Source: TENNESSEE STATE UNIVERSITY submitted to NRP
DEVELOPMENT OF SUSTAINABLE SOILBORNE DISEASE MANAGEMENT STRATEGIES FOR NURSERY PRODUCTION
Sponsoring Institution
National Institute of Food and Agriculture
Project Status
COMPLETE
Funding Source
EVANS-ALLEN
Reporting Frequency
Annual
Accession No.
1017806
Grant No.
(N/A)
Cumulative Award Amt.
(N/A)
Proposal No.
(N/A)
Multistate No.
(N/A)
Project Start Date
Oct 1, 2018
Project End Date
Sep 30, 2021
Grant Year
(N/A)
Program Code
[(N/A)]- (N/A)
Recipient Organization
TENNESSEE STATE UNIVERSITY
3500 JOHN A. MERRITT BLVD
NASHVILLE,TN 37209
Performing Department
Agricultural and Environmental Sciences
Non Technical Summary
Nursery crops are produced with annual sale value of $5.1 billion in the United States. Nursery crops in Tennessee account for asignificant portion of agricultural production with $132 million in sales annually (USDA, 2014).Soilborne pathogens often survive for long periods on host plant debris, soil organic matter, or as free-living organisms.As an example, losses due to soilborne diseases in Georgia in 2014 were estimated to be $149 million in ornamental and turf production (Little, 2014). Due to the large number of plant species produced in the nursery industry, soilborne disease management research is challenging.Nursery producers and university representatives at the Southern Region Nursery Crop Pest Management Meeting rated root rot as the most important disease in nursery production(IPM, 2009).In addition, based on nursery inspections and disease samples received in the Ornamental Plant Pathology Lab at the Tennessee State University Nursery Research Center (TSUNRC), we have documented that soilborne pathogens are the most economically important pathogens.These diseases reduced plant growth, increased costs to the nursery grower and caused potential ecological damage to the natural environment.The National Integrated Pest Management (IPM) Road Map has listed "Develop advanced management tactics for specific settings that prevent or avoid pest/disease attack" and efforts to "Improve the efficiency of suppression tactics and demonstrate least-cost options and pest/disease management alternatives" as critical research needs (IPM, 2013). Soilborne diseases are becoming more difficult to manage because of increased pathogen resistance and restrictions of the use of some chemicals. Conventionally, soilborne diseases are controlled by using soil fumigants, in-furrow fungicides, or fungicide seed treatment. Once a widely used fumigant, methyl bromide, was phased out of use in 2005 due to its negative effect on the stratospheric ozone layer (Dungan et al., 2003). The loss of methyl bromide has promoted increased interest in alternative methods to control soilborne diseases.Although environmentally friendly chemical and non-chemical plant disease management methods have been developed, their results are still inconsistent and less effective than the previous standard, methyl bromide (Gerik and Hanson, 2011). Locally, large- and small-scale nursery producers have asked we develop and validate effective alternative soilborne disease management strategies to improve woody ornamentals productivity and profitability under particular environmental conditions. Several producers have participated in the development of this proposal by group discussion at the TSUNRC.The loss of methyl bromide has promoted increased interest in alternative environmental friendly methods to control soilborne diseases.The integration of biofumigation, chemical and biorational products solely, or in combination, will provide more successful and sustainable solutions for improving soil quality and enhancing natural soilborne disease control in field grown production and propagation systems of woody ornamentals. Therefore, we propose to encourage the adoption of proven uses of biofumigation, chemical and biorational products by documenting their effects in field grown nursery production and propogation systems. We emphasize that the development of a multiple systems approach to improve soilborne disease management and soil quality using biofumigation, chemical and biorational products will help improve the productivity, profitability and sustainability of field grown nursery production and propagation of woody ornamentals.The long-term goal of the proposed project is to improve production efficiency and reduce soilborne disease pressure through economic and effective applications of biofumigation, chemical and biorational products on field grown ornamental nurseries. Biofumigation, chemical and biorational products will be evaluated in field grown nursery production systems and their effects on plants, microbial communities, and soilborne diseases will be documented. In order to provide effective and sustainable recommendations to nursery producers with a useful synthesis of our results, the following objectives will be pursued: 1)assess environmentally friendly biofumigantsin combination with solarizationfor soilborne diseases and improved plant growth; 2) assessthe efficacy of chemical and biorational products for controlling soilborne diseases with different application methods, intervals and reduced-rate applications in woody ornamentals; and 3) engage in outreach and technology transfer with field nursery producers.
Animal Health Component
50%
Research Effort Categories
Basic
30%
Applied
50%
Developmental
20%
Classification

Knowledge Area (KA)Subject of Investigation (SOI)Field of Science (FOS)Percent
2122110104030%
2162499116070%
Knowledge Area
212 - Pathogens and Nematodes Affecting Plants; 216 - Integrated Pest Management Systems;

Subject Of Investigation
2110 - Ornamental trees and shrubs; 2499 - Plant research, general;

Field Of Science
1040 - Molecular biology; 1160 - Pathology;
Goals / Objectives
Our proposed project will directly reduce soilborne diseases and improve productivity in the nursery industry through research and outreach. Improved sustainable disease management strategies will significantly reduce the risk of soilborne disease epidemic development in the field. It is our goal to identify effective soilborne disease management strategies for field nursery production of woody ornamentals to manage soilborne pathogens that can be easily and readily adopted by Tennessee field nursery producers.Assess environmentally friendly biofumigantsin combination with solarizationfor soilborne diseases and improved plant growth.Impact: Provide the woody ornamental nursery industry with an environmentally friendly disease management strategy that suppresses soilborne disease population densities comparable to chemical products.Assess the efficacy of chemical and biorational products for controlling soilborne diseases with different application methods, intervals and reduced-rate applications in woody ornamentals.Impact: Provide the woody ornamental nursery industry with efficacious, cost-effective and sustainable recommendations for soilborne disease management.Engage in outreach and technology transfer with field nursery producers.Impact: We will be able to provide significant outputs to the woody ornamental nursery industry, researchers, extension specialists and agents on the effectiveness of different application methods, intervals and reduced fungicides rates, efficacy of soilborne disease management strategies such as biofumigants for reducing soilborne pathogen populations. This will lead to outcomes of nursery producers changing their behavior to include more sustainable production practices and reduction in the amount of fungicides applied in field-grown nurseries of woody ornamental.
Project Methods
The following work will be conducted primarily at the Tennessee State University, Otis Floyd Nursery Research Center in McMinnville, TN. The work in Objective 1 will be conducted also on-site at a nursery (Schaeffer Nursery-propagation-field ground bed system)in Middle Tennessee.Objective 1.Assess environmentally friendly biofumigantsin combination with solarizationfor soilborne diseases and improved plant growth.At the TSUNRC, ground beds will be artificially inoculated withPhytophthora nicotianaeorRhizoctonia solanibased on established protocol (Benson and Tjosvold, 2008 and Liyanapathiranage, 2017). Infested/non-biofumigated non-covered, non-infested/non-biofumigated non-covered plots will be used as controls. Treatments will bewhite mustard, purple top forage turnips, astro arugula, mighty mustard, dwarf essex rape, amara mustard, oriental mustard, biofumigant DOMINUS (allylisothiocyanate)(at 170 and 340 lb/A) and only solarization. Biofumigant cover crops will be seededinto 8.0 x 2.5 m beds with a seed rate provided by manufacturer in April. Flowering biofumigant plants will be dug from randomly chosen 0.25 m2areas in each plot to determine plant biomass volumes. Flowering biofumigants will be rototilled 15-cm deep into the soil.After incorporation, plotswill be covered with polyethylene film for 30 days.Biofumigant DOMINUS (at 170 and 340 lb/A) will be applied in dedicated plots same day, and those plots will be covered withpolyethylene film for 30 days as well. Before and after application of biofumigant cover crops or DOMINUS, population density of the pathogen(s) and fluorescentPseudononadswill be determined using selective media. Temperature and soil moisture in the plots will be monitored using WatchDog. After the 30-day period, viburnum or boxwood plants will be transplanted into the plots infested withRhizoctoniaorPhytophthora, respectively. Assays will be run for 3 months. Disease occurrence and incidence will be evaluated throughout the trial. Plants will be evaluated for root rot severity using a 1-5 ordinal scale where 1 = healthy, 2 = 25% or less roots necrotic, 3 = 26 - 50% roots necrotic, 4 = more than 50% roots necrotic, and 5= plant dead. Fresh weight and plant height will be recorded at the end of the trial. Soil tests will be performed to determine levels of macro and micro-nutrients, soil pH and organic matter. TSUNRC field experiment will be conducted in two seasons to validate repeatability of the treatments.At Schaefer Nursery, based on the outcome of TSUNRC first year field trial a subset of biofumigant cover crops, a rate of biofumigant DOMINUS and only solarizationwill be evaluated in field trial. On-farm trial will be set up in prevalent soilborne pathogen pressure. Non-biofumigated non-covered plots will be used as control. Assays will be run as described before. Viburnum and boxwood plants will be evaluated for root rot severity as described before.Soil samples will also be taken and analyzed for soilborne pathogensbefore and after application of biofumigant cover crops or DOMINUSto determine any reduction in populations.Statistical analyses will be performed in SAS statistical software. Analyses of variance will be conducted on the data estimates of disease severity, measures of plant health and pathogen abundance using mixed model or nonparametric Kruskal-Wallis test. Means comparison will be performed using Fisher's LSD test.Objective 2.Assess the efficacy of chemical and biorational products for controlling soilborne diseases with different application methods, intervals and reduced-rate applications in woody ornamentals.Objective 2a.Fungicides [including, but not limited to Segovis (oxathiapiprolin)Empress (pyraclostrobin), Pageant (pyraclostrobin + boscalid), and biorational products [such as, but not limited to, Rootshield (Trichoderma harzianum), Rhapsody (Bacillus subtilis), Regalia (Reynoutria sachalinensis) and Thymol] will be evaluated for ability to control soilborne diseases (R. solaniandP. nicotianae) under greenhouse conditions. The experiment will be established at the TSUNRC as a randomized complete block design with four replications. 4 in. pots containing sterilized soil will be artificially inoculated with each pathogen. Treatments will be applied per label requirements and fallowed by different application methods (dip, spray or drench), intervals (7, 14 or 21 days) and reduced rate. Boxwood and viburnum cuttings will be propagated in fall and disease occurrence and incidence will be evaluated throughout the trial. Area Under the Disease Progress Curves (AUDPC) will be calculated using the formula AUDPC = ∑[(Xi+1 + Xi)/2](ti+1-ti). Cuttings will be evaluated for root development and disease severity on root at the end of the trial using 1-5 ordinal scale: 1 = no symptom, heavily branched root system, and healthy looking; 2 = light brown necrosis in distinct spots, often necrosis in the root tip, less branched root system than healthy roots; 3 = few side roots, and dark brown necrosis in distinct spots; 4 = few and small side-roots, and dark brown necrosis of most of the root system, or all around the stem; 5 = plant dead. Fresh weight will be recorded at the end of the trial.Statistical analyses of treatment data will be conducted using established methods (the generalized linear mixed models procedure with SAS statistical software).Objective 2b.Based on greenhouse experiment outcomes the PI will select a subset of treatments to be evaluated at field conditions. The experiment will be set up atthe TSUNRC as a randomized complete block design with four replications. Field assessments of disease incidence and severity will be measured as described before.Objective 3.Engage in outreach and technology transfer with woody ornamental nursery producers.We will conduct workshops, training sessions/demonstration field days for nursery producers on buofumigation, chemical and biological control in Years 2 and 3 (at the TSUNRC auditorium, demonstration plots and on farm. Questionnaires will be presented to participants following each activity session to identify the impact of the activity and suggestions for changes which will be used to revise activity for the next session. Three months after the each activity, a general assessment will be delivered to participants to determine their decision-making in adoption of techniques on their farms. Prior to the activities, hand-outs and visual guide/posters (2 products) related to the activity topics will be produced and given to participants and to those unable to attend the workshops.Our outreach efforts will also include dissemination of information to the nursery industry through local crop management and nursery conferences as well as national conferences, meetings, written materials (eXtension publications, fact sheets, Extension articles and technical bulletins, journal papers), video clips (uploaded to TSU Extension YouTube channel), social media,TSUNRC andTSU Cooperative Extension Program websites and TSUNRC LISTSERV.

Progress 10/01/18 to 09/30/21

Outputs
Target Audience:Graduate assistantship:Two M.S. level and 3 PhD level (Advisor) and one M.S. level (co-Advisor) students participated into this project. The students involved in protocol development, experimental design, conducting experiments, data collections for the projects. Extension/Outreach:As woody ornamental plant pathologist, interacted directly with nursery producer, TSU extension agents and TDA regulatory officials toprovide diagnoses of biotic and abiotic problems and management recommendations to support sustainable nursery production in Tennessee. Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided? Nothing Reported How have the results been disseminated to communities of interest?Woody ornamental plant pathology lab interacted directly with nursery producer, TSU extension agents and TDA regulatory officials to provide diagnoses of biotic and abiotic diseases and management recommendations to support sustainable nursery production in Tennessee. Our lab diagnosed over 250 woody ornamental samples in spring 2021. Woody ornamental plant pathology lab also participated in the training of nursery growers on soilborne diseases and their management. What do you plan to do during the next reporting period to accomplish the goals? Nothing Reported

Impacts
What was accomplished under these goals? Evaluate the efficacy of chemical and biorational products for controlling soil-borne diseases with different application methods, intervals and reduced-rate applications in ornamentals.? The purpose of this study was to evaluate fire ant venom alkaloids and an alarm pheromone analog against several plant pathogens, includingBotrytis cinerea,Fusarium oxysporum,Phytophthora nicotianae, P. cryptogea,Pseudomonas syringae,Phytopythium citrinum,Rhizoctonia solani,Sclerotonia rolfsii,Xanthomonas axonopodis, andX. campestris. All pathogens were tested against red imported fire ant venom alkaloid extract and alarm pheromone compound for growth inhibition in in vitro assay. The venom alkaloid extract inhibited fungal and oomycete pathogens. Neither of the treatments were effective against bacterial pathogens. Three soilborne pathogens,P. nicotianae,R. solani,F. oxysporum, and one foliar pathogen,B. cinereawere selected for further in-vivo assays on impatiens (Impatiens walleriana'Super Elfin XP violet'). Total plant and root weight were higher in venom alkaloid treated plants compared to an inoculated control. The venom alkaloid treatment reduced damping-off, root rot severity, and pathogen recovery in soilborne pathogen inoculated plants. Similarly, venom alkaloid reduced Botrytis blight. However, higher venom rates caused foliar phytotoxicity on plants. Therefore, additional work is needed to evaluate rates of venom alkaloids or formulations to eliminate negative impacts on plants. Overall, these results suggest that red imported fire ant venom alkaloids may provide a basis for new products to control soilborne and foliar plant pathogens. Develop improved soil-borne disease management strategies based on cultural approaches for suppression of Rhizoctonia and (or) Phytophthora spp. and other soil-borne pathogens. We studied the response of the major cover crops being used by woody ornamental growers in the Southeastern United States toPhytopythium vexans, Phytophthora nicotianae, andRhizoctonia solaniin greenhouse conditions to identify the effective cover crops that can be used in a nursery field production system. Data related to post-emergence damping-off and plant growth parameters (plant height increase and fresh weight) were recorded. Similarly, cover crop roots were assessed for root rot disease severity using a scale of 0-100% roots affected. Among the tested cover crops, the grass cover crops triticale (×Triticosecale Wittm. ex A. Camus.), annual ryegrass (Lolium multiflorumL.), Japanese millet (Echinochloa esculenta(A. Braun) H. Scholz), and the legumes Austrian winter pea (Pisum sativumvar. arvense (L.) Poir) and cowpea 'Iron and Clay' (Vigna unguiculata(L.) Walp.), showed lower root rot disease severity and post-emergence damping-off in the soil inoculated withP. nicotianae, R. solani, orP. vexanscompared to the other crops. Since these cover crops can act as non-host crops and benefit the main crop in one way or another, they can be used in the production system.

Publications

  • Type: Journal Articles Status: Published Year Published: 2021 Citation: Panth, M., Witcher, A., and Baysal-Gurel, F. 2021. Response of cover crops to Phytopythium vexans, Phytophthora nicotianae, and Rhizoctonia solani, major soilborne pathogens of woody ornamentals. Agriculture 11(8):742 DOI: 10.3390/agriculture11080742
  • Type: Journal Articles Status: Published Year Published: 2021 Citation: Yang, X., Castroagudin, V.L., Daughtrey, M., Loyd, A., Weiland, J.E., Shishkoff, N., Baysal-Gurel, F., Santamaria, L., Salgado-Salazar, C., LaMOndia, J.A., Crouch, J., Luster. D.G. 2021. A Diagnostic guide for Volutella blight affecting Buxaceae. Plant Health Progress. https://doi.org/10.1094/PHP-02-21-0052-DG.
  • Type: Journal Articles Status: Published Year Published: 2021 Citation: Bika, R. and Baysal-Gurel, F. 2021. Identification of Fusarium commune, the causal agent of postharvest zinnia meltdown disease in Tennessee. HortTechnology. https://doi.org/10.21273/HORTTECH04795-21
  • Type: Journal Articles Status: Published Year Published: 2021 Citation: Dawadi, S., Baysal-Gurel, F., Addesso K.M., Liyanapathiranage, P., and Simmons, T. 2021. Fire ant venom alkaloids: Possible control measure for soilborne and foliar plant pathogens. Pathogens. 2021, 10, 659. https://doi.org/10.3390/pathogens10060659
  • Type: Journal Articles Status: Published Year Published: 2021 Citation: Bika, R., Copes, W., Baysal-Gurel, F. 2021. Comparative Performance of Sanitizers in Managing Plant-to-plant Transfer and Postharvest Infection of Calonectria pseudonaviculata and Pseudonectria foliicola on Boxwood. Plant Disease. DOI: 10.1094/PDIS-03-21-0481-RE.
  • Type: Journal Articles Status: Published Year Published: 2021 Citation: Bika, R., Palmer, C., Alexander, L., and Baysal-Gurel, F. 2020. Comparative performance of reduced-risk fungicides and biorational products in management of post-harvest Botrytis cinerea on hydrangea cut flowers. HortTechnology. https://doi.org/10.21273/HORTTECH04656-20.
  • Type: Other Status: Published Year Published: 2021 Citation: Baysal-Gurel, F., Bika, R., Simmons, T, and Jennings, C. 2021. Evaluation of fungicides for the control of Volutella blight of boxwood, 2020. Plant Disease Management Report No. 15:OT001. Online publication. The American Phytopathological Society, St. Paul, MN.
  • Type: Other Status: Published Year Published: 2021 Citation: Baysal-Gurel, F., Simmons, T, and Jennings, C. 2021. Evaluation of fungicides for the control of boxwood blight, 2020. Plant Disease Management Report No. 15:OT002. Online publication. The American Phytopathological Society, St. Paul, MN.
  • Type: Other Status: Published Year Published: 2021 Citation: Baysal-Gurel, F., Parajuli, M., and Panth, M. 2021. Evaluation of fungicides, biofungicides, host plant defense inducers and fertilizer for the control of Phytopythium root rot of red maple, 2020. Plant Disease Management Report No. 15:OT014. Online publication. The American Phytopathological Society, St. Paul, MN.
  • Type: Journal Articles Status: Published Year Published: 2021 Citation: Baysal-Gurel, F., Bika, R., Avin, F.A., Jennings, C., and Simmons, T., 2021. Occurrence of Volutella Blight Caused by Pseudonectria foliicola on Boxwood in Tennessee. Plant Disease. https://doi.org/10.1094/PDIS-01-21-0109-PDN
  • Type: Journal Articles Status: Published Year Published: 2021 Citation: Baysal-Gurel, F., Bika, R., Jennings, C., Palmer, C., and Simmons, T. 2020. Comparative performance of chemical and biologically-based products in management of algal leaf spot on magnolia. HortTechnology. https://doi.org/10.21273/HORTTECH04692-20.
  • Type: Other Status: Published Year Published: 2021 Citation: Baysal-Gurel, F., Parajuli, M., and Panth, M. 2021. Evaluation of fungicides, biofungicides, host plant defense inducers and fertilizer for the control of Phytopythium root rot of ginkgo, 2020. Plant Disease Management Report No. 15:OT017. Online publication. The American Phytopathological Society, St. Paul, MN.
  • Type: Other Status: Published Year Published: 2021 Citation: Baysal-Gurel, F., Neupane, S., and Simmons, T. 2021. Evaluation of fungicides, biofungicides, host plant inducers and fertilizer for the control of Phytophthora root rot of boxwood in field conditions, 2020. Plant Disease Management Report No. 15:OT018. Online publication. The American Phytopathological Society, St. Paul, MN.
  • Type: Other Status: Published Year Published: 2021 Citation: Baysal-Gurel, F., and Neupane, K. 2021. Evaluation of fungicides and host plant defense inducers for the control of Phytophthora root rot of dogwood, 2020. Plant Disease Management Report No. 15:OT019. Online publication. The American Phytopathological Society, St. Paul, MN.
  • Type: Other Status: Published Year Published: 2021 Citation: Baysal-Gurel, F. 2021. Phytophthora Root Rot Control on Field-Grown Boxwood. Chase Digest August 2021 Issue Volume 9(8).
  • Type: Other Status: Published Year Published: 2021 Citation: Neupane, K. and Baysal-Gurel, F. 2021. Fungicides for Phytophthora Root Rot in Containerized Dogwood. Chase Digest June 2021 Issue Volume 9(6).
  • Type: Other Status: Published Year Published: 2021 Citation: Bika, R. and Baysal-Gurel, F. 2021. Comparative Performance of Sanitizers in Managing Boxwood Blight and Volutella Blight BBIG Newsletter Volume 2, Issue 2, released May 28, 2021 and also at https://irp.cdn-website.com/217658e5/files/uploaded/BBIG%20Newsletter%20Vol%202%20Issue%202.pdf
  • Type: Other Status: Published Year Published: 2021 Citation: Baysal-Gurel, F. 2021. Control of Fusarium Root Rot on Oakleaf Hydrangea. Chase Digest May 2021 Issue Volume 9(5).
  • Type: Other Status: Published Year Published: 2021 Citation: Parajuli, M., Baysal-Gurel, F., Avin, F., and Panth, M. 2021. Phytopythium Root Rot Prevention on Maple. Chase Digest April 2021 Issue Volume 9(4).
  • Type: Other Status: Published Year Published: 2021 Citation: Baysal-Gurel, F. 2021. Control of Phytophthora Root Rot on Field-grown Boxwood with Fungicides and Biologicals. Chase Digest April 2021 Issue Volume 9(4).
  • Type: Other Status: Published Year Published: 2021 Citation: Panth, M., Baysal-Gurel, F., Avin, F., and Simmons, T. 2021. Phytopythium Root Rot Prevention on Gingko. Chase Digest February 2021 Issue Volume 9(2).
  • Type: Conference Papers and Presentations Status: Published Year Published: 2021 Citation: Neupane, S., Alexander, L., Baysal-Gurel, F. 2021. Response of Hydrangea quercifolia cultivars to Fusarium root and crown rot. 2021 ASHS Annual Meeting. Denver, CO. August 5-9, 2021 (Poster presentation).
  • Type: Conference Papers and Presentations Status: Published Year Published: 2021 Citation: Ghimire, B., Avin, F., and Baysal-Gurel, F. 2021. Development of loop-mediated isothermal amplification method for detection of Phytopythium vexans in different sources. The 43th Annual University-Wide Research Virtual Symposium, 2021. March 22-26, 2021 (Poster presentation).
  • Type: Conference Papers and Presentations Status: Published Year Published: 2021 Citation: Ghimire, B., Avin, F. A., Waliullah, S., Ali, Md E., Baysal-Gurel, F. 2021. Detection of Phytopythium vexans in different sources using loop-mediated isothermal amplification. Annual Meeting of the American Phytopathological Society  Plant Health 2021 online. August 2-6, 2021 (Poster presentation) (complimentary registration award from APS Foundation ($269)).
  • Type: Conference Papers and Presentations Status: Published Year Published: 2021 Citation: Neupane, K. and Baysal-Gurel, F. 2021. Management of Phytophthora cinnamomi using fungicides and host plant defense inducers under drought conditions. Annual Meeting of the American Phytopathological Society  Plant Health 2021 online. August 2-6, 2021 (Poster presentation) (complimentary registration award from Bayer ($269)).
  • Type: Conference Papers and Presentations Status: Published Year Published: 2021 Citation: Parajuli, M., Panth, M. and Baysal-Gurel, F. 2021. Effect of solitary and combined use of cover crops on soilborne disease suppressiveness in woody ornamental nursery production systems. Plant Health 2021 online. August 2-6, 2021 (Poster presentation).
  • Type: Conference Papers and Presentations Status: Published Year Published: 2021 Citation: Bika, R. and Baysal-Gurel, F. 2021. Dip application of sanitizers in managing postharvest infection of Calonectria pseudonaviculata on boxwood cuttings. Annual Meeting of the American Phytopathological Society  Plant Health 2021 online. August 2-6, 2021 (Poster presentation).
  • Type: Conference Papers and Presentations Status: Published Year Published: 2021 Citation: Neupane, S. and Baysal-Gurel, F. 2021. Performance of fungicides, biofungicides, fertilizers, and host plant defense inducers in managing Phytophthora root rot of boxwood in greenhouse. Annual Meeting of the American Phytopathological Society  Plant Health 2021 online. August 2-6, 2021 (Poster presentation).
  • Type: Conference Papers and Presentations Status: Published Year Published: 2021 Citation: Bika, R., Avin, F., and Baysal-Gurel, F. 2021. Postharvest disease caused by Fusarium commune: A new threat to zinnia cut flower production. The 43th Annual University-Wide Research Virtual Symposium, 2021. March 22-26, 2021 (Oral presentation).
  • Type: Conference Papers and Presentations Status: Published Year Published: 2021 Citation: Neupane, S., Simmons, T., and Baysal-Gurel, F. 2021. Management of Phytophthora root rot of boxwood using fungicides, biofungicides, fertilizers and host plant defense inducers in field conditions. The 43th Annual University-Wide Research Virtual Symposium, 2021. March 22-26, 2021 (Oral presentation).
  • Type: Conference Papers and Presentations Status: Published Year Published: 2021 Citation: Parajuli, M., Panth, M., and Baysal-Gurel, F. 2021. Cover crop usage for the sustainable management of soilborne diseases in woody ornamental nursery production system. The 43th Annual University-Wide Research Virtual Symposium, 2021. March 22-26, 2021 (Oral presentation).
  • Type: Conference Papers and Presentations Status: Published Year Published: 2021 Citation: Parajuli, M., Panth, M., and Baysal-Gurel, F. 2021. Efficacy of fungicides and biofungicides in controlling root and crown rot disease of woody ornamental plants caused by Phytopythium vexans. The 43th Annual University-Wide Research Virtual Symposium, 2021. March 22-26, 2021 (Poster presentation).
  • Type: Conference Papers and Presentations Status: Published Year Published: 2021 Citation: Neupane, K., and Baysal-Gurel, F. 2021. Efficacy of fungicides and biofungicides to manage Phytophthora cinnamomi under drought condition. The 43th Annual University-Wide Research Virtual Symposium, 2021. March 22-26, 2021 (Oral presentation).
  • Type: Other Status: Published Year Published: 2021 Citation: Panth, M., Witcher, A., and Baysal-Gurel, F. 2021. Response of different cover crops against Phytophthora nicotianae. 98th Southern division APS virtual meeting. Feb 15-19, 2021 (Poster presentation).
  • Type: Conference Papers and Presentations Status: Published Year Published: 2021 Citation: Parajuli, M., Panth, M., and Baysal-Gurel, F. 2021. Cover crop usage for the sustainable management of soilborne diseases in woody ornamental nursery production system. 98th Southern division APS virtual meeting. Feb 15-19, 2021 (Poster presentation).
  • Type: Conference Papers and Presentations Status: Published Year Published: 2021 Citation: Neupane, S., and Baysal-Gurel, F. 2021. Evaluation of chemical and biocontrol products for the management of Fusarium root and crown rot of oakleaf hydrangea. 98th Southern division APS virtual meeting. Feb 15-19, 2021 (Southern division APS meeting scholarship award and second place- Southern division APS meeting Poster competition).
  • Type: Conference Papers and Presentations Status: Published Year Published: 2021 Citation: Neupane, K., and Baysal-Gurel, F. 2021. Efficacy of fungicides, biofungicides, host plant defense inducers and fertilizer to manage Phytophthora root rot of dogwood under flooding condition. 98th Southern division APS virtual meeting. Feb 15-19, 2021 (Southern division APS meeting scholarship award) (Oral presentation).
  • Type: Conference Papers and Presentations Status: Published Year Published: 2021 Citation: Bika, R. and Baysal-Gurel, F. 2021. Comparative Performance of Sanitizers in Reducing the Plant-to-plant Transfer of Calonectria pseudonaviculata in Boxwood Using Cutting Tool. Northeastern plant, pest, and soil conference. Jan 4-7, 2021 (Graduate student travel award).


Progress 10/01/19 to 09/30/20

Outputs
Target Audience:Graduate assistantship:Four M.S. level and 1 PhD level (Advisor) and two M.S. level (co-Advisor) students participated into this project. The students involved in protocol development, determining inoculation methods, experimental design, conducting experiments, data collections for the projects. Extension/Outreach:As woody ornamental plant pathologist, I interacted directly with nursery producer, TSU extension agents and TDA regulatory officials toprovide diagnoses of biotic and abiotic problems and management recommendations to support sustainable nursery production in Tennessee. Changes/Problems:Due to Covid 19, we had limited outreach activities in Summer and Fall 2020. What opportunities for training and professional development has the project provided? Nothing Reported How have the results been disseminated to communities of interest?Woody ornamental plant pathology lab interacted directly with nursery producer, TSU extension agents and TDA regulatory officials to provide diagnoses of biotic and abiotic diseases and management recommendations to support sustainable nursery production in Tennessee. Our lab diagnosed over 200 woody ornamental samples in fall 2020. Woody ornamental plant pathology lab also participated in the training of nursery growers on soilborne diseases and their management. What do you plan to do during the next reporting period to accomplish the goals?1. Evaluate the efficacy of chemical and biorational products for controlling soil-borne diseases with different application methods, intervals and reduced-rate applications in woody ornamentals. We will continueto evaluate chemicals and biorational products for use in soil-borne disease management at greenhouse and field conditions. 2.Develop improved soil-borne disease management strategies based on cultural approaches for suppression of soil-borne pathogens. We will continue to evaluate cultural approaches for use in soil-borne disease managementaton-farms and on-station. 3.Characterize the associations between microbial community profile and soil-borne disease suppression expressed in different soil-borne disease management strategies.Microbial community analyses will be performed on field experiment root and soil samples.

Impacts
What was accomplished under these goals? Evaluate the efficacy of chemical and biorational products for controlling soil-borne diseases with different application methods, intervals and reduced-rate applications in ornamentals.? Soilborne diseases caused by pathogens such asPhytophthora,Rhizoctonia,Fusarium,Verticillium, andPythiumspecies are the most important diseases of woody ornamentals. Gingko (Gingko biloba) and red maple (Acer rubrumL.) 'October Glory' plants grown in containers and fields in Tennessee have shown root and crown rot symptoms with dark brown to black lesions in 2017 and 2018.The objective of this research was to isolate and identify pathogens affecting gingko and red maple plants in nurseries of Tennessee and develop fungicide/biofungicide management recommendations for nursery producers.Isolations were made from the infected roots. SeveralPhytophthora-like colonies with spherical zoospores, filamentous to globose oogoni, and whitish mycelium, were isolated on V8-PARPH medium. For confirming identity,total genomic DNA was extracted followed by thesequence analysis of the internal transcribed spacer (ITS) regions, andlarge subunit (LSU) of the nuclear ribosomal RNA (rRNA) as well ascytochrome c oxidase subunit I (Cox I) and cytochrome c oxidase subunit II (Cox II) of mitochondrial DNA (mtDNA). Based on morphological and molecular analysis,Phytopythium vexanswas described as a causal agent of crown and root rot from the infected gingko and red maple plants. To complete Koch's postulates, a pathogenicity test was performed by drenching 100 ml V8 agar medium slurry ofP. vexansinoculum on 1-year-old potted ginkgo plant root systems as well as red maple 'October Glory'. Necrotic lesion development was observed in the root system 45 days after inoculation andP. vexanswas re-isolated from the roots of both gingko and red maple. All control gingko and red maple plants remained disease-free and no pathogen was re-isolated. In addition, the efficacy of fungicides, biofungicides, fertilizer and host-plant defense inducers (traditionally recommended for management of oomycete diseases) for control of Phytopythium crown and root rot was evaluated on gingko and red maple 'October Glory' seedlings in greenhouse and field trials. In both greenhouse and field trials, the fungicides such as Empress Intrinsic, Pageant Intrinsic, Segovis andSubdue MAXXwere effective, and biofungicide such as Stargus was promising to reduce the disease severity caused by pathogenP. vexanson gingko and red maple plants. This comparative study will help nursery producers to make proper management decisions for newly reported Phytopythium crown and root rot disease of gingko and red maple plants. Characterize the associations between microbial community profile and soil-borne disease suppression expressed in different soil-borne disease management strategies. Phytophthora nicotianaeis a soilborne plant pathogen which can infect 255 genera in 90 families and is one of the most devastating soilborne pathogens in the south-eastern United States. This pathogen can affect a diverse group of plants, including woody ornamentals, causing wilting and chlorosis of leaves, stem and crown necrosis, while below ground symptoms comprise root necrosis. The objective of this research experiment was to evaluate the impact of cover crops on the soilborne diseases in field nursery production. Winter cover crops (triticale or crimson clover) were seeded at the manufacturer recommended rates in September - October (optimal timing for each cover crop species) in 2.4 x 14.6 m field plots with four replicates per treatment at Pleasant cove nursery, Rock Island, TN USA (Warren Co.). Plots were prepared by disk harrow and cover crop seeds broadcast, followed by a cultipacker to incorporate seed into the soil. Plots with no cover crop (bare soil) were used as control. A preemergent herbicide(Sureguard (Valent BioSciences LLC.,Libertyville,IL USA))was applied post-transplant within tree rows to prevent weed/cover crop competition at the base of the trees. Each plot was sampled randomly at four locations each within rows and within middles, mixed in situ with a spade, and placed in a plastic bucket. The soil was stored for one week, at an ambient temperature in a greenhouse before use. The greenhouse bioassays were conducted at the Tennessee State University Otis L. Floyd Nursery Research Center (TSUNRC) in McMinnville, TN, USA. The soil sample from each field treatment -1) cover crop- triticale, 2) cover crop- crimson clover, and 3) bare soil (control); and replication was divided into round plastic containers (top diameter-16 cm, bottom diameter-13.5 cm and height-16 cm) with 3 kg of soil per container. Those soils were then used as either inoculated (withP. nicotianae, the rice grain method [6]) or non-inoculated. Isolate FBG201507 ofP. nicotianaewas obtained from the culture collection of Dr. Fulya Baysal-Gurel at the TSUNRC. For each bioassay, ten single-pot replications per treatment were arranged in a randomized complete block design. Rooted cuttings of red maple were transplanted into the containerized field soil, and disease severity was assessed 2 months later. Drip irrigation system was used once per day for 1 min during the experiment. The severity of root rot was assessed using a scale of 0-100% at the end of the experiment.Plant width and height were recorded at the beginning and end of the experiment to be able to calculate the difference. Total plant fresh weight and root weight were recorded at the end of the experiment. The presence ofPhytophthorawas confirmed by plating root samples on PARPH-V8 selective medium. Disease severity, pathogen recovery, total plant weight, root weight and increase in plant height were analyzed with a one-way analysis of variance (ANOVA) using Proc GLM in SAS, and means were separated using Tukey test (α=0.05). In the greenhouse bioassay without the addition of pathogen inoculum,Phytophthoradisease severity was significantly lower in soil collected from the cover crop treatments compared to the bare soil treatment. But there were no significant differences between triticale and crimson clover cover crops in disease severity. The pathogen recovery was significantly lower in triticale cover crop treatment compared to the bare soil treatment. There were no significant differences between crimson clover cover crop treatment and the bare soil treatment in pathogen recovery. There were no significant differences between the cover crop treatment and the bare soil treatment in total plant weight and height increase with no pathogen inoculum introduction. In the greenhouse bioassay with the addition ofP. nicotianaeinoculum,Phytophthoraroot rot severity and pathogen recovery was significantly lower in soil collected from the cover crop treatments compared to the bare soil treatment. Disease severity was lower in triticale cover crop treatment compared to crimson clover cover crop treatment. There were no significant differences between triticale cover crop treatment and crimson clover cover crop treatment inPhytophthorapathogen recovery. Total plant weight was significantly greater in the cover crop used soil compared to the bare soil. Increase in maple plant height was significantly greater when the crimson clover cover crop was used compared to the bare soil. Overall, the cover crops were effective in reducingPhytophthorapressure in maple production system, however, longer period of cover cropping might be required to see the prolonged effect of cover crops. Growers can get benefit of incorporating these cover crops into production by reducing the need for synthetic crop protection materials.

Publications

  • Type: Journal Articles Status: Published Year Published: 2020 Citation: Panth, M., Hassler, S., and Baysal-Gurel, F. 2020. Methods for management of soilborne diseases in crop production. Agriculture. (Baysal-Gurel-corresponding author). Agriculture 10(1), 16; https://doi.org/10.3390/agriculture10010016
  • Type: Journal Articles Status: Published Year Published: 2020 Citation: Tekin, N.T., Kaplanoglu, E., Erdemir, E., Baysal-Gurel, F., Uyanik, C., and Hargrove, S. K. 2020. Modeling and Testing of Magnetic Speed Controlled Submersible Robot for Hydroponic Production. 2019 SoutheastCon. IEEE pp. 1-4. DOI:10.1109/SoutheastCon42311.2019.9020356.
  • Type: Conference Papers and Presentations Status: Published Year Published: 2020 Citation: Ojha, V., Oliver, J., Addesso, K., Baysal-Gurel, F., Youssef, N., and Simmons, T. 2020. Optimization of Phytophthora effective systemic fungicides for ambrosia beetle management. SNA Research Conference Vol; 64 2020. Entomology section.
  • Type: Conference Papers and Presentations Status: Published Year Published: 2020 Citation: Neupane, S., Simmons, T., and Baysal-Gurel, F. 2020. Management of Phytophthora root and crown rot using biofumigation on field grown boxwood. SNA Research Conference Vol; 64 2020. Pathology and Nematology Section.
  • Type: Conference Papers and Presentations Status: Published Year Published: 2020 Citation: Panth, M. and Baysal-Gurel, F. 2020. Impact of cover crop usage on soilborne disease suppressiveness in field nursery production. SNA Research Conference Vol; 64 2020. Pathology and Nematology Section.
  • Type: Conference Papers and Presentations Status: Published Year Published: 2020 Citation: Baysal-Gurel, F. Brown, M.S., Oliver, J., Addesso, K. 2019. Evaluation of fungicides and biofungicide to control Phytophthora root rot and ambrosia beetles on flood-stressed flowering dogwoods. Ambrosia beetle working group meeting proceeding. October 15, 2019. Griffin, GA.
  • Type: Journal Articles Status: Published Year Published: 2020 Citation: Baysal-Gurel, F., Liyanapathiranage, P., Panth, M., Avin, F.A., and Simmons, T. 2020. First report of Phytopythium vexans causing root and crown rot on flowering cherry in Tennessee. Plant Disease. https://doi.org/10.1094/PDIS-06-20-1166-PDN
  • Type: Journal Articles Status: Published Year Published: 2020 Citation: Panth, M., Baysal-Gurel, F., Simmons, T., Addesso, K., and Witcher, A. 2020. Impact of winter cover crop usage in soilborne disease suppressiveness in woody ornamental production system. Agronomy 10(7), 995; https://doi.org/10.3390/agronomy10070995
  • Type: Journal Articles Status: Published Year Published: 2020 Citation: Hudson, O., Walilullah, S. Hand, J. Gazis-Seregina, R., Baysal-Gurel, F., and Ali, E. 2020. Novel method for detection of Phytophthora capsici in irrigation water using loop-mediated isothermal amplification. J. Vis. Exp., e61478, doi:10.3791/61478.
  • Type: Other Status: Published Year Published: 2020 Citation: Baysal-Gurel, F. 2020. Phytophthora root and crown rot of boxwood. Tennessee Greentimes. Volume 21/No. 1 Spring 2020.
  • Type: Other Status: Published Year Published: 2020 Citation: Baysal-Gurel, F. 2019. Control of Phytophthora on boxwood. Chase Digest August 2019 Issue Volume 7(8).


Progress 10/01/18 to 09/30/19

Outputs
Target Audience:Graduate assistantship:Three M.S. level (Advisor) and two M.S. level (co-Advisor) students participated into this project. 2 M.S. students successfully completed their proposal defenses in December 2018 and 2 M.S. students (co-advisor) successfully completed their proposal defenses in February and March 2019. The students involved in protocol development, determining inoculation methods, experimental design, conducting experiments, data collections for the projects. Extension/Outreach:As woody ornamental plant pathologist, I interacted directly with nursery producer, TSU extension agents and TDA regulatory officials toprovide diagnoses of biotic and abiotic problems and management recommendations to support sustainable nursery production in Tennessee.We diagnosed 210 plant, water and soil samples in 2018. The TSU Nursery Research Center woody ornamental pathology lab confirmedthree new diseases in Tennessee in 2018:Phoma leaf spot on orchid and Zonate leaf spot on Cardinus. inOur lab also confirmed boxwood blight in Summer 2018 at sales yard inSmithnville, TN.I worked closely withnursery producer, TSU extension agents and TDA regulatory officials, providing recommendations regarding this important disease and its management. Lead researcherattended to seven national meetings/conferences, oneInternational Congress in Turkey, one International Conference in Florida,three extension activities, and thirty-one extension trainings (includingMaster Gardener Class, TDA inspectors training and Job Shadow)during this period.Lead researcherorganized one seminar and invited Dr. Brian McSpadden Gardener as a seminar speaker on at TSUNRC Conference room in McMinnville, TN. The title of his seminar was "Getting the Most from Composts- Nutrients, Humates, and Microbes, and More for Nursery Professionals".Growers, master gardeners, undergraduate and graduate level students, researchers and the general public attended to this educational event. Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided? Nothing Reported How have the results been disseminated to communities of interest?Woody ornamental plant pathology lab interacted directly with nursery producer, TSU extension agents and TDA regulatory officials to provide diagnoses of biotic and abiotic diseases and management recommendations to support sustainable nursery production in Tennessee. Our lab diagnosed over 200 woody ornamental samples in 2018. Woody ornamental plant pathology lab also participated in the training of nursery growers on soilborne diseases and their management. What do you plan to do during the next reporting period to accomplish the goals?1. Evaluate the efficacy of chemical and biorational products for controlling soil-borne diseases with different application methods, intervals and reduced-rate applications in woody ornamentals. We will continueto evaluate chemicals and biorational products for use in soil-borne disease management at greenhouse and field conditions. 2.Develop improved soil-borne disease management strategies based on cultural approaches-biofumigant cover cropsfor suppression of soil-borne pathogens. We will continue to evaluate cultural approaches for use in soil-borne disease managementaton-farms and on-station. 3.Characterize the associations between microbial community profile and soil-borne disease suppression expressed in different soil-borne disease management strategies.Microbial community analyses will be performed on field experiment root and soil samples.

Impacts
What was accomplished under these goals? Evaluate the efficacy of chemical and biorational products for controlling soil-borne diseases with different application methods, intervals and reduced-rate applications in ornamentals.Boxwood 'Green Velvet' cuttings were taken from the mother plants at commercial nursery in Smithville, TN. Cuttings were 4-inch in height and three leaves were kept remaining. A slant cut was made at the end of the stem and from the remaining leaves; half of the leaves were cut and removed. Cuttings were dipped in 1% 3-Indole Butyric Acid(IBA) (Harmodin®3, OHP Inc, Mainland, PA) and the cuttings were stacked with wet clothes until transplant. Boxwood cuttings were planted in 2-inch nursery containers on 7 Nov, 2018.The 2-inch nursery containers contain Morton's Pine Bark Nursery Mix were inoculated withP. nicotianaegrown on rice grains for 10 days. Two rice grains were placed 1-inches below the surface potting mix on 31 Oct, 2018. Non-treated, non-inoculated and non-treated, inoculated containers served as controls. Twenty single-boxwood cuttings per treatment were arranged in a completely randomized design in a greenhouse at the Otis L. Floyd Nursery Research Center in McMinnville, TN. Boxwood cuttings were watered with overhead irrigation system one time per day for 1 minute. The standard treatment included only Subdue Maxx drench application at 10 weeks interval, and the rotation program included Pageant spray at transplanting, Pageant spray 2 weeks after first application, Chipco 26019 spray application 3 weeks after second Pageant spray application, and Empress drench application 3 weeks after Chipco 26019 spray application. Spray applications of fungicides was applied to run-off using a backpack CO2-pressurized sprayer at 40 psi. The boxwood cuttings were re-potted from 2-inches to 4-inches nursery containers in Morton's Pine Bark Nursery Mix on 28 Nov, 2018 and from 4-inches to 1 gal nursery containers on 9 Jan, 2019. Five plants were pulled and cleaned on 28 Nov 2018, 9 Jan, 6 Feb and 6 Mar 2019 for assessment of root development using 1-5 scale where 1 is unrooted cutting not callused, no roots developed; 2 is callus with root bumps; callus with first true root; 3 is at least 3 -5 roots ¼ -½" in length; 4 is 5-7 or more roots at least 1" in length; 5 is fully rooted liner and assessment of Phytophthora root rot severity using a scale of 0-100% roots affected. Plant height, total fresh weight and root weight were also recorded on 6 Mar and plant marketability was evaluated using a scale of 1-5 where 1 is dead, 3 is commercially acceptable and 5 is a perfect plant. Phytophthora root rot disease pressure was high in this trial with non-treated, inoculated control rooted boxwood cuttings showing 53.0% disease severity by 6 Mar. Fungicide rotation program (Pageant Intrinsic, Chipco 26019 and Empress Intrinsic) and Subdue Maxx alone significantly reduced Phytophthora root rot severity compared to non-treated, inoculated control. Phytophthora root rot severity was numerically higher in Subdue Maxx treated rooted boxwood cuttings compared to fungicide rotation program. Fungicide rotation program and Subdue Maxx significantly increased the plant height, total fresh weight and root weight compared to non-treated, inoculated control. The rotation program resulted numeric increase on the percent plant height compared to Subdue Maxx; but resulted significant increase on the percent plant height compared to non- treated, inoculated and non-inoculated controls. Phytotoxicity and defoliation were not observed in any of the rooted boxwood cuttings. Non-treated, inoculated control rooted boxwood cuttings were not commercially acceptable due to the level of Phytophthora root rot at the end of the experiment (data not shown). Bare root boxwood 'Green Velvet' plants were potted in no. 1 nursery containers in Morton's no. 2 Grow Mix on 3 Oct.Eight single-plant replications per treatment were arranged in a completely randomized design in a greenhouse at the Otis L. Floyd Nursery Research Center in McMinnville, TN. Each plant was top dressed with 5 g of 18-6-8 Nutricotecontrolled-releasefertilizeron 5 Oct. Boxwood plants were watered with overhead irrigation system two times per day for 2 minutes.Plants were inoculated withP. nicotianaegrownon rice grains for 10 days. Four rice grains were placed 2 in below the surface potting soil on 26 Oct.Non-treated, non-inoculated and inoculated containers served as controls.Spray applications of Orkestra Intrinsic were applied to run-off using a backpack CO2-pressurized sprayer at 40 psi beginning on a 14-day schedule. Empress Intrinsic, Orvego, Segovis and Subdue Maxx were applied as drench application on a 14-day schedule. Defoliation due to disease was assessed by using a scale of 0-100% on 16 and 30 Nov; and 15 Dec. On 14 Dec, total fresh weight, root weight and root length were recorded and severity of Phytophthora root rot was assessed using a scale of 0-100% roots affected. All fungicide treatments significantly reduced disease severity and the defoliation percentage due to Phytophthora root rot compared to non-treated, inoculated control boxwood plants, but there were no differences among treatments on the defoliation percentage. Empress Intrinsic and Orvego program, Orvego and Orkestra Intrinsic program, and Segovis and Subdue Maxx program and Empress Intrinsic alone most effectively reduced Phytophthora root rot disease severity. Total fresh weight was significantly different among Empress Intrinsic and Orvego program, Orvego and Orkestra Intrinsic program, and Segovis and Subdue Maxx program, Empress Intrinsic alone, Orkestra Intrinsic alone treated and Orvego alone treated, non-treated, inoculated control boxwood plants. Plants treated with Empress Intrinsic and Orvego program and Orvego and Orkestra Intrinsic program had the highest and statistically similar root weight values. The root length was significantly different among treated and non-treated, inoculated control boxwood plants. Phytotoxicity was not observed in any of the treated boxwood plants. Characterize the associations between microbial community profile and soil-borne disease suppression expressed in different soil-borne disease management strategies.Soilborne diseases are the most economically important problem of Southern region nursery producers. The goal of this research was to improve Rhizoctonia root rot disease management through the use of soil solarization alone and in combination with biofumigant cover crops- arugula 'Astro' (Eruca vesicariassp.sativa), mustard green 'Amara' (Brassica carinata) and turnip 'Purple top forage' (B. rapa); good quality compost and mustard meal amendment. The experiments were established as on-farm trials with prevalentRhizoctonia solanipopulation in propagation beds. All three biofumigant cover crops, arugula 'Astro', mustard green 'Amara' and turnip 'Purple top forage' in combination with solarization were able to reduce the Rhizoctonia root rot in flowering cherry 'Kwanzan' plants in nursery propagation beds. Compost amendment numerically or significantly increased the flowering cherry rooted cuttings growth (plant weight, root weight and plant height) compared to other treatments. Soil solarization in combination with cover crops and organic inputs could be used as part of an integrated approach to manage Rhizoctonia root rot in nursery crop propagation beds.

Publications

  • Type: Journal Articles Status: Published Year Published: 2019 Citation: Baysal-Gurel, F., Liyanapathiranage, P. 2019. Pathogenicity of Rhizoctonia solani and Phytophthora nicotianae to Brassicaceae cover crops. Archives of Phytopathology and Plant Protection. DOI: 10.1080/03235408.2019.1617499
  • Type: Journal Articles Status: Published Year Published: 2019 Citation: Brown, M., Baysal-Gurel, F., Oliver, J., and Addesso, K. 2019. Comparative performance of fungicides, biofungicides, and host plant defense inducers in suppression of Phytophthora root rot in flowering dogwood during simulated root flooding events. Plant Disease. First look https://doi.org/10.1094/PDIS-09-18-1597-RE.
  • Type: Journal Articles Status: Published Year Published: 2019 Citation: Baysal-Gurel, F., and Simmons, T. 2019. Evaluation of fungicides for the control of powdery mildew of Hydrangea, 2018. Plant Disease Management Report. Online publication. The American Phytopathological Society, St. Paul, MN.
  • Type: Journal Articles Status: Published Year Published: 2019 Citation: Baysal-Gurel, F., and Simmons, T. 2019. Evaluation of fungicides for control of Cercospora leaf spot on Hydrangea, 2018. Plant Disease Management Report. Online publication. The American Phytopathological Society, St. Paul, MN.
  • Type: Journal Articles Status: Published Year Published: 2019 Citation: Baysal-Gurel, F., and Simmons, T. 2019. Evaluation of fungicides for the control of black spot of rose, 2018. Plant Disease Management Report. Online publication. The American Phytopathological Society, St. Paul, MN.
  • Type: Conference Papers and Presentations Status: Published Year Published: 2019 Citation: Baysal-Gurel, F., and Simmons, T. 2019. Management of Cercospora Leaf Spot of Hydrangea with Fungicides and Biorational Products. SNA Research Conference Vol. 63 2019. Pathology and Nematology Section.
  • Type: Conference Papers and Presentations Status: Accepted Year Published: 2019 Citation: Baysal-Gurel, F., and Simmons, T. 2019. Evaluation of Fungicide Rotations at Different Application Intervals for the Control of Powdery Mildew of Dogwood. SNA Research Conference Vol. 63 2019. Pathology and Nematology Section.
  • Type: Conference Papers and Presentations Status: Other Year Published: 2019 Citation: Baysal-Gurel, F. 2019. Track and Trace: Plant Pathogen Detection. 1st International Molecular Plant Protection Congress. April 10-13, 2019. Adana, Turkey.
  • Type: Conference Papers and Presentations Status: Other Year Published: 2019 Citation: Holden, M., Simmons, T., Baysal-Gurel, F. 2019. Occurrence of Fusarium Crown Rot on Oakleaf Hydrangea (Hydrangea quercifolia). The 41th Annual University-Wide Research Symposium, 2019. April 1-5, 2019. Nashville, TN.
  • Type: Conference Papers and Presentations Status: Other Year Published: 2019 Citation: Panth, M. Simmons, T., Baysal-Gurel, F. 2019. Occurrence of Phytopythium disease on woody ornamentals. The 41th Annual University-Wide Research Symposium, 2019. April 1-5, 2019. Nashville, TN.
  • Type: Conference Papers and Presentations Status: Other Year Published: 2019 Citation: Holden, M., Simmons, T., Baysal-Gurel, F. 2019. First report of Fusarium crown rot of oakleaf hydrangea in Tennessee. Association of Research Directors, Inc. 19th Biennial Research Symposium. March 30 - April 3, 2019, Jacksonville, FL (Oral presentation second place).
  • Type: Conference Papers and Presentations Status: Other Year Published: 2019 Citation: Baysal-Gurel, F., Brown, M., Oliver, J., Addesso, K. 2019. Control of Phytophthora root rot and ambrosia beetles on flowering dogwood trees during simulated flood events. 96th Southern division APS meeting. Feb 7-9, 2019. Gainesville, FL.
  • Type: Conference Papers and Presentations Status: Other Year Published: 2018 Citation: Baysal-Gurel, F., Brown, M., Oliver, J., Addesso, K. 2018. Comparative performance of fungicides, biofungicides, and host plant defense inducers in suppression of Phytophthora root rot in flowering dogwood during simulated flood events. International Soilborne Oomycete Conference. December 4-6, 2018. Islomorada, FL.