juice quality, were affected. An integrated crop management approach, which incorporated non-EBDC fungicides, lower application rates with improved sprayers, a reduced number of fungicide applications, and pheromone technology for insect control, was equivalent to a conventional spray program for control of major diseases in juice and wine grapes. A survey was conducted to determine the incidence of fruit rots in MI cranberry beds. Incidence ranged from 1-91% (average 26%). Among the many fungi isolated from rotted berries, the main pathogens were: Phyllosticta vaccinii (early rot), Colletotrichum acutatum, and Pestalotia vaccinii.

Impacts
The project so far has achieved a better understanding of the identity of individual pathogens and their relative contributions to the blueberry and cranberry fruit rot complexes in Michigan. We have also identified several promising avenues for optimization of control, such as the use of more effective fungicides (including biofungicides), reduced spray schedules, and cultural control methods.

Publications

  • Schilder, A.M.C. 2000. Eradication. Pages 421-423. Encyclopedia of Plant Pathology (O.C. Maloy and T.D. Murray, editors), John Wiley & Sons.
  • Hanson, E., Hancock, J., Ramsdell, D.C., Schilder, A., VanEe, G., and Ledebuhr, R. 2000. Sprayer type and pruning affect the incidence of blueberry fruit rots. Hort Science 35:235-238.
  • Hancock, J., Callow, P., Schilder, A., and Cerce, S. 2000. Relative performance of strawberry cultivars and Fragaria virginiana hybrids on fumigated and non-fumigated soil in Michigan. J. Amer. Soc. of Hortic. Sci. (in press)
  • Schilder, A.M.C., Gillett, J.M., and Sysak, R. 2000. Evaluation of fungicides for control of mummy berry in blueberry, 1999. Fungicide and Nematicide Tests 55: 85-86.
  • Schilder, A.M.C., Gillett, J.M., and Sysak, R. 2000. Evaluation of fungicides for control of Phomopsis twig blight of blueberry, 1999. Fungicide and Nematicide Tests 55: 87-88.
  • Schilder, A.M.C., Gillett, J.M., and Sysak, R. 2000. Comparison of fungicides for management of foliar diseases of blueberry, 1999. Fungicide and Nematicide Tests 55: 84.
  • Schilder, A.M.C., Gillett, J.M., and Sysak, R. 2000. Chemical control of anthracnose fruit rot in blueberry, 1999. Fungicide and Nematicide Tests 55: 83.
  • Schilder, A.M.C., Gillett, J.M., and Sysak, R. 2000. Relative performance of fungicides for control of powdery mildew of grape, 1999. Fungicide and Nematicide Tests 55: 106-107.
  • Schilder, A.M.C., Gillett, J.M., and Sysak, R. 2000. Evaluation of fungicides for control of Phomopsis cane and leaf spot of grape, 1999. Fungicide and Nematicide Tests 55: 105.
  • Schilder, A.M.C., Gillett, J.M., and Sysak, R. 2000. Evaluation of fungicides for control of downy mildew of grape, 1999. Fungicide and Nematicide Tests 55: 104.
  • S.C. Butterworth and A.M.C. Schilder. 2000. Effects of Eutypa dieback on yield components in Concord grapes in Michigan. Phytopathology 90: S11.
  • R.O. Olatinwo and A.M.C. Schilder. 2000. Incidence of fruit-rotting fungi in commercial cranberry beds in Michigan in 1999. Phytopathology 90: S57.
  • Schilder, A.M.C. 2000. Managing root diseases of Michigan strawberries. 129th Annual Report of the Secretary of the State Horticultural Society of Michigan for the year of 1999 (ISSN 0096-7688).
  • Schilder, A.M.C. 2000. Grape fungicide trials in Michigan. 129th Annual Report of the Secretary of the State Horticultural Society of Michigan for the year of 1999 (ISSN 0096-7688).