Source: MICHIGAN STATE UNIV submitted to NRP
MULTI-FACETED APPROACH FOR SOIL DETECTION AND MANAGEMENT OF PYTHIUM AND PHYTOPHTHORA IN CARROT, TOMATO, CUCURBITS, AND ASPARAGUS
Sponsoring Institution
National Institute of Food and Agriculture
Project Status
COMPLETE
Funding Source
OTHER EXTENSION GRANT
Reporting Frequency
Annual
Accession No.
0216112
Grant No.
2008-51180-04881
Cumulative Award Amt.
(N/A)
Proposal No.
2009-01240
Multistate No.
(N/A)
Project Start Date
Sep 1, 2008
Project End Date
Aug 31, 2012
Grant Year
2009
Program Code
[SCRI]- Specialty Crop Research Initiative
Recipient Organization
MICHIGAN STATE UNIV
(N/A)
EAST LANSING,MI 48824
Performing Department
Plant, Soil and Microbial Science
Non Technical Summary
The goal of this project is to develop and implement an effective detection method and comprehensive management strategy for the soilborne pathogens, Phytophthora and Pythium species, which relies on multiple tools rather than intensive use of fungicides. Growers and processors rank the diseases caused by these pathogens as a top threat to production and long-term viability, especially to Cucurbitaceae and Solanaceae group vegetables (cucumber, pumpkin, squash, melon, tomato, pepper, eggplant) and most recently Fabaceae group vegetables (lima, snap and wax beans). Recent losses have become so large (individual growers have reached $2 million) that the economic viability of the vegetable industries in many states is at risk and a larger, coordinated multi-state research effort is needed. Researchers in Michigan and California will collaborate with industry partners to achieve these goals through a multi-disciplinary effort. Sub-objectives include developing fast method to detect and quantify pathogens in plant, soil, and irrigation water using PCR-based technology, developing novel production strategies (appropriate cover/rotational crops, biofumigants), identifying cultivars with genetic tolerance or growth habits that reduce disease, and optimizing the efficacy of fungicidal products (identifying effective active ingredients, optimal application, timing). Researchers linked with processors, packers, extension agents, crop consultants, and growers will deliver the research advances to the field via laboratory open houses, newsletters, and field meetings. The rate of adopting project recommendations will be measured. Through these activities, this project will be further integrated into multi-functional research and education activities that address complex pest management priorities.
Animal Health Component
50%
Research Effort Categories
Basic
40%
Applied
50%
Developmental
10%
Classification

Knowledge Area (KA)Subject of Investigation (SOI)Field of Science (FOS)Percent
2121499104010%
2121499110210%
2121499116010%
2161452104010%
2161452110210%
2161452116015%
2161429104010%
2161429110210%
2161429116015%
Knowledge Area
212 - Pathogens and Nematodes Affecting Plants; 216 - Integrated Pest Management Systems;

Subject Of Investigation
1499 - Vegetables, general/other; 1429 - Cucurbits, other; 1452 - Carrot;

Field Of Science
1040 - Molecular biology; 1160 - Pathology; 1102 - Mycology;
Goals / Objectives
The goal of this project is to develop and implement a detection and quantification method along with a comprehensive management strategy for Pythium and Phytophthora spp. using multiple tools that are integrated rather than relying on the intensive use of pesticides. Researchers will link with processors, packers, extension agents, crop consultants, and growers to transfer research advances from this project to the field via laboratory open houses, newsletters, field meetings, and demonstration field plots with commercial growers. This goal will be achieved through the following: 1. Detection and quantification of Phytophthora and Pythium spp. Use PCR-based technology to establish a fast and accurate detection and quantification system for the pathogens. 2. Cover crops and soil amendments. Test the effect of organic soil amendments and measure the susceptibility of cover crops to Phytophthora spp. and to determine their impact on disease occurrence in commercial production. 3. Resistance/tolerance. Test commercially available pumpkin and squash cultivars for characteristics that reduce crown rot and fruit rot including an architecture that opens the canopy (shortened internodes, reduced branching), produces fruit close to the crown, holds fruit off of the soil, and/or has a shortened time to maturity/harvest. Compare P. capsici-tolerant pepper cultivars with standard cultivars for use in P. capsici-infested soils to reduce the risk of crop loss. Partner with plant breeders to test lines for susceptibility. Examine the basis for age-related cucumber fruit resistance to P. capsici. 4. Fungicides. Maximize the efficacy and efficiency of fungicidal/suppressive products through: i) Determining the optimum time to apply fungicides based on fruit age, ii) Identifying effective active ingredients. 5. Extension efforts. Disseminate results through intensive contact with stakeholders including: i) Conducting local meetings, field, and demonstration trials, ii) Testing irrigation water for P. capsici, iii) Providing diagnostic and disease management assistance, and iv) Evaluating and assessing outreach programs and efforts.
Project Methods
1. Pathogen detection and quantification. Isolates of Phytophthora and Pythium spp. will be obtained from established collections and from isolations obtained from diseased plants in Michigan and California. Primers specific to these pathogens will be designed suitable for real-time PCR with the aid of DNAStar. For separating living microorganisms and dead cells in soil and water, ethidium monoazide will be used. The developed PCR protocol will be validated. For each target pathogen, the performance of the selected primer pair will be further evaluated based on traditional PCR. 2. Cover crops and soil amendments. Thirteen cover crop species will be screened for their susceptibility to P. capsici, P. capsici, and Pythium spp.. Plants will be monitored for disease symptoms. All plants will be harvested destructively for root evaluation and biomass measurement. Separate experiments will be conducted to determine if GSLs-producing plant species can be used as bio-fumigants to suppress the pathogens. GSLs-producing Brassica spp. will include included: oilseed radish, brown mustard, oriental mustard, yellow mustard, apam fumigation, and an untreated control. 3. Resistance/Tolerance. Cultivars with a shortened time to harvest will be assessed on pumpkin and squash. Forty-two varieties of tomatoes and wild relatives will be selected. Zoospores will be examined for encystment, germination, germ tube formation, length and appearance, and appresorium formation. These experiments will be performed in conjunction with genomic analyses to identify changes in gene expression in relationship to fruit age and susceptibility. Fruit will be monitored for up to 10 days for appearance of water soaking symptoms and sporulating fungus. 4. Fungicides. In field, fruit age experiments will be performed on fruit from field-grown pumpkin, yellow summer squash, green zucchini, and winter squash cultivars. Fungicides applied at the following times: initiated at flowering and reapplied every 5 days until harvest, initiated at flowering and reapplied every 7 days until harvest, initiated at flowering and reapplied every 7 days for a total of 6 applications, initiated at flowering and reapplied every 7 days for a total of 4 sprays. Promising products from these initial trials will be included in additional replicated research field plots. Spray and root application will be made to assess the efficacy of treatments for the control of above- and below-ground infection. 5. Extension efforts. We will join the biology of P. capsici with specific control strategies via local, regional, and national level on-farm meetings, demonstration plots, laboratory open houses, and printed media. Agricultural irrigation water sources will be monitored at various locations for P. capsici at the request of individual growers. Farm visits provide disease assessment and customized control recommendations and are helpful for growers struggling with P. capsici for the first time. We will evaluate outreach efforts by quantifying the success of each outreach component.

Progress 09/01/08 to 08/31/12

Outputs
OUTPUTS: 1. Twelve cover crops were studied in greenhouse and fields for controlling Phytophthora blight in vegetables. The influence of conventional, organic, and transitional farming systems on potato and carrot production and disease development was studied on microbial activity, root knot nematodes and Pythium diseases were included. Quantitative analysis of soil population of P. capsici was conducted. Green manures were incorporated into soil to create a potential disease suppressive soil. 2. Plant susceptibility to rot caused by P. capsici. Greenhouse and laboratory experiments were conducted to determine the virulence of Phytophthora capsici on pepper, slicing cucumber (Cucumis sativus), pickling cucumber (C. sativus), processing pumpkin (Cucurbita moschata), yellow squash (C. pepo), zucchini (C. pepo), butternut squash (C. moschata), and winter squash (C. maxima). 62 lines of a tomato inbred backcross population, 72 inbred line pepper population, and a worldwide germplasm collection of 384 pepper accessions were evaluated. 42 tomato varieties and wild relatives were compared for resistance/tolerance to P. capsici crown and root rot. 65 lines of a tomato inbred backcross population obtained from LA407 x Hunt100 population genetic map was generated using 152 polymorphhic markers. The presence and position of quantitative trait loci (QTLs) was determined with permutation tests that establish the empirical significance thresholds of QTL mapping with the interval mapping LRS. Pyrosequencing was performed on cucumber fruit peel samples. The full cucumber germplasm collection (1296 PIs) was screened. BLAST analysis provided putative homologs for 95% of the contigs represented by >30 ESTs and was used to assign putative gene functions. 3. Twelve field trials with 191 treatment regimes tested the efficacy and optimal conditions of products for efficacy against P. capsici of cucurbits and pepper. The genetic structure of 106 P. capsici isolates collected from a field adjacent to a creek used for irrigation and from the creek itself were evaluated using six polymorphic nuclear loci. Processing pumpkin and winter squash were evaluated for age-related resistance. Effective active ingredients have been screened against P. capsici, P. asparagi, and Pythium spp. Numerous yearly replicated efficacy trials tested at least 35 registered and unregistered fungicides were examined. 4. Each year, multiple field tours were organized for growers, extension educators, industry leaders, and policy makers, including cover crop, variety, and fungicide trials. Presentations were made at various meetings including: the West Central Spring Horticulture meeting in Hart, MI, the Fruit and Vegetable Grower Association of Delaware Ag Week, the Phytophthora and Downy Mildew Workshop at Michigan Research and Extension Center, and the Midwest Cover Crop Council Meeting at Ada, OH. Technicians and graduate students were available to respond to growers with crop problems, and provide disease diagnosis and management. PARTICIPANTS: Principal Investigators: Jianjun Hao, Assistant Professor, PD Mary K. Hausbeck, Professor, Co-PD R. Michael Davis, Extension Specialist, Co-PI Rebecca Grumet, Professor, Co-PI Mathieu Ngouajio, Associate Professor, Co-PI Farm Advisor: Joe Nunez Technician: Drey Cark, James Counts, Brian Cortright, Aristarque Djoko, Sue Hammar, Sheila Linderman, Karina Perez, and Sue Hammar. Postdoctoral Research: Kaori Ando, Leah Granke, Lina Quesada-Ocampo, and Noah Rosenzweig. Graduate students: Marivi Colle, Tiffany Enzenbacher, Mike Meyer, Rachel Naegele, Prissana Wiriyajitsomboon. Rachel Naegele, and Prissana Wiriyajitsomboon. Student helper: Victoria Ackroyd, Nicole Bendt, Tara Gallagher, Damen Kurzer, Devin, Linderman, Ajay Nair, Andrew Worth, and Melissa VanOverbeke. Labor employees: Nicole Bendt, Alex Cook, Devin Linderman, Wesley Orr, and Andrew Worth. Visiting Scholar: Angela Vargas-Berdugo, Yang Bi, and He Jiang. TARGET AUDIENCES: Vegetable and cucurbit growers, carrots growers, pickle processors, cucurbit scientists, plant breeding and genomics scientists, industry leaders, extension educators, students, policy makers. All together our research and extension efforts reached over 18,000 people. PROJECT MODIFICATIONS: Not relevant to this project.

Impacts
1. Growers can use the cover crops to improve crop rotation systems with minimal risk of spreading the disease. Organic matter helps to increase microbial activity and disease suppression. Overall, there were brief periods when microbial activity was increased in the organic and transitional plots compared with the conventional farming systems. Rhizoctonia and Pythium species were significantly reduced by incorporating green manures in potato field. 2. Four pepper lines were resistant to P. capsici; none of the commercial cultivars was resistant to P. capsici isolate 12889. Of the 220 lines of peppers evaluated for root rot, CM334 is resistant to highly virulent isolates of P. capsici and three other lines of peppers are highly resistant to multiple isolates of P. capsici. Solanum habrochaites accession LA407 showed high tolerance to all P. capsici isolates tested. The resistance is distributed in several tomato lineages. In LA407 x Hunt100 population, 10 lines were resistant to P. capsici isolates OP97 and 12889, and 20 lines were resistant to only OP97. On the LA407 x Hunt100 population genetic map, twelve linkage groups correspond to the twelve tomato chromosomes. Four QTLs were identified. Greater similarity in overall gene expression was observed between peel samples at 8 and 16 dpp than between tissue types at a given age. Electron transport and plastid associated genes were most highly enriched in 8 dpp peel samples, while 16 dpp peel samples were more enriched for abiotic/biotic stimuli, stress, ER, golgi, hydrolase, and transferase related genes. One PI has shown reproducible resistance in three trials. This may be a valuable source for breeding. 3. Presidio is effective in controlling 1) P. capsici on squash, peppers and cucumbers when applied as a foliar spray and via drip irrigation; 2) P. asparagi on asparagus when applied as a crown soak and Pythium on carrot when applied as a drench. Products V-10208 and QGU42 were effective on all oomycete pathogens as foliar sprays, plant drenches, and drip irrigation applications. Favorable efficacy data was also generated for Zampro (ametoctradin + dimethomorph), Revus (mandipropamid), Ranman (cyazofamid), Gavel (zoxamide + mancozeb), Tanos (famoxadone + cymoxanil), Previcur Flex (propamocarb), Forum (dimethomorph), Acrobat (dimethomorph) and Reason (fenamidone). 4. Provide diagnostic/disease management assistance to growers. Knowledge of the factors conferring resistance and periods of greatest susceptibility can allow for better targeted disease control strategies and identification of traits associated with resistance. Growers were able to observe research in their own fields, tour research plots on research farms and other growers' farm and attend presentations on research on a yearly basis. Since irrigation water can remain infested or become reinfested annually with P. capsici for years after the adjacent fields are transitioned to nonsusceptible crops, growers are advised to avoid potentially infested irrigation water even after rotating to nonhost crops for several years.

Publications

  • Ackroyd J.V. and M. Ngouajio. 2011. Brassicaceae cover crops affect seed germination and seedling establishment in cucurbit crops. HortTechnology 21:525-532.
  • Grumet R, Colle M, Ando K, Xie DS, Havenga L, Switzenberg JA. 2012. Modified plant architecture to enhance crop disease control via reduced contact with soil borne pathogens: possible value of upright fruit position in cucumber. Eur J Plant Pathol. Doi.10.1007/s10658-012-0087-1.
  • Jiang, H. H., Meng, Q., Hanson, L. E., and Hao, J. J. 2012. First report of Streptomyces stelliscabiei causing potato common scab in Michigan. Plant Disease 96:904.
  • Meng, Q., Jiang, H., Hanson, L. E., and Hao, J. J. 2012. Characterizing a novel strain of Bacillus amyloliquefaciens BAC03 for potential biological control application. Journal of Applied Microbiology. (In press). DOI: 10.1094/PDIS-11-11-0932-RE.
  • Ando K, Carr KM, Grumet R. 2012. Transcriptome analysis of early cucumber fruit growth identifies distinct gene modules associated with phases of development. BMC Genomics. In press.
  • Crous, P.W., Summerell, B.A., Shivas, R.G., Burgess, T.I., Decock, C.A., Dreyer, L.L., Granke, L.L., Guest, D.I., Hardey, G.E.St.J., Hausbeck, M.K., Huberli, D., Jung, T., Koukol, O., Lennox, C.L., Liew, E.C.Y., Lombard, L., McTaggart, A.R., Pryke, J.S., Roets, F., Saude, C., Shuttleworth, L.A., Stukely, M.J.C., Vanky, K., Webster, B.J., Windstam, S.T., and Groenewald, J.Z. 2012. Phytophthora asparagi. Fungal Plant description sheets: 107-127. Persoonia 28:138-182.
  • Enzenbacher, T.B., and Hausbeck, M.K. 2011. Evaluation of fungicides for control of Phytophthora pod rot of lima bean, 2010. Plant Disease Management Reports 5:V121. Online.
  • Enzenbacher, T.B., and Hausbeck, M.K. 2012. An evaluation of cucurbits for susceptibility to cucurbitaceous and solanaceous Phytophthora capsici isolates. Plant Disease (in press).
  • Enzenbacher, T.B., and Hausbeck, M.K. 2012. Evaluation of fungicides for crop safety and control of Phytophthora pod rot of lima bean, 2011. Plant Disease Management Reports 6:V009. Online.
  • Granke, L., Quesada-Ocampo, L., Lamour, K., and Hausbeck, M. 2012. Advances in research on Phytophthora capsici on vegetable crops in the United States. Plant Disease (in press).
  • Granke, L.L., Quesada-Ocampo, L.M., and Hausbeck, M.K. 2011. Variation in phenotypic characteristics of Phytophthora capsici isolates from a worldwide collection. Plant Disease 95:1080-1088.
  • Granke, L.L., Quesada-Ocampo, L.M., and Hausbeck, M.K. 2012. Differences in virulence of Phytophthora capsici isolates from a worldwide collection on host fruits. European Journal of Plant Pathology 132:281-296.
  • Hausbeck, M.K., and Cortright, B.D. 2010. Managing cucumber diseases in the field. Pages 2-7 in: Pickling Cucumber Session Summaries, Great Lakes Fruit, Vegetable and Farm Market Expo, Grand Rapids, MI. Online.
  • Hausbeck, M.K., and Cortright, B.D. 2012. Evaluation of fungicides for control of Phytophthora and Pythium fruit rots of pickling cucumber, 2011. Plant Disease Management Reports 6:V135. Online.
  • Hausbeck, M.K., Granke, L.L., and Cortright, B.D. 2011. Asparagus disease update. Pages 2-4 in: Asparagus Session Summaries, Great Lakes Fruit, Vegetable and Farm Market Expo, Grand Rapids, MI. Online.
  • Morrice, J.J., and Hausbeck, M.K. 2011. Controlling cucumber diseases under extreme production conditions. Pages 5-9 in: Pickling Cucumber Session Summaries, Great Lakes Fruit, Vegetable and Farm Market Expo, Grand Rapids, MI. Online.
  • Granke, L.L., Quesada-Ocampo, L.M., and Hausbeck, M.K. 2011. Differences in virulence of Phytophthora capsici isolates from a worldwide collection on tomato fruits. Page 35 in Proceeding of the 26th Annual Tomato Disease Workshop, Cornell University, Ithaca, NY, Oct 11-13.
  • Ando, K., Colle, M., and Grumet, R. 2012. Transcriptional profiling of cucumber fruit peel. PAGXX. https://pag.confex.com/pag/xx/webprogram/Paper3072.html.
  • Enzenbacher, T. B. and Hausbeck, M. K. Using host susceptibility to manage Phytophthora rot of cucurbits, 3rd International Phytophthora capsici Meeting, Hawks Cay, Duck Key FL, Nov-Dec 2011. Poster presentation.
  • Granke, L. L., and Hausbeck, M. K. The effects of humidity, temperature, and wounding on development of Phytophthora rot of cucumber, Great Lakes Fruit, Vegetable and Farm Market Expo, Grand Rapids, Dec 2011. Poster presentation.
  • Granke, L. Quesada-Ocampo, and M. Hausbeck, Differences in virulence of Phytophthora capsici isolates from a worldwide collection, L. Pickle and Pepper Research Committee for MSU Meeting, E. Lansing, Jan 2011.
  • Granke, L., Quesada-Ocampo, L., Lebeis, A., Henderson, L., VanOverbeke, M., and Hausbeck, M. Global phenotypic variation in Phytophthora capsici, Annual Meeting of the American Phytopathological Society, Honolulu HI, Aug 2011. Poster presentation.
  • Granke, L., Quesada-Ocampo, L., Wood, M., Olsen, J., Mercier, M. and Hausbeck, M. Differences in virulence of Phytophthora capsici isolates from a global collection, Annual Meeting of the American Phytopathological Society, Honolulu HI, Aug 2011. Poster presentation.
  • Granke, L.L. and Hausbeck, M.K. Effects of temperature, humidity, and wounding on development of Phytophthora rot of cucumber fruit, 3rd International Phytophthora capsici Meeting, Hawks Cay, Duck Key FL, Nov-Dec 2011. Poster presentation.
  • Granke, L.L. and Hausbeck, M.K. Research updates on Phytophthora in Michigan, 2012 Phytophthora and Downy Mildew Workshop, Southwest Michigan Research and Extension Center, Benton Harbor, Feb 2012.
  • Naegele, R.P. and Hausbeck, M.K. Identification of phenotypic traits associated with pepper fruit host resistance to Phytophthora capsici, Great Lakes Fruit, Vegetable and Farm Market Expo, Grand Rapids, Dec 2011. Poster presentation.
  • Ngouajio M and D Clark. 2011. With Current Cover Crop Seeding Recommendations Achieving Appropriate Plant Populations is a Challenge With Small Seeded Species. Presentation at the Oceana County Summer Research Tour Sept 6, 2011.
  • Ngouajio M. 2011. Optimizing the performance of Brassica cover crops in annual and perennial vegetable systems. Great Lakes Fruits, Vegetable and Farm Market Expo, Grand Rapids MI. Dec 6-8, 2011
  • Ngouajio M. 2011. Brassica Cover Crops: Tools for Biofumigation and Soil Quality Improvement. Spring Horticulture Meeting, Hart, Michigan. March 15, 2011.
  • Ngouajio M. 2012. Feature Presentation: Improving productivity of onions grown on muck with mustard cover crops in Michigan. Empire State Fruit and Vegetable EXPO. Syracuse, New York, Jan 23-26, 2012.
  • Ngouajio M. 2012. Improving tomato, pepper, and eggplant rotation with cover crops: Experience from Michigan. Empire State Fruit and Vegetable EXPO. Syracuse, New York, Jan 23-26, 2012.
  • Ngouajio M. 2012. Practical ways to use cover crops as biofumigants. Midwest Cover Crop Council Annual Meeting, West Lafayette, Indiana, Feb., 29. 2012.
  • Ngouajio, M. 2011. Cover Crops as Biofumigants. Invited by Midwest Cover Crop Council (MCCC) to present at the Conservation Tillage and Technology Conference Feb 24-25, 2011.
  • Quesada-Ocampo, L., Granke, L., Mercier, M., Olsen, J., and Hausbeck, M. 2011. Investigating the genetic structure of Phytophthora capsici populations, Annual Meeting of the American Phytopathological Society, Honolulu HI, Aug 2011. Poster presentation.
  • Quesada-Ocampo, L.M. and Hausbeck, M.K. 2011. Investigating the genetic structure of Phytophthora capsici, 3rd International Phytophthora capsici Meeting, Hawks Cay, Duck Key FL, Nov-Dec 2011.
  • Ngouajio M. 2012. Stress Defenders: Acting as biofumigants, Brassica cover crops help reduce insects, weeds, and disease. American Vegetable Grower Magazine. May issue p. 16.
  • Quesada-Ocampo, L.M., Granke, L.L., and Hausbeck, M.K. 2011. Temporal genetic structure of Phytophthora capsici populations from a creek used for irrigation in Michigan. Plant Disease 95:1358-1369.
  • Quesada-Ocampo, L.M., Granke, L.L., Mercier, M.R., Olsen, J., and Hausbeck, M.K. 2011. Investigating the genetic structure of Phytophthora capsici populations. Phytopathology 101:1061-1073.
  • Granke, L., Quesada-Ocampo, L.M., Lebeis, A., Henderson, VanOverbeke, M., and Hausbeck, M. 2011. Global phenotypic variation in Phytophthora capsici. Phytopathology 101:S63.
  • Granke, L., Quesada-Ocampo, L.M., Wood, M., Olsen, J., Mercier, M., and Hausbeck, M. 2011. Differences in virulence of Phytophthora capsici isolates from a global collection. Phytopathology 101:S63.
  • Granke, L.L., and Hausbeck, M. K. 2010. The effects of temperature, humidity, and wounding on development of Phytophthora rot of cucumber. Phytopathology 100:S43.
  • Hao, J. J., Donis-Gonzalez, I. R., Jiang, H. H., and Fulbright, D. W. 2012. Antimicrobial activity in chestnut tissues corresponding with flavonol glycoside and terpenoid substances. The 5th International Chestnut Symposium. Shephedstown, WV. Nair A. and M. Ngouajio. 2011. Integrating Brassica Cover Crops Into Onion Cropping Systems: Implications for Plant Population, Stand Establishment, and Yield. HortScience 46:S203.
  • Quesada-Ocampo, L., Granke, L., Mercier, M., Olsen, J., and Hausbeck, M. 2011. Investigating the genetic structure of Phytophthora capsici populations. Phytopathology 101:S149.
  • Quesada-Ocampo, L., Granke, L., Olsen, J., Gutting, H., Runge, F., Thines, M., Lebeda, A., and Hausbeck, M. 2011. The genetic structure of Pseudoperonospora cubensis global populations. Phytopathology 101:S149.
  • Rodriguez-Salamanca, L., and Hausbeck, M. 2010. Asparagus as host of Phytophthora species prevalent in Michigan and its importance as a rotational crop. Phytopathology 100:S176.
  • Rosenzweig, N., Lu, X. H., Jiang, H., and Hao, J. 2012. Multigene analysis of Pythium species causing carrot cavity spot in California and Michigan. Phytopathology 102:S4.102.
  • Hausbeck, M.K. 2011. Carrot disease update. Pages 9-11 in: Carrot Session Summaries, Great Lakes Fruit, Vegetable and Farm Market Expo, Grand Rapids, MI. Online.
  • Hausbeck, M.K. 2011. Use integrated management strategies with Phytophthora on peppers. MSU Extension News for Agriculture: Vegetables Jul 29. Online.
  • Hausbeck, M.K. 2012. Carrot disease update. Carrot Country 20(2):6-8. Online.
  • Hausbeck, M.K., and Cortright, B.D. 2010. Asparagus disease research update. Pages 11-14 in: Asparagus Session Summaries, Great Lakes Fruit, Vegetable and Farm Market Expo, Grand Rapids, MI. Online.
  • Granke, L.L. Quesada-Ocampo, L.M. and Hausbeck, M.K. Differences in virulence of Phytophthora capsici isolates from a worldwide collection on host fruits, 3rd International Phytophthora capsici Meeting, Hawks Cay, Duck Key FL, Nov-Dec 2011.
  • Grumet R. Ando K. 2011. Rapidly expanding cucumber (Cucumis sativus) fruit show enriched expression of novel transcripts. PAG XIX http://www.intel-pag.or/19/abstracts/P01_PAGXIX_048.html.
  • Hao, J. J. 2012. Biological control agent BAC03 on controlling potato common scab. Nanjing Agricultural University, Nanjing, China, May 28.
  • Hao, J. J. 2012. Management of soilborne plant diseases. Beijing Plant Protection Station, Beijing, China, Jun. 5.
  • Hao, J. J. 2012. Microbial community in soil suppressive to potato common scab. Chinese Academy of Institution and Quarantine, Beijing, China, Jun. 5.
  • Hao, J. J. 2012. Soil microbial community analysis in soilborne disease management. Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, Beijing, China, Jun. 6.
  • Hao, J. J. 2012. Soil microbial community and soilborne diseases. China Agricultural University, Beijing, China, May 31.
  • Hao, J. J., Donis-Gonzalez, I. R., Jiang, H. H., and Fulbright, D. W. 2012. Antimicrobial activity in chestnut tissues corresponding with flavonol glycoside and terpenoid substances. The 5th International Chestnut Symposium. Shepherdstown, WV. Sep. 4 to 8.
  • Hausbeck, M. Carrot disease update, Carrot Session, Great Lakes Fruit, Vegetable and Farm Market Expo, Grand Rapids, Dec 2011.
  • Hausbeck, M. Comparing fungicides and application methods to reduce crown and root rot in cucumber and pepper, B. Cortright and M. Hausbeck, 3rd International Phytophthora capsici Meeting, Hawks Cay, Duck Key FL, Nov-Dec 2011.
  • Hausbeck, M. Understanding and managing Phytophthora diseases in fresh market vegetables: Vine crops, peppers, tomatoes, beans, Fruit and Vegetable Growers Association of Delaware Fresh Market Vegetables and Vine Crop Session, Delaware Agriculture Week, Delaware State Fairgrounds, Harrington, DE, Jan 2012.
  • Hausbeck, M. 2011. Understanding and managing Phytophthora diseases in processing vegetables: Pickles and beans, Fruit and Vegetable Growers Association of Delaware Processing Crops Session, Delaware Agriculture Week, Delaware State Fairgrounds.
  • Hausbeck, M. and Morrice, J. Controlling cucumber diseases under extreme production conditions, Pickling Cucumber Session, Great Lakes Fruit, Vegetable and Farm Market Expo, Grand Rapids, Dec 2011.
  • Hausbeck, M., Granke, L., and Cortright, B. Asparagus disease research and update, Asparagus Session, Great Lakes Fruit, Vegetable and Farm Market Expo, Grand Rapids, Dec 2011.
  • Hausbeck, M., Granke, L., and Cortright, B. Asparagus disease research and update, Asparagus Commodity Meeting, East Lansing, Feb 2012.
  • Naegele, R. P. and Hausbeck, M. K. Phenotypic and genotypic characterization of pepper fruit resistance to Phytophthora capsici, 3rd International Phytophthora capsici Meeting, Hawks Cay, Duck Key FL, Nov-Dec 2011. Poster presentation.


Progress 09/01/10 to 08/31/11

Outputs
OUTPUTS: 1. Greenhouse and field trials were conducted and brassica cover crops to test for their impact on Phytophthora blight. Twelve cover crops were inoculated with virulent strains of Phytophthora. The influence of conventional, organic, and transitional farming systems on potato and carrot production and disease development was studied. The influence of microbial activity and species diversity on damage caused by root knot nematodes and Pythium diseases were included. 2. Plant susceptibility to rot caused by P. capsici. Processing pumpkin (Cucurbita moschata) and winter squash (Cucurbita maxima) were studied in field research plots. Flowers were tagged at anthesis and hand pollinated. Fruits were harvested to determine soluble solid content. Fruits were inoculated with P. capsici isolate 12889 and incubated for 4 days. The susceptibility of cotyledons and fruit of pickling cucumber and yellow squash to P. capsici isolates was compared in a growth chamber. Greenhouse experiments evaluated resistance to root and fruit rot caused by two P. capsici isolates of 62 lines of a tomato inbred backcross population obtained from LA407 and Hunt100. LA407 x Hunt100 population genetic map was generated using 152 polymorphhic markers. The presence and position of quantitative trait loci (QTLs) was determined with permutation tests that establish the empirical significance thresholds of QTL mapping with the interval mapping LRS. After QTL location analysis, only chromosomes with significant QTLs detected were analyzed. To understand gene expression changes associated with the transition to resistance, 454 pyrosequencing analysis was performed on replicate cucumber fruit peel samples from 8 dpp (susceptible) and 16 ddp (resistant) greenhouse-grown fruit. These samples provided approximately 800,000 ESTs. All transcripts were mapped to the cucumber genome. BLAST analysis provided putative homologs for 95% of the contigs represented by >30 ESTs and was used to assign putative gene functions. Approximately half of the cucumber germplasm collection (687 PIs) was screened for resistance to P. capsici using an expedited protocol. Inoculated fruit were monitored daily for symptom severity using a rating scale of 1-5. 3. Twelve field trials with 191 treatment regimes tested the efficacy of products applied as foliar sprays, drenches and/or via drip irrigation for efficacy against P. capsici of cucurbits and pepper. Cucumber fruits are especially susceptible to rot caused by water molds; field trials compared 7-day calendar foliar sprays with sprays directed to the fruits. The genetic structure of 106 P. capsici isolates collected from a field (year 1) adjacent to a creek used for irrigation and from the creek itself (years 2,3,4) were evaluated using six polymorphic nuclear loci. 4. Field tours of the cover crop and the on-farm research plots were organized for growers, extension educators, industry leaders, and policy makers. Presentations were made at various meetings including: the West Central Spring Horticulture meeting in Hart, MI, the Fruit and Vegetable Grower Association of Delaware Ag Week, and the Midwest Cover Crop Council Meeting at Ada, OH. PARTICIPANTS: Principal Investigators: Jianjun Hao, Assistant Professor, PD Mary K. Hausbeck, Professor, Co-PD R. Michael Davis, Extension Specialist, Co-PI Rebecca Grumet, Professor, Co-PI Mathieu Ngouajio, Associate Professor, Co-PI Farm Advisor: Joe Nunez Technician: Drey Cark, James Counts, Brian Cortright, Aristarque Djoko, Sue Hammar, Sheila Linderman, Karina Perez, and Sue Hammar. Postdoctoral Research: Kaori Ando, Leah Granke, Lina Quesada-Ocampo, and Noah Rosenzweig, Graduate students: Marivi Colle, Tiffany Enzenbacher, Mike Meyer, Xiaohong Lu, Rachel Naegele, and Prissana Wiriyajitsomboon. Student helper: Victoria Ackroyd, Nicole Bendt, Tara Gallagher, Damen Kurzer, Devin Linderman, Ajay Nair, Andrew Worth, and Melissa VanOverbeke. Labor employees: Nicole Bendt, Alex Cook, Devin Linderman, Wesley Orr, and Andrew Worth. Visiting Scholar: Angela Vargas-Berdugo, Yang Bi, and He Jiang. TARGET AUDIENCES: Vegetable and cucurbit growers, carrots growers, pickle processors, cucurbit scientists, plant breeding and genomics scientists, industry leaders, extension educators, students, policy makers. All together our research and extension efforts reached over 5000 people. PROJECT MODIFICATIONS: Nothing significant to report during this reporting period.

Impacts
1. None of the cover crops tested was a viable host for P. capsici, which suggests the cover crops could be used by growers to improve crop rotation systems with minimal risk of spreading the disease. In disease suppressiveness created in the organic systems, there was a significant positive relationship between microbial activity and disease suppression and between levels of soil organic matter and disease suppression. Overall, there were brief periods when microbial activity was increased in the organic and transitional plots compared with the conventional farming systems. 2. In pumpkin and squash, younger fruits are more susceptible to P. capsici than older fruits. In tomato resistance screening, 10 of the lines were resistant to both isolates of P. capsici and 20 lines were resistant to only P. capsici OP 97. In the LA407 x Hunt100 population genetic map, 12 linkage groups were found that corresponded to the twelve tomato chromosomes. The map coverage achieved corresponds approximately to 81.4 percent of total genome for this advanced backcross type. Four QTLs were identified in tomato chromosomes 1, 2 and 3 to associate with P. capsici resistance. "Early Jalapeno" pepper is susceptible and "Criollo de Morelos" Mexican landrace is partially resistant to Phytophthora root, stem, crown rot and foliar blight. Significant differences are present between the pepper lines for resistance to P. capsici and P. nicotianae induced fruit rot. Fruit rot resistance to P. capsici and P. nicotianae does not appear to overlap between resistant lines. For cucurbits, all P. capsici isolates caused disease on both cotyledons and fruit of cucumber and squash but virulence varied. Cucurbit cotyledons exhibited a different susceptibility to P. capsici isolates than that observed in fruit. 3. Fungicides Presidio 4SC, Revus 2.08SC, Zampro 4.4 SC (initium + dimethomorph) and experimental products from DuPont and Valent controlled P. capsici on cucurbits and pepper. Forum and Ranman were also effective on cucurbits. Zampro prevented plant death when applied as 7-day drenches. The Valent experimental was effective when applied as a foliar spray, and as a drench. The DuPont experimental shows great promise for use as a foliar spray, drenches, and drench followed by drip applications. 4. Provide diagnostic/disease management assistance to growers. A technician and graduate students were available for diagnostic/disease management assistance. A high incidence and severity of bacterial blight on carrots was identified in northwest Michigan. At the request of growers, 17 diseased samples were processed. Knowledge of the factors conferring resistance and periods of greatest susceptibility can allow for better targeted disease control strategies and identification of traits associated with resistance. The sequencing results indicate that we can identify genes that are preferentially expressed in the peel tissue of resistant vs. susceptible fruit and provide a starting to point to identify changes corresponding with resistance to P. capsici. Screening of approximately half of the cucumber PI collection in 2011 identified a small number of PIs worthy of further testing.

Publications

  • Bi, Y., Cui, X., Lu X., Cai, M., Liu, X., and Hao, J. J. 2011. Baseline sensitivity of natural population and resistance of mutants in Phytophthora capsici to zoxamide. Phytopathology 101: 1104-1111.
  • Foster, J.M., and Hausbeck, M.K. 2010. Management of Phytophthora crown rot on peppers. Pages 109-112 in: Proceedings of the 2010 Mid-Atlantic Fruit and Vegetable Convention, Hershey PA, Feb 2-4.
  • Grumet R, Ando K. 2011. Rapidly expanding cucumber (Cucumis sativus) fruit show enriched expression of novel transcripts. PAG XIX. Http://www.intl-pag.org/19/abstracts/P01_PAGXIX_048.html (Abstract).
  • Grumet R. Pickling cucumber breeding for disease resistance. Great Lakes Fruit, Vegetable and Farm Market Expo, Grand Rapids, Dec 2010. Pages 8-10. Pickling Cucumber Session Summaries, Great Lakes Fruit, Vegetable and Farm Market Expo. Online.
  • Hausbeck, M. 2011. Look for Phytophthora disease on summer squash and zucchini now. MSU Extension News for Agriculture: Vegetable Jun 22. Online.
  • Hausbeck, M. 2011. Look for Phytophthora disease on winter squash and pumpkin now. MSU Extension News for Agriculture: Vegetable Jun 22. Online.
  • Hausbeck, M., Foster, J., and Linderman, S. 2010. Managing Phytophthora on winter squash. MSU Extension Vegetable Crop Advisory Team Alert 25:(Sep 8). Online.
  • Hausbeck, M.K., and Cortright, B.D. 2010. Asparagus disease research update. Pages 11-14 in: Asparagus Session Summaries, Great Lakes Fruit, Vegetable and Farm Market Expo. Online.
  • Hausbeck, M.K., and Cortright, B.D. 2010. Bacterial blight and other carrot diseases. Pages 2-6 in: Carrot Session Summaries, Great Lakes Fruit, Vegetable and Farm Market Expo. Online.
  • Hausbeck, M.K., and Cortright, B.D. 2010. Managing cucumber diseases in the field. Pages 2-7 in: Pickling Cucumber Session Summaries, Great Lakes Fruit, Vegetable and Farm Market Expo. Online.
  • Hausbeck, M.K., and Cortright, B.D. 2011. Bacterial blight and other carrot diseases. Carrot Country 19(1):4-8.
  • Lu, X. H., Davis, R. M., and Hao, J. J. 2011. Comparative study of Pythium species causing carrot cavity spot in California and Michigan. Phytopathology 101: S110.
  • Lu, X. H., Hausbeck, M. K., Liu, X. L., and Hao, J. J. 2011. Risk assessment of Phytophthora capsici resistant to fluopicolide. Phytopathology 101: S110.
  • Lu, X. H., Hausbeck, M. K., Liu, X. L., and Hao, J. J. 2011. Wild type sensitivity and mutation analysis for resistance risk to fluopicolide in Phytophthora capsici. Plant Disease 95: 1535-1541.
  • Lu, X. H., Livingston, S., Nunez, J. J., Davis, R. M., Hao, J. J. 2011. Pythium species associated with carrot cavity spot and their fungicide sensitivity in California and Michigan. Plant Disease. (In press).
  • Meyer, M.D., and Hausbeck, M.K. 2010. Staying ahead of Phytophthora crown rot and bacterial leafspot on pepper. Pages 2-5 in: Tomato/Pepper/Eggplant Session Summaries, Great Lakes Fruit, Vegetable and Farm Market Expo. Online.
  • Ngouajio M and N. Myers. 2011. Integrated management of asparagus following the end of the harvest period. Michigan State University Extension News for Agriculture; June 29, 2011. Available at URL: http://news.msue.msu.edu/news/article/integrated_management_of_aspara gus_following_the_end_of_the_harvest_period.
  • Ngouajio M., J.W. Counts, and D. Clark. 2011. Effect of compost and brassica cover crops on soil quality and asparagus performance. Abst. Book of Abstracts Intl. Symp. Organic Matter and Compost Use in Horticulture. 4-7 April, 2011, Adelaide, Australia. P55.


Progress 09/01/09 to 08/31/10

Outputs
OUTPUTS: 1. A nested-PCR method was developed to successfully detect several Pythium species responsible for causing cavity spot of carrots, and a real-time PCR method was validated to identify and quantify the population of Phytophthora capsici. These results have been distributed to growers' meeting, and other extension activities. 2. Brassica cover crops were tested for their impact on Phytophthora capsici incidence at a commercial farm in Michigan. Field tour of the research plot was arranged for growers, extension educators, industry leaders, and policy makers and a presentation was given on the project. Various presentations were made at the state, regional, national, and international levels. A field trial was conducted in California to compare the microbial community and its impact on plant diseases by comparing conventional, organic, and transitional soils. 3. We continued our efforts to identify changes in gene expression associated with the transition to resistance. We have obtained 454 pyrosequence data from fruit samples harvested at 0, 4, 8, 12, and 16 dpp. Study on pepper cultivars has concluded, published, and presented at meetings as noted elsewhere. Research comparing 42 tomato varieties and wild relatives for resistance/tolerance to P. capsici crown and root rot has concluded and was published and presented at meetings as noted elsewhere in this report. Greenhouse experiments were conducted to evaluate 65 lines of a tomato inbred backcross population obtained from LA407 and Hunt100 for resistance to root and fruit rot caused by two P. capsici isolates. Background studies were initiated to evaluate differences in susceptibility of cucurbit types and plant tissues. Squash has been studied for resistance to P. capsici, including fruit, variety, foliar blight associated with zoospore concentration and condition, and cucurbit foliage and fruit were compared. 4. Fifteen different vegetable trials have been conducted to test the efficacy of both fungicide (153 treatments) and fumigant products (5 treatments) for the control of Phytophthora capsici on pepper and yellow summer squash. Ten different fungicide products were tested for Pythium control on carrots using a greenhouse seedling drench study. Thirteen fungicide products were tested for efficacy on asparagus in the greenhouses using Phytophthora asparagi inoculums. 5. Five research plots were conducted with grower cooperators testing both fungicides and fumigants in commercial fields. Several new fields in the Oceana and Mason counties were confirmed to have P. capsici infestations. Local meetings, field and demonstration trials were arranged. A tour (Managing Phytophthora capsici on cucumbers, Pickle IPM Practices, 2010 EPA Decision Makers) was attended by 30 people from USDA and EPA. Phytophthora capsici isolates from irrigation water samples are being analyzed to determine whether isolates from within a source are genetically similar to each other. Thirty-three carrot, cucurbit, pepper and tomato samples from growers were processed, the pathogen(s) identified, and growers advised on handling the problem. This led to two major problems identified during field season 2010. PARTICIPANTS: Jianjun Hao, Assistant Professor, PD Mary K. Hausbeck, Professor, Co-PD R. Michael Davis, Extension Specialist, Co-PI Rebecca Grumet, Professor, Co-PI Mathieu Ngouajio, Associate Professor, Co-PI Joe Nunez, Farm Advisor Technician: Sue Hammar, James Counts, Karina Perez, Sheila Linderman, and Brian Cortright. Postdoctoral Research: Kaori Ando, and Sam Livingston Graduate students: Marivi Colle, Elizabeth Kelley, Xiaohong Lu, Tiffany Enzenbacher, Leah Granke, and Lina Quesada. Student helper: Ajay Nair, and Victoria Ackroyd, Tara Gallagher, Melissa VanOverbeke, Andrew Worth Labor employees Nicole Bendt, Devin Linderman, Wesley Orr TARGET AUDIENCES: Vegetable and cucurbit growers, carrots growers, pickle processors, cucurbit scientists, plant breeding and genomics scientists, industry leaders, extension personnel, students, policy makers. All together our research and extension efforts reached over 5000 people. PROJECT MODIFICATIONS: Nothing significant to report during this reporting period.

Impacts
1. The PCR protocols have been used for identification and quantification of pathogen in soil and plant tissues, which had benefits to the agricultural industry, and research on plant disease detection. 2. The brassica cover crops tested did not seem to represent a threat for the spread of Phytophthora capsici in vine crops fields. The cover crops and Sectagon application had limited effects on cucumber yield, but reduced soil microbial biomass and total soil microbial populations. The incorporation of green manures created a disease suppressive soil by elevating microbial activity, although inconsistency needs to be addressed in the future. A disease suppressive soil was developed by incorporating fresh organic matter. 3. Knowledge of the factors conferring resistance and periods of greatest susceptibility can allow for better targeted disease control strategies and for identification of traits associated with resistance. The sequencing results indicate that we can identify genes that are preferentially expressed in exponentially growing fruit and set a baseline for comparison to changes that may occur during the transition away from susceptibility to P. capsici. Incidence and severity of foliar blight were significantly affected by, and positively correlated with zoospore concentration of P. capsici; higher concentrations led to higher disease incidence and severity. Isolates of P. capsici varied in virulence. Early emerged leaves of cucumber, yellow squash, and green zucchini were more susceptible than leaves growing at later stage. Growers, industry stakeholders and other researchers were informed of research results of pepper and tomato studies comparing varieties for resistance/tolerance to P. capsici. In the study of cucurbits, significant differences were observed in disease response among fruits and significant differences in isolate virulence on these fruits. This suggests that in future germplasm screens of cucurbits for resistance to P. capsici, numerous isolates should be used to test fruit disease response. 4. Drench applications of fungicides are more effective than foliar application in controlling Phytophthora crown rot of squash. The newly registered fumigant Paladin (DMDS) was just as effective as methyl bromide/chloropicrin for controlling P. capsici in yellow squash and resulting in similar yields. Two new active ingredients including a product from Dupont and Valent have been established as priorities in the USDA IR-4 program. This ensures registration in the near future. Presidio SC and V-10208 SC were the only treatments to prevent plant death in the trial. Results of irrigation water sample analysis will help determine if single or multiple sources are responsible for contaminating irrigation water sources. All of the algaecides tested inhibited zoospore swimming. Several copper-based and one SPC-based algaecides showed efficacy similar to bleach. 5. Diseased carrots were identified as being infected with bacterial blight. A high incidence and severity of bacterial blight on carrots was identified in northwest Michigan.

Publications

  • Foster, J.M., and Hausbeck, M.K. 2010. Managing Phytophthora capsici in bell pepper using fungicides and host resistance. Plant Dis. 94:697-702.
  • Foster, J.M., and Hausbeck, M.K. 2010. Resistance of pepper to Phytophthora crown, root, and fruit rot is affected by isolate virulence. Plant Dis. 94:24-30.
  • Foster, J.M., Webster, B.J., and Hausbeck, M.K. 2010. Evaluation of fungicides for control of Phytophthora crown and root rot of zucchini, 2009. Plant Dis. Management Rep. No. 4:V044. Online.
  • Granke, L.L., and Hausbeck, M.K. 2010. Effects of temperature, concentration, age, and algaecides on Phytophthora capsici zoospore infectivity. Plant Dis. 94:54-60.
  • Grumet R. 2010. Transcriptome analysis of cucumber fruit development using next-generation sequencing technologies. HortSci. 45:S7. (Abstract).
  • Grumet, R., and Ando, K. 2010. Transcriptomic analysis of early fruit development in cucumber (Cucumis sativus). PAG XVIII http://www.intl-pag.org/18/abstracts/W25_PAGXVIII_184.html. (Abstract).
  • Hausbeck, M.K., Glaspie, S.L., and Linderman, S.D. 2010. Evaluation of fungicides for control of downy mildew, Phytophthora crown, fruit, and root rot, and Pythium fruit rot on cucumber, 2009. Plant Dis. Management Rep. No. 4:V101. Online.
  • Ngouajio, M. 2010. The potential of Brassica: A one-size-fits all approach will not work when using cover crops as biofumigants in vegetables. American vegetable Growers October: 35-36.
  • Ngouajio, M. and Counts, J.W. 2010. Biofumigation with Brassica cover crops in pickling cucumber and summer squash production systems. Pickling Cucumber Research Reporting Session Report 30-37. MSU, East Lansing.
  • Ngouajio, M. and Counts, J.W. 2010. Effects of Brassica cover crops on pickling cucumber and summer squash production in a site naturally infested with Phytophthora: Project Report 2009. Report submitted to The Michigan Vegetable Council. 8p.
  • Ngouajio, M., and Counts, J.W. 2009. Effect of biofumigation with Brassica cover crops on weed populations, soil microbial activity, and fruit rot in pickling cucumber production. Acta Horticulturae. (Submitted).
  • Ngouajio, M., Wang, G., and Goldy. R. 2010. Biofumigation with Brassica cover crops: Evaluation of performance in vegetable cropping systems. HortSci. 45:S75-76. (Abstract).
  • Quesada-Ocampo, L.M., and Hausbeck, M.K. 2010. Resistance in tomato and wild relatives to crown and root rot caused by Phytophthora capsici. Phytopathology 100:619-627.
  • Hao, J.J., Hausbeck, M.K., Ngouajio, M., Grumet R., and Davis, R.M. 2010. Detection and management of Phytophthora and Pythium in carrot, tomato, cucurbits, and asparagus. HortScience 45:S206. (Abstract).
  • Hao, J.J., Hausbeck, M.K, Bi, Y., and Kelley, E. 2010. Inhibitory effect of essential oils on Phytophthora capsici. Project Report 2010. Report submitted to The Michigan Vegetable Council. 4 p.
  • Lu, X.H., Zhu, S.S., Bi, Y., Liu, X.L., and Hao, J.J. 2010. Baseline sensitivity and resistance-risk assessment of Phytophthora capsici to iprovalicarb. Phytopathology 100:1162-1168.
  • Hausbeck, M., Foster, J., and Linderman, S. 2010. Managing Phytophthora on pepper. Michigan State University Extension Vegetable Crop Advisory Team Alert Newsletters 25:(Jul 1). Online.
  • Hausbeck, M.K., and Glaspie, S.L. 2010. Evaluation of fumigants for control of Phytophthora crown, fruit, and root rot of summer squash, 2009. Plant Dis. Management Rep. No. 4:V055. Online.
  • Hausbeck, M.K., and Rodriguez-Salamanca, L.M. 2009. Asparagus disease update. Great Lakes Fruit, Vegetable and Farm Market Expo, Asparagus Session Summaries. 2-4. Online.
  • Rodriguez-Salamanca, L., and Hausbeck, M. 2009. Asparagus as host of Phythophthora species prevalent in Michigan and its importance as rotational crop. Abstract. Caribbean Division Meeting of the American Phytopathological Society, Orlando, FL, 16-19 May.
  • Ando K., and Grumet R. 2010. Analysis of gene expression during early cucumber fruit development. ASPB P04058. (Abstract).
  • Ando K., and Grumet R. 2010. Transcriptional profiling of rapidly growing cucumber fruit by 454-pyrosequencing analysis. J Amer Soc Hortic Sci. 135:291-302.
  • Ando, K., and Grumet, R. 2009. Cucumber fruit transcriptome analysis by 454 sequencing. HortSci. 44:1126. (Abstract).
  • Enzenbacher, T.B., and Hausbeck, M.K. 2010. Isolates of Phytophthora capsici differ in their ability to cause disease on cucurbit fruits. Phytopathology 100:S34. (Abstract). Foster, J.M., and Hausbeck, M. 2010. Phytophthora research and control in peppers. Michigan State University Extension Vegetable Crop Advisory Team Alert Newsletters 25:(Aug 25). Online.
  • Foster, J.M., and Hausbeck, M.K. 2010. Evaluation of fungicide drenches and resistant cultivars for control of Phytophthora crown rot of pepper, 2009. Plant Dis. Management Rep. No. 4:V116. Online.
  • Foster, J.M., and Hausbeck, M.K. 2010. Evaluation of fungicides and resistant cultivars for control of Phytophthora crown rot of bell pepper, 2008, trial 2. Plant Dis. Management Rep. No. 4:V119. Online.
  • Foster, J.M., and Hausbeck, M.K. 2010. Evaluation of fungicides and resistant cultivars for control of Phytophthora crown rot of bell pepper, 2008, trial 1. Plant Dis. Management Rep. No. 4:V118. Online.


Progress 09/01/08 to 08/31/09

Outputs
OUTPUTS: Objective 1. Detection and quantification of Phytophthora and Pythium spp. I. A protocol of qPCR was developed for P. capsici in soil. II. A protocol of nested-PCR was developed for Pythium spp. detection in soil. III. The information was delivered to growers and other researchers at annual meeting of American Phytopathological Society, annual Carrot Symposium in Kern County, CA, the International Carrot Conference held in Anaheim, and in Carrot County. Objective 2: Cover crops and soil amendments. I. Field trials at a commercial farm with a history of Phytophthora. Brassica cover crops were tested for their impact on Phytophthora incidence. II. Field tour of the research plot. Growers, Extension educators, industry leaders, and policy makers toured the on-farm research plots and were given a presentation on the research being conducted. III. Various presentations were made at the state, regional and international levels. IV. We demonstrated that the incorporation of green manures provides a benefit for disease suppressive soil. Objective 3. Resistant/tolerant varieties I. We demonstrated that very young cucumber fruit are highly susceptible to infection by P capsici, but that susceptibility decreases as fruits develop and is, at least in part, associated with the fruit surface. II. We have characterized highly expressed genes during the phase of rapid cucumber fruit growth at 8dpp using ultra high-throughput 454 pyrosequencing analysis. III. The virulence of four Phytophthora capsici isolates from Michigan on pepper was determined. Resistance of crown and root rot was assessed following the inoculation of soilless media with P. capsici-infested millet seed. IV. Tomato varieties were examined for resistance to P. capsici, including fresh market and processing commercial cultivars, breeding lines, and 3 wild species. Objective 4. Fungicides. I. Zucchini Squash/P. capsici with mancozeb, Ridomil Gold MZ 76.5WP and Gavel 75DF. II. Acorn Squash with Ranman 3.6SC + Activator, Acrobat 50WP, and Revus 2.08SC + Activator 90. III. Carrot/Pythium ultimum with fungicides were applied as a drench to the pots prior to seeding. IV. Asparagus/P. asparagi with Presidio 4SC, Revus, Previcur Flex, Manzate, Tanos, Ranman, Bravo Weather Stik, Gavel, Reason 500SC, Ridomil Gold, Kocide 2000, Acrobat, Curzate, Pristine. Objective 5. Extension efforts. I. 2009 Decision Makers EPA Tour, Hart MI (33 attendees). II. Ten cucurbit and pepper samples from growers were processed, the pathogen identified, and growers advised on handling the problem. III. Brassica cover crops were tested for their impact on Phytophthora incidence. IV. Field tour of the research plot. Growers, Extension educators, industry leaders, and policy makers toured the on-farm research plots and attended the research presentation. V. Presentations were made at the state, regional and at international levels. VI. Annual Carrot Symposium in Kern County, CA. PARTICIPANTS: I. PI and co-PIs: Jianjun Hao, Mary Hausbeck, Rebecca Grumet, Mike Davis, Mathieu Ngouajio. II. Research technicians: James Counts, Karina Perez, and Sue Hammar. III. Undergraduate student helpers: Justin Hodgins, Ajay Nair, and Zach Werner. IV. Graduate students: Tiffany Enzenbacher, Leah Granke, Elizabeth Kelley, Xiaohong Lu, and Lina Quesada. V. Partner organizations: Pickle Packers International. VI. Postdoctoral researcher: Kaori Ando, Sam Livingston. TARGET AUDIENCES: Vegetable and cucurbit grower. Pickle processors. Cucurbit scientists. Extension educators. Industry leaders. Students. Policy makers. National Pickle Processors International Meeting 10/2009. All together our research and extension efforts reached over 3000 people PROJECT MODIFICATIONS: Nothing significant to report during this reporting period.

Impacts
Objective 1. Detection and quantification of Phytophthora and Pythium spp.. The use of our species-specific primers for the detection and quantification of Phytophthora capsici and Pythium spp. in soil is applicable to many agricultural systems. P. capsici and Pythium spp. cause diseases on multiple important crops in Michigan California. Knowing whether the pathogen exists in a field and if it is over the threshold needed for infection to occur, a proper crop can be planted to reduce the disease problem. The nested-PCR was species specific and can detect all four pathogenic these Pythium species in carrot tissue and in soil. Objective 2: Cover crops and soil amendments. The brassica cover crops tested did not seem to represent a threat for the spread of Phytophthora capsici in vine crops fields. The cover crops and Sectagon application had limited effects on cucumber yield. However, the nutrient cycling contribution of the cover crops was not taken into account in this study to adjust fertilizer applications. Disease suppressive soils can be developed by the incorporation of fresh organic matter and that pesticide use can be reduced. However, the window of time when the soils in the San Joaquin Valley are suppressive is quite limited since organic matter decomposes very quickly in the warm temperatures of the Valley. Objective 3. Resistant/tolerant varieties We can identify genes in cucumber that are preferentially expressed in exponentially growing fruit and set a baseline for comparison to changes that may occur during the transition away from susceptibility to P. capsici. Resistance is not due to failure to germination, however, there may be differences in signaling between the fruit surface and pathogen influencing appressorium formation and/or ability of the pathogen to enter the fruit. None of the commercial pepper cultivars were resistant to P. capsici isolate 12889, but several cultivars were resistant to the other isolates. The isolates varied in their ability to cause infection on the fruits of the different cultivars. Overall, pepper fruits were more susceptible to P. capsici than the roots and crowns. All P. capsici isolates tested incited disease in seedlings. Amplified fragment length polymorphisms of tomato varieties showed a lack of correlation between genetic clusters and susceptibility to P. capsici, indicating that resistance is distributed in several tomato lineages. Results of this study create a baseline for future development of tomato varieties resistant to P. capsici. Zucchini Squash/P. capsici: All treatments resulted in significantly fewer dead or wilted plants. Carrot/Pythium: Presidio SC, Revus SC, Ranman SC, Gavel DF, and Kocide 3000DF applications resulted in significantly more emerged seedling compared to the untreated inoculated packs for both rating dates. Objective 5. Extension efforts. The information has been delivered to growers and other researchers at the Carrot Symposium in Kern County, the International Carrot Conference, the annual meeting of the American Phytopathological Society, and in Carrot Country.

Publications

  • Livingston, S., and Davis, M. 2009. Monitoring microbial communities in vegetables grown in different management systems. Phytopathology 99:S76.
  • Lu, X. Zhu, S., Bi, Y. Hao, J. Liu, X. 2009, Characterization of spontaneous mutants of Phytophthora capsici resistant to iprovalicarb. Phytopathology 99:S77.
  • Journal Articles and Abstract Ando, K., and Grumet, R. 2009. Highly abundant cucumber (Cucumis sativus L.) fruit transcripts. Plant and Animal Genome Conf XVII. Http://www.intl-pag.org/17/absracts/P05r_PAGXVII_607.htm.
  • Ando, K., Hammar S., and Grumet, R. 2009. Age-related resistance of diverse cucurbit fruits to infection by Phytophthora capsici. J Amer Soc Hort Sci 134:176-182.
  • Foster, J., and Hausbeck, M. 2009. Phytophthora research and control in peppers. MSU Extension Vegetable Crop Advisory Team Alert Newsletters 24(16): (Aug 19). Online.
  • Foster, J.M., and Hausbeck, M.K. 2008. Phytophthora research and control in peppers. Great Lakes Fruit, Vegetable and Farm Market Expo, Tomato and Pepper Session Summaries, pp. 2-5. Online.
  • Foster, J.M., and Hausbeck, M.K. 2009. Evaluation of fungicides for control of Phytophthora blight of acorn squash, 2008. Pl. Dis. Manag. Reports 3:V088.
  • Ngouajio M. and Counts, J.W., 2009. Effect of biofumigation with Brassica cover crops on weed populations, soil microbial activity, and fruit rot in pickling cucumber production. 7th International symposium on chemical and non-chemical soil and substrate disinfestations SD 2009, P.79.
  • Ngouajio M. and J.W. Counts. 2009. Effect of biofumigation with Brassica cover crops on weed populations, soil microbial activity, and fruit rot in pickling cucumber production. Acta Horticulturae (Submitted).
  • Quesada-Ocampo, L.M., and Hausbeck, M.K. 2009. Resistance in tomato and wild relatives to Phytophthora capsici. Phytopathology 99:S106.
  • Proceedings Foster, J., and Hausbeck, M., 2008. Evaluating commercial and breeding lines of bell peppers for resistance to Phytophthora root, crown and fruit rot. Page 32 in: Proceedings of the 19th International Pepper Conference, Sep 7-10, Atlantic City, NJ.
  • Foster, J.M., and Hausbeck, M.K. 2009. Phytophthora research and control in peppers. The Tomato Magazine 13(1):19-21.
  • Hausbeck, M.K., and Cortright, B. 2008. New management techniques for Fusarium and Phytophthora control in asparagus production. Great Lakes Fruit, Vegetable and Farm Market Expo, Asparagus Session Summaries, pp. 6-8. Online.
  • Foster, J.M., and Hausbeck, M.K., 2009. Variety selection and fungicide programs for controlling Phytophthora in pepper. Pages 187-189 in: Proceedings of the 2009 Empire State Fruit and Vegetable Expo, Syracuse NY, Feb 11-12.
  • Hausbeck, M.K., 2009. Downy mildew and Phytophthora control in vine crops. Pages 193-195 in: Proceedings of the 2009 Empire State Fruit and Vegetable Expo, Syracuse NY, Feb 11-12.
  • Ngouajio M., 2009. Fitting biofumigant cover crops into your vegetable rotation. Proceedings the 2009 Empire State Fruit & Vegetable Expo and Becker Forum, Syracuse NY (Feb. 11-12, 2009). P124-127.
  • Other Publications Ando K., 2009. Evaluation of the role of plant architecture and cucumber fruit development in Phytophthora capsici disease development. Ph.D. Dissertation. Michigan State Univ.