Source: UNIVERSITY OF FLORIDA submitted to
SUSTAINABLE ORGANIC STRAWBERRY (SOS) CROPPING SYSTEMS FOR THE SOUTHEAST
Sponsoring Institution
National Institute of Food and Agriculture
Project Status
TERMINATED
Funding Source
OTHER GRANTS
Reporting Frequency
Annual
Accession No.
1007441
Grant No.
2015-51300-24134
Project No.
FLA-HOS-005472
Proposal No.
2015-07389
Multistate No.
(N/A)
Program Code
113.A
Project Start Date
Sep 1, 2015
Project End Date
Feb 28, 2021
Grant Year
2020
Project Director
Chase, C. A.
Recipient Organization
UNIVERSITY OF FLORIDA
G022 MCCARTY HALL
GAINESVILLE,FL 32611
Performing Department
AG-HORTICULTURAL SCIENCES
Non Technical Summary
The long-term goal of the project is to promote the expansion of organic strawberry production in the Southeast. We propose to develop organic strawberry cropping systems that are more environmentally and economically sustainable and resilient to weed, pest, and disease pressure. The project is a collaborative effort of the University and Florida (UF), North Carolina A&T State University (NCAT), Florida A&M University (FAMU), and Florida Certified Organic Growers and Consumers, Inc. (FOG).The project has three major components: biological research, consumer and economic research, and evaluation and outreach. The main open field experiment will be conducted at the UF Plant Science Research and Education Unit (PSREU) in north-central Florida. We will examine the effects of three cover crop treatments and a weedy control on soil health, nematode suppression, insect and mite pests, beneficial organisms, and the performance of four strawberry cultivars in open-field production.Four supporting or satellite, on-station studies will examine specific aspects of nutrient and pest management at the PSREU in Florida and high tunnel and low tunnel production systems at the NCAT Research Farm. The integration of cover crops and approved preplant fertilizer to satisfy the nitrogen fertility needs of organic strawberry will be investigated. Studies will be conducted to develop pest management practices for spotted wing drosophila (SWD) and twospotted spider mite (TSSM) in organic strawberry. The influence of adjacent woodlands on SWD populations and biological control of TSSM with spot treatments of predatory mites will be assessed and pest management materials approved for use in organic cropping systems will be evaluated for the control of both pests. The performance of strawberry cultivars in high and low tunnels, alone and in combination, for cold protection and season extension will be evaluated in North Carolina.Farmer-designed and implemented field trials will be conducted to evaluate selected cover crop and strawberry cultivar combinations. These on-farm studies allow the systems to be evaluated under the environmental and management regimes of a commercial operation and allow us to gain valuable insight from our farmer-collaborators.Consumer and economic research will include tests of consumer preference for intrinsic (e.g. color, size, shape, flavor, texture) and extrinsic (e.g. organic label, eco-label, sustainable and local labels) traits of organic strawberry, including traits based on production practices. We will utilize enterprise budgets and partial budget analysis to document the economic viability of selected cover crops, alternative nutrient management systems as well as the production management that exhibit superior biological performance for selected strawberry cultivars.The evaluation and extension components are integrated. We will use an Industry Liaison Panel and research assessments by growers and technical advisors to maintain stakeholder input throughout the project. The feasibility of low cost tunnels for organic strawberry production will be demonstrated in north Florida at FAMU. Extension activities will be conducted by each of the three institutions and will include field days, trainings, and workshops.
Animal Health Component
0%
Research Effort Categories
Basic
(N/A)
Applied
100%
Developmental
(N/A)
Classification

Knowledge Area (KA)Subject of Investigation (SOI)Field of Science (FOS)Percent
2051122106040%
2051122112010%
2051122113020%
2051122114010%
2051122301010%
2051122309010%
Knowledge Area
205 - Plant Management Systems;

Subject Of Investigation
1122 - Strawberry;

Field Of Science
1060 - Biology (whole systems); 1120 - Nematology; 1130 - Entomology and acarology; 3090 - Sensory science (human senses); 1140 - Weed science; 3010 - Economics;
Goals / Objectives
LONG-TERM GOALThe long-term goal of the project is to promote the expansion of organic strawberry production in the Southeast. We propose to develop organic strawberry cropping systems that are more environmentally and economically sustainable and are resilient to weed, pest, and disease pressure. Organic strawberry production has increased in the U.S. in recent years, including in the Southeast region. However, organic strawberry growers have a number of critical needs that must be addressed to protect the viability of the industry and to sustain growth.RESEARCH OBJECTIVESBIOLOGICAL RESEARCHResearch Objective 1: Assess the Efficacy of Off-Season Cover Crops on Soil Health and in Suppressing Weeds, Sting Nematodes, Arthropod Pests, and Pathogens.Research Objective 2. Evaluate the Performance of Strawberry Cultivars in Open Field Organic Production Systems.Research Objective 3: Monitor Population of Arthropod Pests, Including the Spotted Wing Drosophila (SWD) and Twospotted Spider Mite (TSSM), and Beneficials.Research Objective 4: Integrate Summer Leguminous Cover Crop into Nutrient Management Program for Organic Strawberry Production Systems.Research Objective 5: Develop Pest Management Practices for Spotted Wing Drosophila.Research Objective 6: Develop Management Alternatives for Twospotted Spider Mite.Research Objective 7: Assess the Season Extension Potential of Low and High Tunnels in Organic Strawberry Production.Research Objective 8: Farmer assessment of response of cover crop and cultivars to on-farm bio-physical and management regimes.CONSUMER AND ECONOMIC RESEARCHResearch Objective 9: Evaluate consumer preferences for traditional and recently released strawberry cultivars with regard to sensory attributes like flavor, color, and texture, including consumer willingness to pay.Research Objective 10: Calculate Production Costs and Potential Returns of Selected Management Alternatives Based on Data from the Biological Research.OUTREACH OBJECTIVESThe outreach component of this project provides is an integrated approach to stakeholder involvement, evaluation and dissemination of research results and recommendations to a large and diverse group of growers and technical advisors.Outreach objective 1: We will engage producer and county Extension faculty members in research and outreach planning, implementation and outcomes. An Industry Liaison Panel representing growers and industry representatives from a diverse group of formal and informal networks will provide overall guidance for this project.Outreach objective 2: We will demonstrate the feasibility of organic strawberry production in low cost crop tunnels. Small growers in areas where cool temperatures limit the strawberry production system have expressed interest in adapting research from the high tunnel production system to a lower cost protected system.Outreach objective 3: We will provide Extension faculty members, other local service providers, and growers with research results and recommendations, including representatives of and professionals who work with limited resource and minority farmers. This objective addresses the need to increase the number of service providers and grower representatives who help expand organic strawberry production geographically and to diversify strawberry grower populations and conditions in the Southeast.
Project Methods
Biological ResearchThe main on-station experiment in Florida will address the relationships between cover crops and strawberry cultivars in open field organic production systems. We will monitor the effects on soil health, weed infestation, and plant-pathogenic nematode populations of the cover crop treatments: (1) Crotalaria juncea (sunn hemp), (2) Indigofera hirsuta (hairy indigo), and (3) a four-way legume mix with sunn hemp, hairy indigo, Aeschynomene americana (American jointvetch), and C. ochroleuca (slenderleaf rattlebox). A no cover crop control will also be included.Four strawberry cultivars: SensationTM Brand 'Florida127', WinterstarTM, 'Florida Radiance', and 'Strawberry Festival' will be evaluated for their responses to the cover crop treatments. Plant growth parameters and yield of marketable and cull fruit will be assessed and disease incidence will be monitored. Fruit quality, health-promoting properties, and shelf-life of strawberries in relation to cultivar and the use of cover crops will also be determined.In both the main on-station experiment and on-farm experiments, we will monitor the populations of two key pests spotted wing drosophila (SWD) and twospotted spider mites (TSSM) as well as beneficial arthropod populations such as six-spotted thrips, bigeyed bugs, and minute pirate bugs. Other pests that will be monitored include: flower thrips, aphids, whiteflies, seed bugs, and armyworms.In an on-station supporting experiment, performance of SensationTM Brand 'Florida127' strawberry will be evaluated under two preplant fertilization levels: 40 and 80 lbs available nitrogen (N) per acre using Microstart60 3-2-3. With each level, there will be four treatments investigating N credit from sunn hemp: 1) Summer weedy control + preplant fertilization; 2). Sunn hemp without N credit + preplant fertilization; 3) Sunn hemp with 20% N availability from aboveground biomass + reduced preplant fertilization; and 4) Sunn hemp with 40% N availability + reduced preplant. Nitrogen nutritional status will be monitored and fruit yield and quality will be assessed.Pest management practices for SWD will also be developed. Baited traps will be deployed at varying distances from field edges into wooded areas to detect movement of SWD from adjacent woodlands into strawberry fields. Traps installed within the woods will serve as a control. We also will compare the efficacy of Grandevo®, Azera® and Veratran DTM to the standard organic pesticide, Entrust®, for the control of SWD in strawberries. Trapping and fruit samples will be used to assess SWD population.The development of management alternatives for TSSM will include evaluation of site-specific application of the predatory mite Neoseiulus californicus and evaluation of OMRI-approved pesticides. N. californicus treatments will be evaluated: 1) spot treatment 2) whole plot treatment, and 3) untreated. Four OMRI-approved pesticides will be will be evaluated using the cultivar WinterstarTM: 1) Sulfur, 2) Aramite™, 3) Safer® soap, and 4) an untreated control. Motiles and eggs of TSSM will be assessed on randomly collected trifoliate leaves.The season extension potential of low and high tunnels for organic strawberry production will be assessed at the North Carolina A&T State University research farm.Fall production of day-neutral strawberries in low tunnels. Day-neutral cultivars Albion and San Andreas will be planted in four low tunnels with unprotected plots of each cultivar as controls three planting dates (July 15, July 30 and August 14). Data collection for this and the next two studies will include: plant growth, phenology, yield, fruit quality, pest incidence and severity, length of the harvesting season, and fixed and variable costs (for materials and labor). Plants will go dormant in winter and resume growth and production the next season. Low tunnels will be removed during the dormancy period and replaced in February.Spring production of day-neutral and June-bearing strawberries in low tunnels. Day neutral (Albion and San Andreas) and June-bearing (Radiance and WinterstarTM) cultivars will be planted in October. The raised beds will be covered with row covers in winter. In late January, four low tunnels will be installed on the day-neutral plots and another four will be installed on the June-bearing plots. Plants not covered with low tunnels will serve as controls.Fall, winter and spring production of day-neutral and June-bearing strawberries in high tunnels and in low tunnels within a high tunnel. Albion, San Andreas, Radiance and WinterstarTM cultivars using two high tunnels, one for day-neutral strawberries, another for June-bearing cultivars. Six raised beds will be formed in each high tunnel, three of which will be covered with row covers. There will be three planting dates (July 15, August 15 and September 15). Fertility will be managed to discourage plants from entering into dormancy in winter.Experiments will be conducted by farmer-collaborators to determine the performance of cover crops and strawberry cultivars under on-farm bio-physical and management regimes. Farmers will select the cover crop and cultivar combinations that they find most interesting for the trials and will collect all data. Team members will confer with the farmer on-site at critical points during the production season, such as termination of cover crops, plant establishment, and onset of fruit set. We will make visual recordings of the plots (pictures and/or video) and record our own direct observations. However, the purpose of these trials is not to direct the experiments, but rather to benefit from the farmers' experience and innovation.Consumer & Economic Research Both intrinsic (color, size etc) and extrinsic (organic label, eco-label etc) attributes affect consumer preferences for a product. We will use sensory evaluations, experimental auctions and online surveys to determine the impact of fresh strawberry intrinsic and extrinsic attributes on consumer willingness to pay for fruits from cultivars included in field testing.Enterprise budgets will be developed for selected cover crops, cultivars, pest management, and alternative nutrient management regimes based on superior biological performance. Partial budget analysis will be used to estimate economic return of selected production treatments in comparison with the relevant control. We will also conduct sensitivity analysis based on various yield and market prices to draw more robust conclusions on the economic variability of alternative cover crops, different nutrient management systems and production management choices based on treatments that exhibit superior biological performance.Evaluation & OutreachAn integrated approach to stakeholder involvement, evaluation and dissemination of research results and recommendations to a large and diverse group of growers and technical advisors will be used:Engagement of producer and county Extension faculty members in research and outreach planning, implementation and outcomes. An Industry Liaison Panel representing growers and industry representatives will provide overall guidance for this project.Demonstration of the feasibility of organic strawberry production in low cost crop tunnels at Florida A&M University. Small growers in areas where cool temperatures limit the strawberry production system have expressed interest in adapting the research to a lower cost system.Providing Extension faculty members, other local service providers, and growers with research results and recommendations, including representatives of and professionals who work with limited resource and minority farmers. This will increase the number of service providers and grower representatives who can help to expand organic strawberry production geographically and diversify strawberry grower populations and conditions in the Southeast.

Progress 09/01/15 to 02/28/21

Outputs
Target Audience:Certified organic and transitional organic strawberry growers and producers who are interested in organic strawberry production, service providers, extension personnel, other researchers, educators, and stakeholders. Changes/Problems:Due to the COVID-19 pandemic, scheduling laboratory work has been rather challenging. What opportunities for training and professional development has the project provided?Graduate students who have completed their degrees were mentored in the preparation of refereed journal articles. One doctoral student actively led the laboratory work. In addition, that student has been focusing on data analysis and manuscript writing. How have the results been disseminated to communities of interest?Some of the research results have been published in refereed journals. Other manuscripts are in press, in review, and in preparation and are expected to be published in 2021 and 2022. Also, we are disseminating research results at scientific meetings and through a series of virtual field day videos on YouTube. What do you plan to do during the next reporting period to accomplish the goals? Nothing Reported

Impacts
What was accomplished under these goals? Res. Obj. 1: Sunn hemp ('Tropic Sun') and hairy indigo, and a 4-way mix of sunn hemp ('AU Golden'), hairy indigo, slenderleaf rattlebox, and American jointvetch were compared with a no cover crop control. For biological control of Botrytis cinerea, mowed cover crop residues were treated with microbial antagonists Trichoderma spp. and Gliocladium catenulatum and incorporated into the soil before bed formation. Additionally, a weekly biofungicide application of either Actinovate® or DoubleNickel™ was compared to biofungicide application only after rainfall events for botrytis management. Marketable fruit number and fruit weight with combinations of cover crops and microbial antagonist-treated residue were not significantly different from the marketable fruit yields with the untreated, weedy control. Reducing foliar biofungicide sprays to after rainfall events instead of weekly (a 30% reduction) did not decrease marketable fruit number and fruit weight, which would reduce production costs for growers. The lack of significant effects with cover crops and microbial antagonists in 2020-2021 may be due to our use of a field with no prior history of strawberry production and likely a relatively low incidence of strawberry pathogens. This result emphasizes the value of crop rotation for organic strawberry production. Res. Obj. 2 and 3 were complete at the end of the 2018/19 season. Res. Obj. 4: Assessment of fruit quality attributes including soluble solids content (SSC), titratable acidity (TA), pH, and total anthocyanin content (TAC) was completed on frozen samples from the nutrient management and biostimulant trials during the 2019-2020 season. In the nutrient management trial using 'Florida Brilliance' strawberry, sunn hemp treatment and vermicompost application significantly increased SSC compared with the weedy fallow and no compost controls, respectively, in the December harvest. Two cultivars (Florida127 and Florida Brilliance) were evaluated in the biostimulant experiment. 'Florida 127' had higher levels of SSC and TA than 'Florida Brilliance' at all sampling dates, but TAC was significantly higher in 'Florida Brilliance'. Combination of Stimplex® (seaweed extract) and TerraGrow® (microbial biostimulant) significantly increased SSC in contrast to the water control at early harvest and during the late season. EndoMaxx® (mycorrhizal biostimulant) had significant effect on strawberry fruit quality attributes. Res. Obj. 5 and 6 were complete at the end of the 2018/19 season. Res. Obj. 7: We identified cultivars that are suited for organic high tunnels production in North Carolina. We also found that low tunnels inside high tunnels would not increase the early yield but not the total yield. Low tunnels also did not enhance strawberry fruit quality. Low tunnels could be a good option for the high tunnel system only if appropriate day-neutral or June-bearing cultivars were selected. Low tunnels are a good choice for field strawberry productions for both June-bearing and day-neutral strawberries. Res. Obj 8 was complete at the end of the 2018/19 season. Res. Obj 9: Most data related to this objective were collected in the 2019-2020 period. Additional pilot data to examine the effect of organic food availability on consumer store selection and factors affecting consumer purchase of organic strawberries were collected in 2020-2021. More data will be collected for full analysis. Res. Obj. 10: The student working on the objective has graduated. Therefore, there are no activities related to this objective in 2020-21. Outreach obj.1 was completed during 2019-2020. Outreach obj. 2: In the Florida A&M University demonstration trials in the open field (OF) no significant difference in mean yield was observed among the 4 cultivars compared: 'Florida Brilliance', 'Florida Beauty', 'Florida Radiance', and 'Florida127'. In the low-cost high tunnel (LCHT) yields were generally about double that of the OF. However, the yield obtained with 'Florida Beauty' in the LCHT was significantly higher than with the other 3 cultivars; wheras the yields obtained with 'Florida Radiance', 'Florida Brilliance'. and 'Florida127' did not differ significantly. Outreach obj. 3: We have developed a series of virtual field day videos to disseminate on YouTube, through our website, and other relevant email listservs. Videos are in the final stage of production. They cover the most promising treatments from this project from cover crop through final harvest.

Publications

  • Type: Conference Papers and Presentations Status: Published Year Published: 2020 Citation: Rhodes, E. M., C. A. Chase, X. Zhao, and O. E. Liburd. 2020. The effect of cultivar and runner removal on strawberry seed bug, Neopamera bilobata, density and fruit injury. Entomological Society of America Annual Meeting. Virtual.
  • Type: Conference Papers and Presentations Status: Accepted Year Published: 2021 Citation: Chase, C.A. and E. Torres Quezada. 2021. Sustainable management of disease in organic strawberry with cover crops, soil-applied microbial antagonists, and foliar biofungicides. American Society for Horticultural Science Meeting, Denver, CO
  • Type: Journal Articles Status: Under Review Year Published: 2021 Citation: DeLong, A.N., Ruiz-Menjivar, J., Swisher, M.E., Irani, T. & Chase, C.A. Who will feed our future? A systematic literature review of new and beginning organic farmers. Journal of Agriculture, Food Systems, and Community Development.
  • Type: Theses/Dissertations Status: Published Year Published: 2020 Citation: DeLong, A.N. 2020. Farmer decision-making: A new generation of new and beginning farmers. [Doctoral dissertation, University of Florida, Gainesville]. ProQuest Dissertations Publishing.
  • Type: Journal Articles Status: Awaiting Publication Year Published: 2021 Citation: Gu S. and T. S. Rana. 2021. Growth, Yield and Fruit Quality of Organic Day-neutral Strawberry in Field and Low Tunnel Settings in the Southeast United States. Acta Horticulturae.
  • Type: Journal Articles Status: Awaiting Publication Year Published: 2021 Citation: Gu S. and A. Ballard. 2021. Low Tunnels Increased Early-season Yield of Organic June-bearing Strawberries in Southeastern United States. Acta Horticulturae.
  • Type: Journal Articles Status: Submitted Year Published: 2021 Citation: Rana S. T. and S. Gu. 2021. Resource Accumulation and Allocation of Organic High Tunnel Day-neutral Strawberries Grown with or without Low Tunnels. Agronomy.
  • Type: Journal Articles Status: Other Year Published: 2021 Citation: DeLong, A.N., Swisher, M.E., Chase, C.A., Zhao, X., Liburd, O.E., Gao, Z., Bolques, A. & Gu, S. Stakeholder-driven adaptive research (SDAR): Better solutions for farmers  faster. Renewable Agriculture and Food Systems.
  • Type: Journal Articles Status: Other Year Published: 2021 Citation: DeLong, A.N., Swisher, M.E., Ruiz-Menjivar, J., Irani, T. & Chase, C.A. (2021, in preparation). The roots of first-generation farmers: The role of inspiration in farmer-decision making. Agriculture and Human Values.
  • Type: Journal Articles Status: Published Year Published: 2021 Citation: Li, J., X. Zhao, G. Maltais-Landry, and B.R. Paudel. 2021. Dynamics of soil nitrogen availability following sunn hemp residue incorporation in organic strawberry production systems. HortScience 56:138-146.
  • Type: Journal Articles Status: Submitted Year Published: 2021 Citation: Li, J., X. Zhao, L.S. Bailey, M.N. Kamat, and K.B. Basso. 2021. Identification and characterization of proteins, lipids, and metabolites of two organic fertilizer products derived from different nutrient sources. Soil Biology and Biochemistry (submitted).
  • Type: Book Chapters Status: Published Year Published: 2021 Citation: Liburd, O. E. and E. M. Rhodes. 2021. Management of Drosophila suzukii in berry crops. In Drosophila suzukii Management, F. R. M. Garcia ed. Springer Nature Switzerland. London, UK. https://doi.org/10.1007/978-3-030-62692-1_12
  • Type: Journal Articles Status: Published Year Published: 2020 Citation: Talton, H. R., E. M. Rhodes, C. A. Chase, M. E. Swisher, J. M. Renkema, and O. E. Liburd. 2020. Effect of cultural practices on Neopamera bilobata in relation to fruit injury and marketable yields in organic strawberries. Insects. 11: 843. 17 pp.
  • Type: Journal Articles Status: Accepted Year Published: 2021 Citation: Olaniyi, O. G., E. M. Rhodes, C. A. Chase, and O. E. Liburd. 2021. The effect of summer cover crops and strawberry cultivars on the twospotted spider mite, Tetranychus urticae (Acari: Tetranychidae) and the predatory mite, Neoseiulus californicus (Acari: Phytoseidae) in organic strawberry production systems in Florida. Journal of Economic Entomology.
  • Type: Journal Articles Status: Awaiting Publication Year Published: 2020 Citation: Bolques, A., Queeley, G., Ospina F., and Richardson, V. (2020). Low cost high tunnel versus open field production of organically grown strawberries in north Florida: A three-year evaluation. Proc. Fla. State Hort. Soc. 133
  • Type: Conference Papers and Presentations Status: Submitted Year Published: 2020 Citation: Bolques, A., Queeley, G., Ospina F., and Richardson, V. (2020). Low cost high tunnel versus open field production of organically grown strawberries in north Florida: A three-year evaluation. The 133rd Annual Meeting of the Florida. State Horticultural Society, Virtual Conference, 10/19/2020.
  • Type: Other Status: Published Year Published: 2021 Citation: Bolques, A., and Queeley G. (2020). Low cost high tunnel for season extension and overwintering of crops. FAMU ANR Protected Ag, BULLETIN PA001.
  • Type: Other Status: Submitted Year Published: 2021 Citation: Bolques, A., and Queeley G. (2021). Low cost high tunnel structural modifications. FAMU ANR Protected Ag, FACT SHEET PA002.
  • Type: Journal Articles Status: Other Year Published: 2021 Citation: Torres-Quezada, E.A. C.A. Chase, and M.E. Swisher. 2021. Cover crop alternatives for a resilient organic strawberry production system in Florida. HortTechnology


Progress 09/01/19 to 08/31/20

Outputs
Target Audience:Certified organic and transitional organic strawberry growers and producers who are interested in organic strawberry production, service providers, extension personnel, other researchers, educators, and stakeholders. In North Florida, the audience targeted were organic farm producers including smallholders, small farm and urban farm growers from the Gadsden, Leon, Jefferson, and Wakulla Counties and bordering southwest Georgia counties of Thomas, Grady and Decatur. Workshops at the FAMU Research and Extension Center in Quincy, FL are focused on small farm populations, indigenous farmers, black farmers, farmers of color and their communities. At North Carolina A&T the target audiences are small farmers who are interested in growing organic strawberries in both field and protected production systems, and selling strawberries in direct markets, extension educators and other agricultural professionals who work with strawberry and high tunnels, and the general public interested in strawberry and local food production. Changes/Problems:Due to restrictions on research as a result of the COVID-19 pandemic, we were not able to follow our regular harvest schedule later in the season for the organic strawberry nutrient management and biostimulant trials and had to terminate them earlier than planned. Moreover, some other data collection activities were no longer feasible, and some measurements were missed later in the season. In addition, lab work had to be postponed because of various restrictions as a result of COVID challenges. A sensory experiment was planned for spring 2020. However, because of the COVID-19 pandemic, the sensory experiment was canceled. We then decided to conduct an online survey in the southern US. Despite the changes, using online survey did not affect our ability to accomplish the research objectives related to the consumer research. For objective 3, we could not establish and maintain a seed bug colony in the laboratory, so we were unable to conduct planned fruit injury studies. The FAMU SOS project experienced two major problems. First was Hurricane Michael in October 2018 (previously reported) and COVID-19 in March 2020. Due to COVID we had to postpone 2 planned educational activities as part of the SOS plan of work. We are hopeful that we would be able to get one of these accomplished before the end of the COVID-19 no-cost extension. What opportunities for training and professional development has the project provided?The project provided opportunities to network with partners at the University of Florida and through conference attendance at the Florida State Horticultural Society. Participating graduate students and faculty gave oral and poster presentations at the virtula American Society for Horticultural Science meeting. This was in lieu of presenting at a scheduled International Strawberry Symposium in May 2020, which was postponed to 2021 due to the Covid-19 pandemic. We also provided one training for service providers familiar with organic strawberry cropping systems. Two graduate students have been trained with survey design, experimental design, and data analysis. How have the results been disseminated to communities of interest?Results from research done at University of Florida were presented at the American Society for Horticultural Science 2020 Annual Conference (Virtual Conference). Additionally, we disseminated project research results through a series of videos on YouTube. At FAMU, thus far, two Florida State Horticultural Society (FSHS) journal papers on low cost high tunnel versus open field production of organically grown strawberries in North Florida were published. A third paper was scheduled for presentation at the 133rd FSHS virtual annual meeting in fall 2020. Additionally, a farm tour consisting of 10 participants was conducted on July 23 and August 20, 2020 following COVID-19 guidelines to a group of new and beginning farmers and ranchers. Three Farmer's Survival Guide Zoom/webinars were conducted on July 7th and July 11, 2020. Information about the SOS project and educational opportunities were included in the FAMU Extension Strikes newsletter and clientele direct email listing. What do you plan to do during the next reporting period to accomplish the goals?Objectives 1. and 2. Data analysis will be completed and manuscripts will be submitted to journals. Objective 3. Complete and publish three scientific papers, one each on TSSM, SWD, and seed bugs, and an extension publication on seed bugs that are in progress. Produce a video on seed bug management in organic strawberries in Florida. Objective 4. During the next reporting period, we plan to conduct cost-return analysis based on data from the field trials to determinate the economic feasibility of using a sunn hemp cover crop, different organic fertilization programs, and biostimulants tested for organic strawberry production. Fruit quality assessment of the frozen samples will also be completed. In addition, soil sample analysis will be finished to conclude the N mineralization study during the next reporting period. Research findings from the 2019-2020 season will be presented at professional conferences in 2021. Objective 7. Peer-reviewed publications will be released. Objective 8. We will develop a survey to investigate the impact of organic product assortment on consumer preference for grocery stores using a national representative sample. We plan to prepare the technical reports and journal articles based on the analysis of the survey data. Outreach Objective 2. We plan to have a final project field day in February 2021. Facts sheets in progress will be finalized and available as hand-outs along with conference papers published. The fact sheets will include updated cost estimates.

Impacts
What was accomplished under these goals? Research Objective 1. Sunn hemp ('Tropic Sun') and hairy indigo monoculture cover crops, and a 4-way mix of sunn hemp ('AU Golden'), hairy indigo, slenderleaf rattlebox, and American jointvetch were compared with a no cover crop control. Sunn hemp produced 53% higher biomass than the rest of the treatments, while hairy indigo and the 4-way mix produced 78% higher density than sun hemp. There was no cover crop effect on plant growth parameters, or soil health. Cover crop biomass was treated with Trichoderma spp. and Gliocladium catenulatum after termination, and integrated into the soil before bed formation. Additionally, a weekly biofungicide foliar application was compared to application only after rainfall events for botrytis management. There was no difference between weekly fungicide applications and applications triggered by occurrence of rainfall on disease-nfested fruit. Spray application of G. catenulatum on the cover crop biomass before strawberry planting resulted in a 10% increase in organic strawberry yield. Objective 2. We evaluated the performance of strawberry cultivars in open field organic production systems over three seasons in the main on-station experiment in Citra, Florida. Data are currently being analyzed and a manuscript is under preparation. Objective 3. Spotted wing drosophila (SWD) population was monitored in the main on-station experiment with yeast sugar water traps over three seasons. This objective was complete at the end of the 2018-2019 season and was not repeated this year. Objective 4. Sunn hemp cover crop, vermicompost application at transplanting, and three different organic fertilization programs were investigated. The Florida Brilliance strawberry cultivar was used. Sunn hemp significantly increased marketable strawberry fruit yield in November and December and total strawberry fruit yield in November, December, and January. Vermicompost did not significantly impact fruit yield but increased marketable fruit yield. No significant difference was observed in strawberry fruit yield between the two application rates of liquid fish fertilizer (1.6 kg N ha-1 day-1 vs. 1.1 kg N ha-1 day-1) in the early season. The biostimulant, Stimplex® and TerraGrow® were evaluated with 'FL127' and 'Florida Brilliance. Compared to the water control, the combination of seaweed extract and microbial biostimulants significantly increased strawberry marketable fruit yield. Objective 5. To detect movement of SWD from adjacent woodlands into a strawberry field at a commercial organic farm, baited traps were deployed at 10-m intervals from the field border into the field. More SWD were caught in the woodlands' traps than in the strawberry field. We repeated the trial to compare Grandevo®, Azera®, Veratran DTM, and Entrust® from Mar. 7 to 21 for managing SWD. There were no differences in adult trap catch among treatments and no larvae were collected from fruit samples. This objective was complete at the end of 2019 and not repeated this year. Objective 6. To develop management alternatives for TSSM, spot treatment of N. californicus was compared with whole plot treatment, and a nontreated control. The preventative release of N. californicus did not establish so no difference in TSSM population occurred. This objective was complete at the end of 2019 and not repeated this year. Objective 7. At North Carolina A&T we have completed 2 seasons of field and high tunnel research projects and have been working on journal publications. We continued some strawberry demonstrations in low tunnel/high tunnel and greenhouse. In 2019/20, no major research activities occurred. We focused on research data analysis and manuscript preparation. Objective 8. On-farm research was conducted with the same cover crops as in the main on-station trial in Citra Florida and 3 cultivars: 'Florida Brilliance', 'FL127' and 'Florida Radiance'. In Hawthorne, broadleaf weed biomass was reduced by sunn hemp and the 4-way mix compared to hairy indigo, while in Gainesville, there was no effect of cover crops on weed biomass. In Gainesville, 'Brilliance' and 'Radiance' produced 41% higher yield than 'FL127', while in Hawthorne, there was no difference in yield among cultivars. This objective was complete at the end of last season and not repeated this year. Objective 9. A survey has been developed to study the important attributes for consumer strawberry purchase, and consumer perception and Willingness to Pay for organic strawberries in 2019-2020. More than 60% of participants agreed that organic strawberries were more environmentally friendly, and beneficial to local and small famers than conventional strawberries. About 65% of participants considered organic strawberries more expensive than conventional ones. Participants were willing to pay significantly more for organic strawberries ($3.47/pound for organic vs $3.15/pound for conventional). Objective 10. We calculated the production costs and potential returns of selected management alternatives based on data from the biological research. This objective was complete at the end of 2019 and was not repeated this year. Outreach Objective 1. We conducted three grower research assessments: one on-station in February 2020 and two virtual in August 2020. Local strawberry producers assessed our research plots and provided feedback regarding what they liked about our research. We will use this feedback to design future research projects. Farmers who participated found the most promising treatment to be a fertilization regime of 40 lbs/acre with sunn hemp and an in-season fertigation/preplant fertilizer combination. Topics with the most interest are new combinations of cover crop mixes, alternatives to plastic mulch, and using cover crops to add soil organic matter. Farmers are interested in protected agriculture but do not have the full economic picture needed to make an informed decision. Objective 2. Sunn hemp was planted and terminated 4 weeks later. Sunn hemp residue was incorporated back into the soil by disking. Four strawberry cultivars (FL127; Florida Brilliance; Florida Radiance; Florida Beauty) were grown in each production system. The cultivars were grown in open-field (OF) and under the protection of a low-cost crop tunnel (LCHT). The three-year average yield from the LCHT and OF treatments were 1744 lbs./ac and 949 lbs./ac respectively. The yield obtained from the LCHT was significantly higher. The study concluded that the LCHT is a sustainable alternative to OF production of strawberries in north Florida. Objective 3. We conducted one training with service providers familiar with organic cropping systems. Local service providers assessed our research plots and provided feedback regarding what they liked about our research, what they disliked, and what was missing that we should consider in the future. There was a total of 6 technical advisers who participated in the on-station research assessment. They found the most promising treatment to be (1) 40 lbs/acre sunn hemp with an early push of in-season fertigation with no preplant fertilizer and (2) vermicompost and 40 lbs/acre sunn hemp with a late push of in-season fertigation with no preplant fertilizer.

Publications

  • Type: Conference Papers and Presentations Status: Published Year Published: 2020 Citation: DeLong, A.N., Swisher, M.E., Chase, C.A., Ruiz-Menjivar, J. & Irani, T. 2020. Emerging identities of a new generation of farmers: A systematic literature review. HortScience 55(9) Supplement:S27
  • Type: Conference Papers and Presentations Status: Published Year Published: 2020 Citation: Swisher, M.E., DeLong, A., Sattanno, K., Chase, C.A., Zhao, X., Liburd, O.E., Gao, Z., Bolques, A. & Gu, S. 2020. Farmer driven research design: Developing more adoptable research outcomes. HortScience 55(9) Supplement:S48
  • Type: Conference Papers and Presentations Status: Published Year Published: 2019 Citation: Bolques, A., Queeley, G., Ospina F., and Richardson, V. 2019. Low cost high tunnel versus open field production of organically grown strawberries in north Florida: Second year evaluation. Proc. Fla. State Hort. Soc. 132, 120-122.
  • Type: Conference Papers and Presentations Status: Submitted Year Published: 2020 Citation: Bolques, A., Queeley, G., Ospina F., and Richardson, V. (2020). Low cost high tunnel versus open field production of organically grown strawberries in north Florida: A three-year evaluation [Abstract] The 133rd Annual Meeting of the Florida. State Horticultural Society (Virtual, October 19-20th)
  • Type: Journal Articles Status: Published Year Published: 2020 Citation: Rana S. T., S. Gu and J. Yu. 2020. Effect of Low Tunnels and Planting Dates on the Fruit Quality of Organic Day-Neutral Strawberries in High Tunnels in North Carolina. International Journal of Fruit Science. DOI: 10.1080/15538362.2020.1774475.
  • Type: Journal Articles Status: Published Year Published: 2020 Citation: Rana S. T. and S. Gu. 2020. Growth and Yield of Organic Day-neutral Strawberries in Low Tunnels inside High Tunnel in North Carolina. HortScience 55(3):336343. 2020. https://doi.org/10.21273/HORTSCI14491-19.
  • Type: Journal Articles Status: Published Year Published: 2020 Citation: Fernandez G., J. Pattison, P. Perkins-Veazie, J. Ballington, E. Clevinger, R. Schiavone, S. Gu, J. Samtani, E. Vinson, A. McWhirt and J. G. Chacon. 2020. 'Liz' and Rocco strawberries. HortScience.55(4) 597-600. https://doi.org/10.21273/HORTSCI14516-19.
  • Type: Journal Articles Status: Submitted Year Published: 2021 Citation: Rana S. T. and S. Gu. Resource Accumulation and Allocation of Organic High Tunnel Day-neutral Strawberries Grown with or without Low Tunnels. HortScience.
  • Type: Conference Papers and Presentations Status: Submitted Year Published: 2021 Citation: Gu S. and S.T. Rana. Growth, Yield and Fruit Quality of Organic Day-neutral Strawberry in Field and Low Tunnel Settings in the Southeast United States. Acta Horticulturae.
  • Type: Journal Articles Status: Under Review Year Published: 2021 Citation: Rana S.T. and S. Gu. Resource Allocation of Organic Day-neutral Strawberries in Low Tunnels and Field in North Carolina. HortTechnology.
  • Type: Journal Articles Status: Under Review Year Published: 2021 Citation: Ballard A. and S. Gu. Performance of Organic June-bearing Strawberries Grown in High Tunnels with Low Tunnels in the Southeast. HortTechnology.
  • Type: Conference Papers and Presentations Status: Published Year Published: 2020 Citation: Liburd, O., H. Talton, E.M. Rhodes, C.A. Chase, and M.E. Swisher. 2020. Assessing strawberry seed bug injury in organic strawberries and using cultural techniques to manage its population. HortScience 55(9) Supplement: S165.
  • Type: Journal Articles Status: Accepted Year Published: 2020 Citation: Li, J., X. Zhao, G. Maltais-Landry, and B.R. Paudel. 2020. Influence of Sunn Hemp, Vermicompost, and Organic Fertilizers on Nitrogen Availability and Organic Strawberry Production. HortScience 55(9) Supplement: S187.
  • Type: Conference Papers and Presentations Status: Published Year Published: 2020 Citation: Li, J., X. Zhao, B.R. Paudel. 2020. Seaweed extract and microbial biostimulants show synergistic effects on organic strawberry production. HortScience 55(9) Supplement: S333.
  • Type: Conference Papers and Presentations Status: Published Year Published: 2020 Citation: Chase, C.A. and E.A. Torres Quezada. 2020. Optimizing microbial antagonist use for disease management in organic strawberry. Carlene A. Chase and Emmanuel A Torres Quezada. HortScience 55(9) Supplement: S166-S167.
  • Type: Book Chapters Status: Published Year Published: 2019 Citation: Liburd, O. and E. Rhodes. 2019. Management of strawberry insect and mite pests in greenhouse and field crops. In: Strawberry Pre- and Post-Harvest Management Techniques for Higher Fruit Quality. T. Asao and M. Asaduzzaman (eds). IntechOpen, London, United Kingdom. Pp. 101-119.
  • Type: Journal Articles Status: Accepted Year Published: 2020 Citation: Li, J., X. Zhao, G. Maltais-Landry, and B.R. Paudel. 2020. Dynamics of soil nitrogen availability following sunn hemp cover crop residue incorporation in organic strawberry production systems. HortScience


Progress 09/01/18 to 08/31/19

Outputs
Target Audience:Certified organic and transitional organic strawberry growers and producers who are interested in organic strawberry production, service providers, Extension personnel, other researchers, educators, and stakeholders. At North Carolina A&T: The target audiences are small farmers who are interested in growing organic strawberries in both field and protected production systems, and selling strawberries in direct markets, extension educators and other agricultural professionals who work with strawberry and high tunnels, and the general public who interested in strawberry and local food production. Changes/Problems:Research Objectives 2, 4, and 8: Plant disease management continued to be a major challenge during the organic strawberry production season. Research Objective 3: The only major problem was that the preventative releases of N. californicus did not establish in the main on-station trial and the OMRI-approved pesticide efficacy trial. This led to the failure of the preventive release treatment in the efficacy trial plot. However, in the main plot, this establishment failure did not cause any major issues. Research Objective 7: At North Carolina A&T, our plugs for the fertility pilot study were not conditioned enough so no flowers were produced in the fall of 2018. We also lost the graduate student as he took a job in industrial hemp. The replacement graduate student had a problem with graduate student paperwork, and when it was corrected, he decided to choose a different crop for his study. These challenges impeded the fertility research although this part of research was not included in the original proposal. Outreach Objective 2: At Florida A&M, Hurricane Michael resulted in conditions that prevented the setup of the low-cost high tunnels after strawberry planting. Therefore, strawberry yield data were collected as open field treatments only. As a result, we have requested a no-cost extension to accomplish the project outreach objective in the 2019-20 strawberry production season. What opportunities for training and professional development has the project provided?We trained 2 undergraduate students how to conduct arthropod research in strawberries. Also, we provided training opportunities to both MS and Ph.D. students, and a visiting research scholar from Brazil. A postdoctoral research associate attended a training course on geograhic information systems at University of Florida and the Growing Horticulturists career workshops at the American Society for Horticultural Sciences conference. We provided one training (described above) for service providers familiar with organic cropping systems. Local service providers assessed our research plots and provided feedback regarding what they liked about our research, what they disliked, and what was missing that we should consider in the future. In exchange, Certified Crop Advisors could receive up to three Continuing Education Units (CEUs). At North Carolina A&T research results were presented at the 2018 NC State Extension Conference, November 13-16, 2018 in Raleigh, NC, at an organic strawberry production with low and high tunnels agent training, and at the 2019 Southern Region ASHS Conference, February 1-4, 2019 in Birmingham, AL. How have the results been disseminated to communities of interest?At University of Florida, results were presented in two field days directed to growers and extension agents, and during advisory council meetings. All three institutions presented research results during the conference workshop at the North American Strawberry Symposium. Researchers, students, and postdoctoral research associates were authors and co-authors of presentations at the North American Strawberry Symposium and the annual meeting of the American Society of Horticultural Science. North Carolina A&T also did the follwing: presented research results at the 2018 Southeast Strawberry Expo, November 7-9, 2018 in Winston-Salem; offered a training on organic strawberry production with low and high tunnels at the North Carolina State Extension Conference (November 13-16, 2018); and visited over 10 strawberry growers in the state. What do you plan to do during the next reporting period to accomplish the goals?Research Objective 1: Results from 2016 to 2019 will be compiled for publication in refereed journals and research findings will be presented at scientific conferences in 2020. Measures for improving disease management will be assessed with the two most promising strawberry cultivars. Research Objective 2: Fruit quality assessment including soluble solids content and titratable acid and data analysis will be completed for the strawberry cultivars. Research findings from the 2018-2019 season will be presented at professional conferences in 2020. Research Objective 3: We have included a sub-objective on strawberry seedbug based on growers' suggestions. We will look at cultivar preference, the effect of runners, and injury to ripe and green fruit. Research Objective 4: The final set of nutrient management experiments will be carried out during the 2019-2020 season, using a modified experimental design based on research findings from the previous seasons. More in-depth fruit quality analysis (e.g., anthocyanin) of the frozen strawberry fruit sampled from the nutrient management study will also be completed. Research findings from the 2018-2019 season will be presented at professional conferences in 2020. Research Objective 7: At North Carolina A&T State University we will focus on publishing results and an extension guide on organic strawberry production in high tunnels. We also will assess the labor input for organic strawberry production with/without low tunnels in field and high tunnel settings. Research Objective 8: The activities associated with this research objective were completed in April 2019. We will use those results and extend our farmer interviews to investigate farmer decision-making. This will involve a comparison of the motivations and identity of organic, transitioning to organic, and conventional young and new and beginning farmers whose primary production systems are horticultural. Research Objective 9: We plan to conduct one more sensory test to examine how location of purchase affects consumer preference for national and private branded strawberries. This is an important extension of objective 9 considering the divergences in different store features and the fast development of private brands in the grocery sector. We are also developing a survey to investigate the consumer preference for organic strawberries using a national representative sample. Research Objective 10: We plan to prepare technical reports and journal articles based on the economic analysis of cover crop and cultivars. Outreach Objective 1: Our research assessment will be moved to an online platform and we will compare virtual and in-person assessment results. A research assessment will be conducted with strawberry growers in February 2020. We will have one advisory council meeting in spring 2020. Outreach Objective 2: At Florida A&M University, we will continue to improve upon the low-cost crop tunnel technology for growing organic strawberries sustainably. We will develop a fact sheet to promote the use of low-cost crop tunnels for organic production. We will schedule and carry out a sustainable organic strawberry production workshop in January 2020 to share the results of the project with organic growers and other interested groups of farmers. We will continue to develop on the current low-cost crop tunnel design concept to expand on the protective structure capacity to withstand wind loads greater than 30 mph. Efforts to improve on the tunnel structure design to resist greater wind loads would significantly increase the cost of the tunnel hoop materials estimated from $0.50/sq ft using 1-in x 20-ft schedule 40 PVC pipe to $1.20/sq ft for similar size hoops made of galvanized top rail. Thus, it is estimated that the cost of the new hoop material would increase from approximately $141 to $400 per 12 ft x 100 ft tunnel. The material cost to build a low-cost high is $736. Substituting the PVC hoops with galvanized metal hoops would increase the estimated cost to $995. However, switching over to top rail would increase the ability of the low-cost high tunnel structure to resist wind gusts above 30 mph, thereby reducing the effects of wind damage to the structure. Outreach Objective 3: We will hold one Extension training session in February 2020. We will proceed with research results dissemination with a local stakeholder group Florida Organic Growers (FOG). This includes developing and disseminating materials like flyers, fact sheets and videos to upload on our project website. We will present project results to the advisory council and base the development of these materials on their feedback. We will create short video clips demonstrating project results after all data collection has concluded and upload them to our project website. We will hold one field day in January or February 2020 specific to the issue of seed bug in strawberry production systems.

Impacts
What was accomplished under these goals? Research Obj. 1: Sunn hemp ('Tropic Sun') and hairy indigo, and a 4-way mix of sunn hemp ('AU Golden'), hairy indigo, slenderleaf rattlebox, and American jointvetch were compared with a no cover crop control in the main plots of the main on-station trial in Citra, FL. The 4-way mix produced more biomass and had lower light penetration than sunn hemp and hairy indigo, though all cover crops had similar leaf area index. Cover crops did not affect soil health or nematode population. All cover crops reduced broadleaf weed biomass by 70% but had no effect on grasses or sedges. Obj. 2: Four strawberry cultivars were evaluated in subplots after termination of cover crops in the main plots. 'Florida Beauty' (Beauty), 'Florida Radiance' (Radiance), 'Florida127' (FL127), and 'Florida Brilliance' (Brilliance) were planted on Oct. 5, 2018 and data were collected on vegetative growth and fruit yield. Overall, the 2018-2019 season produced 35% higher total marketable fruit yield than 2017, and 43% higher than 2016. 'FL127' and 'Brilliance' produced the highest marketable fruit in 2018-2019. Obj. 3: Spotted wing drosophila (SWD) population was monitored in the main on-station experiment with yeast sugar water traps. Females and males were collected in small numbers and the population peaked at 6.3 females and 1.8 males/trap on Mar. 14. No larval infestation of fruit was detected. Twospotted spider mites (TSSM), other pests, and beneficial arthropods were monitored by collecting leaf samples weekly from Nov. 6 to Mar. 14. The TSSM population peaked at 1452 (mites and eggs)/leaf in 'Beauty' on Feb. 11 compared with 277 in 'Radiance', 697 in 'FL127', and 932 in 'Brilliance' on Feb. 18. Predatory mites were used for managing TSSM. Natural enemies included: sixspotted thrips, spiders, Geocoris sp., Orius sp., and parasitoids. Seed bugs were the main pest observed with no difference among cultivars. Frankliniella bispinosa was the dominant species on flower samples. Obj. 4: On-station, a sunn hemp cover crop, vermicompost, and preplant fertilization vs. in-season fertigation were examined with 'FL127' and 'Brilliance'. A split-split plot design was used with the cover crop and vermicompost treatment combinations as the whole plots, fertilization methods as the subplots, and cultivars as the sub-subplots. Anion exchange membranes and a lab. incubation study were used to monitor soil nitrate nitrogen (NO3-N) availability. Sunn hemp incorporation significantly increased soil NO3-N availability during the first 2 weeks. Shortening the period between sunn hemp incorporation and strawberry planting may reduce N loss and better synchronize N supply with crop uptake. Sunn hemp increased early marketable fruit yield by ~8.5% (p=0.06). Vermicompost also increased marketable fruit yield by ~8% (p=0.06). The biostimulants, Stimplex® and TerraGrow®, were also evaluated with 'FL127' and 'Brilliance' and the combined application of Stimplex® and TerraGrow® increased marketable fruit yield compared to the control. Obj. 5: To detect movement of SWD from adjacent woodlands into a strawberry field at a commercial organic farm, baited traps were deployed at 10-m intervals from the field border into the field as well as 10 m from woodlands areas. More SWD were caught in the woodlands' traps than in the strawberry field. We repeated the trial to compare Grandevo®, Azera®, Veratran DTM, and Entrust® from Mar. 7 to 21 for managing SWD. There were no differences in adult trap catch among treatments and no larvae were collected from fruit samples. Obj. 6: To develop management alternatives for TSSM, spot treatment of N. californicus was compared with whole plot treatment, and a nontreated control. The preventative release of N. californicus did not establish so no difference in TSSM population occurred. Obj. 7: At North Carolina A&T we have completed 2 seasons of field and high tunnel research projects and have been working on journal publications. Two graduate students received their MS degrees from this project. Another graduate student continued the second season of day-neutral strawberry (Albion) soil fertility study. Unfortunately, the plugs provided by the commercial nursery were not conditioned long enough to flower and produce fruit in fall 2018. The trial was terminated in Mar. due to a heavy infestation of anthracnose. Obj. 8: On-farm research was conducted with the same cover crops as in the main on-station trial above and 3 cultivars: 'Brilliance', 'FL127' and 'Radiance'. In Hawthorne, broadleaf weed biomass was reduced by sunn hemp and the 4-way mix compared to hairy indigo, while in Gainesville, there was no effect of cover crops on weed biomass. In Gainesville, 'Brilliance' and 'Radiance' produced 41% higher yield than 'FL127', while in Hawthorne, there was no difference in yield among cultivars. Interviews with the growers to document decision-making processes revealed that future projects must retain on-farm trials to expose on-station treatments to variance, there are a wide variety of farmer practices and management strategies that contribute to the success of an organic strawberry system as a whole, and weather and labor availability were the top 2 challenges for growers. Obj. 9: A sensory taste test was conducted in spring 2019 to evaluate consumer preferences for the 4 cultivars used in the main on-station trial. 'FL127' was the best cultivar in general. 'Beauty' was found to be inferior to the other cultivars in size. The overall taste evaluation indicated that 'Radiance' and 'Brilliance' ranked lower than 'Beauty' and 'FL127', but the difference was not significant. Consumer WTP was highest for 'FL127' with no difference among the other 3 cultivars. Obj. 10: Using partial budget analysis we determined that the net contribution to profit of using a cover crop was unclear. Cover crops contributed to profit in all years on average, but the effect was greatest in 2016. Sunn hemp and the 4-way mix showed potential to increase profits in 2016 ($4000 and $3400 per acre) but their performance declined in 2017 and 2018. 'Brilliance' in 2018 greatly outperformed all other cultivars in all other years. 'FL127' had consistent revenue across all 3 seasons. 'Radiance' performed best in 2017 but worst in 2016. 'Beauty' was the least impressive of the cultivars in terms of revenue. Outreach Obj. 1: Eleven strawberry producers participated in an assessment of the main on-station trial in Feb. 2019 and provided feedback on our research. The most important topics for future research were seed bugs, water conservation methods, alternative mulching practices and continued cultivar and cover crop research to identify best management systems. Two advisory council meetings (Nov. 2018 and Aug. 2019) utilized a panel of 4 organic farmers and one service provider. We provided the council with information and results from our research and the council provided critical feedback. Obj. 2: At Florida A&M, prior to the hurricane Michael on Oct. 10, the project site preparations included a sunn hemp cover crop, soil testing, application of a preplant organic fertilizer, and installation of raised plastic mulch beds. Strawberry plugs were planted on Oct. 12. However, due to post-hurricane rainy weather and limited farm crew labor, the low-cost high tunnels were not erected. Strawberry yield data were collected as open field treatments only. Obj. 3: We conducted 1 training with service providers familiar with organic cropping systems who assessed our research plots and provided feedback. We also held 2 field days to disseminate research results that were attended by 20 participants.

Publications

  • Type: Conference Papers and Presentations Status: Published Year Published: 2019 Citation: Torres-Quezada, E.A. and C. Chase. 2019. Off-season cover crops for organic strawberry production in Florida. American Society of Horticultural Science Annual Conference, Las Vegas, NV.
  • Type: Conference Papers and Presentations Status: Published Year Published: 2019 Citation: Zhao, X. 2019. Cultivar performance and nutrient management in organic strawberry production. Presentation at the invited workshop on organic strawberry production. 9th North American Strawberry Symposium, Orlando, FL.
  • Type: Conference Papers and Presentations Status: Published Year Published: 2019 Citation: Zhao, X., J. Li, Z. Black, and B. Paudel. 2019. Assessing integrated use of cover crop, compost, organic fertilizer, and biostimulant for improving organic strawberry production. 9th North American Strawberry Symposium, Orlando, FL.
  • Type: Conference Papers and Presentations Status: Published Year Published: 2019 Citation: Zhao, X., D. Huff, and Z. Black. 2019. A pilot study of low tunnel strawberry production in Florida. 9th North American Strawberry Symposium, Orlando, FL.
  • Type: Conference Papers and Presentations Status: Published Year Published: 2019 Citation: DeLong, A.N., Swisher, M.E., Sattanno, K., Chase, C., Zhao, X., Liburd, O. & Gao, Z. (2019, July). Co-Creation of Knowledge in Agroecology: Collaborating to Develop Sustainable Organic Agricultural Systems. Paper presented at the American Society for Horticultural Science in Las Vegas, NV.
  • Type: Conference Papers and Presentations Status: Published Year Published: 2019 Citation: Bolques, A., G. Queeley, and F. Ospina. (2019) Assessing the feasibility of growing strawberries organically in a low cost high tunnel. Poster presented at the IX North American Strawberry Symposium, Orlando, FL.
  • Type: Conference Papers and Presentations Status: Published Year Published: 2019 Citation: Bolques, A., G. Queeley, F. Ospina, and V. Richardson. (2019) Low Cost High Tunnel versus Open Field Production of Organically Grown Strawberries in North Florida: Second Year Evaluation. Oral presented at the 132nd Annual Meeting of the Florida State Horticulture Society, Orlando, FL.
  • Type: Conference Papers and Presentations Status: Published Year Published: 2019 Citation: DeLong, A.N., Swisher, M.E., Sattanno, K., Chase, C., Zhao, X., Liburd, O. & Gao, Z. (2018). Enhancing biological research through farmer-driven methods. Poster presented at the Professional Agricultural Workers Conference in Tuskegee, AL.
  • Type: Conference Papers and Presentations Status: Published Year Published: 2018 Citation: Bolques, A., G. Queeley, F. Ospina, and V. Richardson. 2018. Low Cost High Tunnel versus Open Field Production of Organically Grown Strawberries in North Florida. Proc. Fla. State Hort. Soc. 131:106-109.
  • Type: Theses/Dissertations Status: Published Year Published: 2019 Citation: Rentz, J. 2019. Incorporating Revenue Smoothness in Modeling Behavior Under Risk: A Portfolio Selection Approach for Florida Strawberry Producers. MS Thesis, University of Florida.
  • Type: Conference Papers and Presentations Status: Published Year Published: 2018 Citation: Tekan Rana, Sanjun Gu, John Beck, John Kimes and Amy Billard. 2018. Yield and Growth of Organically Managed Day-neutral Strawberries in Low Tunnels within a High Tunnel HortScience 53(9) S89.
  • Type: Conference Papers and Presentations Status: Published Year Published: 2018 Citation: Joshua Mays and Sanjun Gu. 2018. Nitrogen Affects the Growth and Yield of Day-neutral Strawberry Albion in Low Tunnels. HortScience 53(9) S141.
  • Type: Conference Papers and Presentations Status: Published Year Published: 2018 Citation: Amy Ballard, Sanjun Gu, John Kimes, John Beck and Tekan Rana. 2018. Production Potential of Organically Managed June-bearing Strawberry Varieties Grown under High Tunnels and Low Tunnels. HortScience 53(9) S164.
  • Type: Conference Papers and Presentations Status: Published Year Published: 2018 Citation: Amy Ballard, Sanjun Gu, John Kimes, John Beck and Tekan Rana. 2018. Low Tunnels Provided Frost Protection and Increased Yield of Organically Managed June-bearing Strawberries in Field Production. HortScience 53(9) S256.
  • Type: Conference Papers and Presentations Status: Published Year Published: 2018 Citation: Tekan Rana, Sanjun Gu, John Beck, John Kimes and Amy Ballard. 2018. Low Tunnel and Planting Dates Affected Yield and Growth of Organically Managed, Field Grown Day-neutral Strawberries. HortScience 53(9) S311.
  • Type: Conference Papers and Presentations Status: Published Year Published: 2018 Citation: Amy Ballard, Sanjun Gu, Tekan Rana, John Beck and John Kimes. 2018. Frost Protection of Low Tunnels to Organically Managed Strawberries in Field and High Tunnels. HortScience 53(9) S468.
  • Type: Conference Papers and Presentations Status: Published Year Published: 2018 Citation: Tekan Rana, Sanjun Gu, Amy Ballard, John Beck, John Kimes and Jianmei Yu. 2018. Low Tunnels Affect Fruit Quality of Organically Managed Strawberries In Field and High Tunnels. HortScience 53(9) S474.
  • Type: Journal Articles Status: Submitted Year Published: 2019 Citation: Tekan Rana and Sanjun Gu. 2019. Growth and Yield of Organic Day-neutral Strawberries in Low Tunnels inside High Tunnel in North Carolina. HortScience (submitted).
  • Type: Journal Articles Status: Submitted Year Published: 2019 Citation: " Tekan Rana, Sanjun Gu and Jianmei Yu. 2019. Effect of Low Tunnels and Planting Dates on the Fruit Quality of Organic Day-Neutral Strawberries in High Tunnels in North Carolina. International Journal of Fruit Science (Submitted).
  • Type: Conference Papers and Presentations Status: Published Year Published: 2019 Citation: Li, J., X. Zhao, G. Maltais-Landry, B.R. Paudel, and Z. Black. 2019. Influence of integrated nutrient management on nitrogen availability and organic strawberry production. American Society for Horticultural Science Annual Conference, Las Vegas, NV.
  • Type: Conference Papers and Presentations Status: Published Year Published: 2019 Citation: Li, J., X. Zhao, B.R. Paudel, and Z. Black. 2019. Exploring the use of seaweed biostimulant in organic strawberry production. American Society for Horticultural Science Annual Conference, Las Vegas, NV.
  • Type: Conference Papers and Presentations Status: Published Year Published: 2019 Citation: Rhodes, E. M., C. A. Chase, X. Zhao, and O. E. Liburd. 2019. Spotted wing drosophila spatial distribution and movement on an organic strawberry farm in Florida. Entomological Society of America Southeastern Branch annual meeting. Mobile, Alabama 3-6 March 2019.
  • Type: Other Status: Published Year Published: 2019 Citation: DeLong, A.N., Swisher, M.E., Sattanno, K., Chase, C., Zhao, X., Liburd, O. & Gao, Z. (2019, February). Sustainable organic strawberry cropping systems for the Southeast. Workshop presented at the North American Strawberry Symposium in Orlando, FL.


Progress 09/01/17 to 08/31/18

Outputs
Target Audience:UF The target audience included: certified organic strawberry growers, growers transitioning to organic production, service providers, stakeholders, Extension personnel, and researchers. Results were presented to researchers and Extension personnel attending the meetings of the American Society for Horticultural Science (ASHS), Tri Societies (ASA, CSSA, and SSSA), Florida Entomological Society, Florida State Horticultural Society (FSHS), Entomological Society of America Southeastern Branch, and Entomological Society of America. Florida A&M University (FAMU) The target audiences reached during this reporting period were organic farmers including small farm and urban farmers from Gadsden, Leon, Jefferson, and Wakulla Counties in North Florida and Thomas and Grady Counties in South Georgia who attended a spring field day and a fall annual field day at the FAMU Research and Extension Center in Quincy, FL. Results were also shared with attendees of the FSHS meeting. North Carolina A&T State University (NC A&T) The target audiences were small farmers who are interested in growing organic strawberries in both field and protected production systems and selling strawberries in direct markets, extension educators and other agricultural professionals who work with strawberry and high tunnels, and the general public with an interest in strawberry and local food production. Results were also presented to researchers attending annual meetings of ASHS and the Southern Region ASHS. Changes/Problems:Plant disease management continued to be a major problem during the organic strawberry production season especially when conducive weather conditions were present and persistent. A variety of biological fungicides and other products approved for organic production were used during the harvest season to maintain plant health. A more integrated program will be implemented in the coming season to better overcome the disease management challenge. Given the weed pressure encountered in the nutrient management trial, a field with relatively low levels of weed infestation will be selected if possible for the nutrient management study during the 2018-2019 season. A major change to the arthropod monitoring in the main on-station experiment will be to focus solely on the effect of strawberry cultivar since there has been no significant effect of the summer cover crop. The lack of significant results in the SWD efficacy trial was likely due to the 14-day application interval. A 7-day application interval will be used this coming season. Also, the label rate of Entrust for strawberries has increased and this new, higher label rate will be used this coming season. In addition, much higher numbers of SWD were caught in traps in the North end of the experimental plot, so the arrangement of blocks will be modified accordingly. The main issue with the site-specific predatory mite release trial was a very uneven distribution of TSSM in the experimental plots. This is a common issue as TSSM is known to have a patchy distribution. The treatments will be re-randomized this season to minimize this effect. The TSSM efficacy trial was not repeated because the plot that was going to be used for both this experiment and some seed bug research was only used for the seed bug research to avoid impacts of the miticides on the seed bugs. By the time this decision was made, it was too late to make a separate plot to repeat the TSSM efficacy work. Because of unexpected low yield from the field trials in 2017-2018 season, the sensory test and experimental auction could not be conducted due to insufficient strawberry fruits. We plan to conduct the sensory test and experimental auction at multiple 2018-2019 times during the season instead of trying to predict a peak yield time in February or early March of 2019. We plan to improve on the low-cost high tunnel design so that tunnels can withstand wind loads greater than 30 mph. Design changes to the tunnel structure will considerably increase the cost of the hoop materials estimated from $0.50/ft2 for 1-in x 20-ft schedule 40 PVC pipe to $1.20/ ft2 for 1.31 x 10.5-ft galvanized top rail. This will increase the cost of the hoop material from approximately $141 to $400. Currently the cost of a low-cost high tunnel is $736. Substituting the PVC pipe with galvanized top rail would increase the cost to $995. Switch over to top rail should increase the ability of the structure to resist wind gusts above 30 mph. Therefore, we plan to include a top rail high tunnel during the 2018-2019 season. What opportunities for training and professional development has the project provided?Students/postdoctoral/visiting scientist Graduate students, undergraduate students, and postdoctoral research associates have been involved in the project. A visiting professor from China also participated in the research trials in Citra, FL learning about the organic strawberry production systems. Workshops, Field Days, Training, Conferences At the University of Florida, we provided one training with service providers familiar with organic cropping systems. Local service providers assessed our research plots and provided feedback on our research. Certified Crop Advisors could receive up to three Continuing Education Units (CEUs) for their participation. Graduate students presented research results at the TriSocieties Meeting in 2017 and at the Florida State Horticultural Society (FSHS) and American Society for Horticultural Science (ASHS) in 2018. The North Carolina A&T group presented the strawberry research results at a few professional conferences, a training and a seminar. 2017 American Society for Horticultural Science (ASHS) conference. September 19-22, 2017. The Big Island of Hawaii. Two posters from this grant. Invited seminar at Purdue University. Organic Strawberry Research at NC A&T. November 9, 2017. 2018 Southern Region ASHS conference. February 2-4 2018. Jacksonville, FL. Two oral presentations from this grant. 2018 ASHS Conference. July 30-August 2. Washington, D.C. Three oral presentations and two poster presentations from this grant. Southern Region Small Fruit Consortium Training. 2018.7.19. Hendersonville, NC. Dr. Bolques and two other Florida A&M University project participants attended the FSHS meeting where Dr. Bolques presented the results of the 2016-2017 low-cost high tunnel demonstration trial. How have the results been disseminated to communities of interest?UF: Field research assessment of the organic strawberry cultivar evaluation trial was conducted during the production season. Research findings were presented at the ASA, CSSA & SSSA International Annual Meetings in fall 2017, at the Florida State Horticultural Society meeting, and at the American Society for Horticultural Science meeting. FAMU: Dr. Bolques presented the results of the 2016-2017 low-cost high tunnel demonstration trial at the NC A&T: We presented the strawberry research results to a few grower conferences at the state, county or regional levels. Southeast Strawberry Expo. November 1-3, 2017. Wilmington, NC. CFSA Sustainable Agriculture Conference. November 1-3, 2017. Durham, NC. The annual Small Farms Week. March 26-30, 2018. Greensboro, NC. Winter strawberry field day. March 27, 2018. What do you plan to do during the next reporting period to accomplish the goals?Research Objective 1 We will complete the third and final field season to evaluate cropping system combinations of summer cover crops and strawberry cultivars. Analysis of the performance of the cover crops over the three years be conducted to compare their effects on weed and nematode suppression and on soil health. Research Objectives 2 and 4 Fruit quality assessment including soluble solids content and titratable acid and data analysis will be completed for the strawberry cultivar evaluation trial. More in-depth fruit quality analysis (e.g., anthocyanin and total phenolic contents) of the frozen strawberry fruit sampled from the nutrient management study will also be completed. Research findings from the 2017-2018 season will be presented at professional conferences in 2019. Both the organic strawberry cultivar evaluation trial and the nutrient management experiment will be continued during the 2018-2019 season, with modifications made to the experimental design according to the research results from the previous season. Research Objectives 3, 5, and 6 Arthropod monitoring in the main on-station trial (Objective 3) will be repeated in the upcoming season. Since there are now two years of data showing that cover crops have no effect on the various arthropod populations monitored, the focus will be on cultivar effects only. The SWD movement experiment will be repeated at the same organic farm to confirm the results. Additional traps may be added spaced farther into the strawberry field. The SWD efficacy trial and site-specific predatory mite trials will also be repeated. The student responsible for the TSSM efficacy trial is graduating, so this experiment will not be repeated in 2018-2019. However, work on evaluating the injury and susceptibility of strawberry cultivars to the strawberry seed bug will be conducted instead by another graduate student. Arthropod monitoring on the two organic farms will also be repeated if desired by the cooperating growers. Research Objective 7 The field research at NC A&T has been completed. This current year the focus will be on completing the data analysis and journal manuscript preparation. Research Objective 8 We will continue conduct a second year of participatory on-farm field trials at two local farms. We will capture photos of the research process regularly throughout the production season in order to create a video demonstrating field trial results. The videos will consist of photomontages alongside interviews with PIs. The video will be uploaded to a website accessible to the public. We will analyze farmer notes and records to qualitatively assess on-farm decision-making processes. Research Objective We will conduct the sensory tests and experimental auctions in the early season of 2018-2019. For example November 2018 to January 2019 multiple times in a longer time period to make sure enough participants can be recruited to avoid the unexpected low yield in February or early March of 2019. Research Objective 10 Partial budget analysis will be conducted using the 2017 field trial data. Based on the discussions at the advisory board committee meeting, we will incorporate the market risk (price volatility at different season of the year) into future analysis. Outreach Objective 1 Industry Liaison Panel We will hold our third industry liaison panel meeting in fall 2018. This meeting will focus on conveying results from our project to-date with our panel of members from Florida, South Carolina and North Carolina. We will recruit another member from Georgia to join our panel. Panel members will provide feedback on our project results, goals and objectives to inform future decisions. Liaison panel members will be encouraged to co-host and/or participate in field days and trainings. Outreach Objective 2 At Florida A&M University we will continue to improve low-cost high tunnels for growing organic strawberries sustainably. We will publications to promote the use of low-cost high tunnels for organic production. We will continue to offer training on how to construct low-cost high tunnels for organic strawberry crop protection. Outreach Objective 3 At the University of Florida, we will hold an in-service training and research assessment aimed at Extension agents and service providers at the Plant Science Research and Education Unit (PSREU) in Citra, which will be the third year of on-station assessments. The assessment is conducted in two parts. First, participants assess our field plots. Second, we have a group discussion about the participants' observations to ultimately come up with recommendations for future research design. There will be two groups, one of growers and one of service providers. Outreach to extension providers and current and potential organic strawberry growers will also include two on-farm field-days that will allow interaction with the research faculty and farmers conducting on-farm trials. Instead of a workshop at the Florida State Horticultural Society meeting in June 2018, we will host our workshop instead at the 9th North American Strawberry Symposium (NASS) and North American Strawberry Growers Association (NASGA) 2019 Conference in February 2019. At North Carolina A&T an extension guide on organic strawberry production in high tunnels will be developed.

Impacts
What was accomplished under these goals? Research Objective 1 Cover crop treatments (1) Crotalaria juncea cv. Tropic Sun, (2) Indigofera hirsuta, and (3) a 4-way mixture of Aeschynomene americana, C. juncea cv. AU Golden, C. ochroleuca, and I. hirsuta were compared with a weedy control in summer 2017 in the main trial at the Plant Science Research and Education Unit (PSREU). Data were collected on cover crop height, cover crop and weed population densities and biomass, plant pathogenic nematode populations, leaf area index and photosynthetically active radiation penetrating the cover crop canopy, and soil health. Research Objective 2 SensationTM Brand 'Florida 127', 'Florida Radiance', and WinterstarTM 'FL 05-107' were again evaluated, while 'Florida Beauty', replaced 'Strawberry Festival'. Jiffy plug transplants were planted in Oct. 2017 and harvested from Nov. 2017-Apr. 2018. 'Florida Beauty' plants were smallest in size and consistently flowered and fruited earliest. However, full-season marketable yield per plant was lowest with 'Beauty', while yields of 'Florida 127' and 'Radiance' were greater than the other two cultivars. The cover crop treatments did not impact strawberry marketable yield. Research Objective 3 Spotted wing drosophila (SWD): Scentry traps were used to monitor the main trial. Few female SWD and no males were caught prior to Mar. The female population peaked at 11.5 ± 4.2/trap and males peaked at 1 ± 0/trap on 12 Mar. No larvae were detected. Twospotted spider mites (TSSM), other pests and beneficials: TSSM and eggs began to increase on 19 Dec. 2017, were very high from 8 Jan. until 12 Feb. 2018, and then declined. At the high population period, more TSSM and eggs were noted on 'Beauty' than on the other cultivars. Neoseiulus californicus predatory mites (PM) were released at a preventative rate in Nov. 2017 and at a curative rate in Jan. 2018. Phytoseiulus persimilis PM were released at a curative rate mid-Feb. The PM population was low until 16 Jan. 2018, peaked on 12 Feb., then declined to low levels after 19 Feb. PM population was highest on 'Beauty' and more PM eggs were observed on 'Beauty' than on 'Radiance' and 'FL 05-107'. Data were also collected on other pests and beneficials. Research Objective 4 This field trial at PSREU utilized a split-split plot design. The whole plots consisted of combinations of sunn hemp (no cover crop vs. sunn hemp seeded at 44.9 kg/ha) and compost (0, 22.4, 44.8 t/ha) treatments, and the subplots were fertilization treatments, with the use of Stimplex biostimulant in the sub-sub plots. There were four fertilization treatments based on nitrogen (N) application: 0, 84 kg/ha at preplant, 160 kg/ha in-season fertigation, and preplant plus in-season fertigation. Anion exchange membranes were successfully used to monitor plant-available N dynamics, but will need further validation. The effects of the treatments on strawberry yield and quality of 'Florida 127' were determined. Research Objective 5 Movement: Assessing SWD movement from adjacent woods to an on-farm strawberry field employed Scentry traps: on the edge of the woods, 5 m outside the strawberry field, and at 5, 10, 20, and 40 m into the field. The results support movement of SWD from the woods to the field. Evaluation of OMRI-approved products: Azera®, Entrust®, Grandevo®, and Veratran DTM were evaluated at label rates on 9 and 23 Mar. in a small field planted with 'Festival' strawberries at PSREU. There was no difference among treatments in adults per trap. Only a single larva was collected. Research Objective 6 Site-specific treatments: This trial was conducted in the same small 'Festival' strawberry field as the SWD pesticide efficacy trial. Treatments included: (1) N. californicus PM released at the preventative rate of 25 per m2 on 16 Nov. 2017, (2) N. californicus PM were released over the entire plot and (3) spot treatment - predatory mites released onto 5 groups of 8 plants on 11 Jan. 2018 at the rate of 1 predatory mite/1 TSSM, and (4) a nontreated control. Only the preventative treatment resulted in fewer TSSM mites and eggs than the control. Research Objective 7 In each of two 30-ft x 96-ft high tunnels, three low tunnels (LT) were installed, with the other beds as controls (NLT). One high tunnel was used for June-bearing strawberry cultivars (Benicia, Camino Real, Radiance and FL 05-107) and the other for day-neutral cultivars (Albion and San Andreas, which were transplanted on two dates - D1, first week of Sep. and D2, last week of Sep.). Low tunnel performance was also assessed in an open field production system. Day-neutral: The LT and D1 increased total and marketable yields. Low tunnels shortened days to 50% bloom by 7 days. Low tunnels reduced frost damage to open blooms and fruit, and increased fruit dry biomass, but had no effect on fruit quality. Thus, LT and D1 are recommended in high tunnels for organic production of day-neutral strawberry cultivars. June-bearing: Marketable yield was 230 g/plant with LT and 255 g with NLT. 'FL 05-107' (274 g/plant) had the highest marketable yield, followed by 'Radiance' (247), 'Camino Real' (239) and 'Benicia' (212). In Feb. 2017 frost damage to flowers was higher with LT (27%) compared to NLT (8%) due to more flowers being present at sampling. In Jan. 2018 frost damage to flowers was lower with LT (72%) than with NLT (83%). Low tunnels inside high tunnels may not be an economically feasible option for June-bearing strawberries. Field/low tunnel trials: Preliminary results indicated that LT increased marketable yields of organic strawberries by protecting plant, flowers and fruit from cold damage. Research Objective 8 On-farm research trials were initiated on 2 organic farms in Jul. 2017. The farmers participated in the selection of treatments. The split-plot design has whole plot treatments of (1) C. juncea cv. Tropic Sun, (2) I. hirsuta, and (3) the 4-way mix of A. americana, C. juncea cv. AU Golden, C. ochroleuca, and I. hirsuta. 'Radiance', 'Florida 127', and 'Beauty' were evaluated in subplots. Data were collected on cover crop and strawberry cultivar performance, arthropod pests, plant pathogenic nematodes, weeds, and soil health. The farmers were interviewed to document their decision-making processes. Research Objective 9 The instrument and procedure for the sensory test and experiment auction were finished in spring 2018. IRB review for the test has also been approved. The sensory test and experiment auction were not conducted due to insufficient fruits from the field trial. Research Objective 10 Partial budget analysis was used to compare the cost and benefit of the 3 cover crop treatments used in the 2016 field trial at PSREU. The C. juncea and the 4-way mix treatments increased profits relative to the no-cover-crop control while the I. hirsuta treatment decreased yield and thus decreased profits relative to the control. A sensitivity analysis and a break-even analysis were also performed. Outreach Objectives Meetings of the Industry Liaison Panel and a research assessment of the main on-station experiment with local strawberry producers and service providers provided feedback regarding what they liked about our research, what they disliked, and considerations for the future. The feedback was used to modify our research design for the 2018-2019 strawberry production season. The feasibility of low-cost high tunnels for organic strawberry production contiued at the FAMU Research and Extension Center in Quincy, FL. Four strawberry cultivars were grown in 12-ft x 100-ft plots consisting of an open-field area and another two areas protected by 12-ft x 100-ft low cost crop tunnels following a C. juncea cover crop.

Publications

  • Type: Conference Papers and Presentations Status: Published Year Published: 2017 Citation: Ahuja, P., X. Zhao, C.A. Chase, O.E. Liburd, E. Rhodes, M.E. Swisher, A. DeLong, and L. Khandaker, 2017. Strawberry Cultivar Assessment for Organic Production Systems in Florida. ASA, CSSA & SSSA International Annual Meetings, Tampa, FL.
  • Type: Conference Papers and Presentations Status: Published Year Published: 2017 Citation: Ballard, A. and S. Gu. 2017. Production of Organically Managed June-bearing Strawberries in Low and High Tunnels. HortScience 52(9) S332.
  • Type: Conference Papers and Presentations Status: Published Year Published: 2018 Citation: Bolques, A., G. Queeley, F. Ospina, and V. Richardson. 2018. Low Cost High Tunnel versus Open Field Production of Organically Grown Strawberries in North Florida. Florida State Horticulture Society Annual Meeting. Fort Lauderdale, FL.
  • Type: Conference Papers and Presentations Status: Published Year Published: 2017 Citation: Chase, C.A, P. Ahuja, M.E. Swisher, X. Zhao and O.E. Liburd. 2018. Size Matters: Sunn Hemp Cultivar Choice Influences Companion Species Biomass Production in a Cover Crop Mixture. ASA, CSSA, and SSSA Annual Meeting. Tampa, Florida.
  • Type: Conference Papers and Presentations Status: Published Year Published: 2017 Citation: DeLong, A., M.E. Swisher, C. Chase, C., X. Zhao, K. Sattanno, E. Rosskopf, F. Di Goia, and J. Hong. 2017. Participatory Methods in Crop Research: Giving More Decision-making Power to Farmers. ASA, CSSA, and SSSA Annual Meeting. Tampa, Florida. https://scisoc.confex.com/crops/2017am/webprogram/Paper108860.html
  • Type: Conference Papers and Presentations Status: Published Year Published: 2018 Citation: DeLong, A., Swisher, M.E., Sattanno, K., Chase, C., Zhao, X., Liburd, O. and Gao, Z. 2018. Social Science in Service to Biological Research. Oral presentation. Florida State Horticultural Society Annual Meeting, Fort Lauderdale, Florida.
  • Type: Conference Papers and Presentations Status: Published Year Published: 2017 Citation: Gu, S. 2017. High Tunnel Temperatures--Characteristics and Management Strategies. HortScience 52(9) S95.
  • Type: Conference Papers and Presentations Status: Published Year Published: 2017 Citation: Gu, S. T. Rana, J.E. Beck, and J.E. Kimes. 2017. Production of Day-neutral Strawberry in Organically Managed High/Low Tunnels. HortScience 52(9) S332.
  • Type: Conference Papers and Presentations Status: Published Year Published: 2018 Citation: Rentz, J.E., Z. Gao, X. Zhao, C.A. Chase, Z. Black, O.E. Liburd, M.E. Swisher. 2018. Economic Feasibility of Cover Crops for Organic Strawberry Production. ASHS Annual Meeting, Washington DC. https://ashs.confex.com/ashs/2018/meetingapp.cgi/Paper/29122.
  • Type: Conference Papers and Presentations Status: Published Year Published: 2018 Citation: Rhodes, E.M., C.A. Chase, X. Zhao, and O.E. Liburd. 2018. Ecology and Management of the Twospotted Spider Mite, Tetranychus urticae, in Organic Strawberries in Florida. Florida Entomological Society Annual Meeting, St. Augustine, FL. July 23  25, 2018.
  • Type: Conference Papers and Presentations Status: Published Year Published: 2018 Citation: Rhodes, E.M., C.A. Chase, X. Zhao, and O.E. Liburd. 2018. The Effect of Cover Crop and Variety on Twospotted Spider Mites, Tetranychus urticae, and Its Natural Enemies in Organic Strawberries. Entomological Society of America Southeastern Branch Annual Meeting, Orlando, FL. March 3  7, 2018. https://esa.confex.com/esa/2018seb/meetingapp.cgi/Paper/129229
  • Type: Conference Papers and Presentations Status: Published Year Published: 2017 Citation: Rhodes, E.M., C.A. Chase, X. Zhao, and O.E. Liburd. 2017. Spotted Wing Drosophila Monitoring and Distribution on Organic Strawberries in Florida. Entomological Society of America Annual Meeting. Denver, CO. Nov. 5  8, 2017. https://esa.confex.com/esa/2017/meetingapp.cgi/Paper/125021


Progress 09/01/16 to 08/31/17

Outputs
Target Audience:University of Florida The target audience includes: certified organic strawberry growers, service providers, stakeholders, Extension personnel, agricultural consultants, researchers, industry representatives, and the general public. For the on-farm research and outreach objectives, our target audience is primarily comprised of two different groups. One target audience is local organic strawberry producers. The second target audience is local service providers that work with strawberry producers. Our research matters to these two groups as the primary users and future adopters of the technologies we are developing. We value input from end-users in order to maximize technology adoption rate. The target audience for the economic research is: strawberry growers, strawberry retailers, researchers working on sustainable strawberry production. Florida A&M University The target audience reached during this reporting period included organic farm producers. Others participating included small farm and urban farm producers as well as Annual Field Day participants from Gadsden, Leon, Jefferson, and Wakulla Counties in North Florida and Thomas and Grady Counties in South Georgia. While the majority of our clientele are African American, an ethnically diverse clientele benefits from the Florida A&M University Extension/Research and Extension Center educational opportunities. North Carolina A&T State University For the work in North Carolina, the target audiences are small farmers who are interested in growing organic strawberries in both field and protected production systems, and selling strawberries in direct markets. Changes/Problems:Some strawberry plants significantly declined following field transplanting in the main on-station trial and had to be replanted due to the confounding effects of irrigation issue and soil-borne pathogen problem. Root dipping with Actinovate AG biological fungicide was conducted during replanting to help protect the plants, while irrigation was more carefully monitored to avoid water stress to plants. High weed pressure was encountered in the nutrient management experiment field, which might have interfered with the nutrient management treatments. A better weed management plan will be implemented during the 2017-2018 season. With the arthropod studies there were three problems. The first was that the area used for evaluating OMRI-approved products for managing SWD was too small. In the upcoming season, we are going to plant a larger area that will allow each replication to consist of 5 small plots of strawberries rather than 5 single rows. The second problem was that the TSSM population was too low to conduct the experiment on site-specific placement of predatory mites. Having a separate site for evaluating OMRI-approved products for managing SWD will give us a second location to conduct the experiment if the TSSM population in the main on-station experiment is again low. Since it will be a separate site, the naturally occurring population of TSSM could be increased by inoculating plants with mites from a lab colony if necessary. The third problem was that the mite population in the small site used for evaluating OMRI-approved products for managing TSSM was too low to justify the application of chemicals. Even introducing spider mites did not help the population build up. Therefore, the experiment was carried out near the end of the season and environmental conditions such as temperature may have influenced the results. The low cost crop tunnel design will be improved so that the structures can withstand wind speeds greater than 30 mph. What opportunities for training and professional development has the project provided?Outreach Objective 1: We will engage producer and county Extension faculty members in research and outreach planning, implementation and outcomes We conducted a research assessment of the main on-station experiment with strawberry producers. Local strawberry producers and service providers assessed our research plots and provided feedback regarding what they liked about our research, what they disliked, and what was missing that we should consider in the future. We used feedback from the research assessment to modify our research design for the 2017-2018 strawberry production season. Specifically, we eliminated one strawberry cultivar, Strawberry Festival, which was generally disliked by strawberry producers. By integrating end-user feedback, we contribute to expediting technology adoption in agriculture. Outreach Objective 2: We will demonstrate the feasibility of organic strawberry production in low cost crop tunnels Four strawberry cultivars (Strawberry Festival, Florida Radiance, WinterstarTM, and Sensation™) were grown using organic methods at the Florida A&M University Research and Extension Center in Quincy, FL either in an open-field system or within a low cost crop tunnel crop production system during Fall 2016 through mid-Spring 2017. The preliminary analysis of the yield data suggests that fruit weights of the four cultivars evaluated were higher in the low cost crop tunnel than in the open field. Outreach Objective 3: We will provide Extension faculty members, other local service providers, and growers with research results and recommendations We conducted one training with service providers familiar with organic cropping systems. Local service providers assessed our research plots and provided feedback regarding what they liked about our research, what they disliked, and what was missing that we should consider in the future. Students/postdoctoral Both graduate and undergraduate students have been involved in the project at the University of Florida (UF) and at North Carolina A&T State University. At UF, graduate students have been trained on procedures for social and economic research. For example, students have completed IRB training for human subject-related research, and learned to develop instruments for questionnaires and spreadsheet template for budget analysis of production systems. Dr. Preeti Ahuja (post-doctoral research associate) has participated in the following training opportunities and workshops: Training on "SAS Statistical Software" by Prof. Edzard van Santen, Agronomy Department, University of Florida, Gainesville from January 10, 2017 to February 01, 2017. Workshop on "New Refworks" at the University of Florida, Gainesville, on January 25, 2017. Workshop on "Author's Rights & Responsibilities: Understanding Copyright & Open access in Modern Scholarly Publishing" at University of Florida, Gainesville, on February 1, 2017. Completed Collaborative Institutional Training Initiative (CITI) program on 'Responsible Conduct of Research' on February 2, 2017. Participated in a workshop on "How to Publish" at University of Florida, Gainesville on March 31, 2017. The group at North Carolina A&T State University presented the strawberry research results at several professional conferences: Sanjun Gu, John E. Beck and Joseph A. Moore. 2016. Including Low Tunnels in a High Tunnel for Winter Strawberry Production in Cold Hardiness Zone Seven. American Society for Horticultural Science conference, Atlanta, GA. Sanjun Gu, John E. Beck and Joseph A. Moore. 2016. Organic Strawberries in High Tunnels: Cultivar Selection and Economics. The 7th National Small Farm Conference. Virginia Beach, VA. Sanjun Gu. Performance of ten strawberry cultivars in organically managed high tunnels in North Carolina. The 18th Association of 1890 Research Directors, Inc. (ARD) Biennial Research Symposium. April 1-4, 2017. Atlanta, GA. Sanjun Gu. Characterizing high tunnel and low tunnel microclimates in North Carolina. The 18th ARD Biennial Research Symposium. April 1-4, 2017. Atlanta, GA. How have the results been disseminated to communities of interest?Florida Field research assessment of the organic strawberry cultivar evaluation trial was conducted during the production season. Some of the cultivar assessment information was presented at the Florida A&M University High Tunnel Workshop. Liburd O.E. 2017. Presentation on monitoring for SWD in small fruit crops. Several examples were taken from the strawberry production system. Southeastern Branch, Entomological Society of America, Memphis Tennessee. A workshop on High Tunnels was offered in the Spring of 2017 that provided participants with information on the Pros and Cons of High Tunnels, Site Prep and Crop Selection for High Tunnels, Hot Pepper and Strawberry Production Results in a Low Cost High Tunnel, Conservation Biocontrol of Insect Pest, Enhancing Natural Enemies in High Tunnels, High Tunnel Cost Sharing Opportunities, High Tunnel Growers Resources and Supplies, and a hands-on activity on How to Construct a low cost high tunnel. North Carolina Gu, S. et al. High Tunnel Workshop Series. Six workshops on high tunnel production and marketing. Oct. 2016 to Mar. 2017. Gu, S. and J. Beck. 2016 High tunnel research updates. 2017 Small Farm Week. March 22, 2017. Gu, S. High tunnel advanced topics. 2017 Orange County Ag. Summit. February 20, 2017. Gu, S. Season extension with high tunnels. Vance County vegetable symposium. February 15, 2017. Gu, S. The benefits of using high tunnels. 2017 Delaware Ag. Expo. January 11, 2017. Gu, S. High/low tunnel strawberry research update. 2017 SE Regional Fruit & Vegetable Conference and Tradeshow. January 7, 2017. Savannah, GA. Gu, S. High tunnel and season extension. Tri-county Ag. Expo. Dec. 6, 2016. Cherokee/Marble, NC. Gu, S. Getting started with high tunnels. NC State Extension Conference. Nov. 2016. Raleigh, NC. What do you plan to do during the next reporting period to accomplish the goals?Research Objective 1: Assess the Efficacy of Off-season Cover Crops on Soil Health and in Suppressing Weeds, Sting Nematodes, Arthropod Pests, and Pathogens The main on-station trial will be repeated with cover crops to be reestablished in summer 2017 within the same whole plots as for 2016. This will allow us over the life of the project to compare the cumulative effects of the cropping systems. Research Objective 2: Evaluate the Performance of Strawberry Cultivars in Open Field Organic Production Systems Four strawberry cultivars will again be evaluated within the subplots of the main on-station trial. However, based on stakeholder research assessment 'Strawberry Festival' will be replaced. Research Objective 3: Monitor Population of Arthropod Pests, Including the Spotted Wing Drosophila (SWD) and Twospotted Spider Mite (TSSM), and Beneficials Monitoring will be repeated in the main on-station trial to improve our understanding of the effects of the cropping systems on pest and beneficial arthropods. Research Objective 4: Integrate Summer Leguminous Cover Crop into Nutrient Management Program for Organic Strawberry Production Systems More in-depth fruit quality analysis (e.g., total phenolic content) of the frozen strawberry fruit sampled from the nutrient management trial will be completed. The nutrient management experiment will be repeated during the 2017-2018 season with slight modifications made to the experimental design according to the research results from the previous season. Research Objective 5: Develop Pest Management Practices for Spotted Wing Drosophila We will repeat the study on SWD movement either in the main on-station experiment or at a commercial organic farm. Results from the 2016-2017 study will be presented at the 2017 Entomological Society of America Annual Meeting in Denver, CO from 5 - 8 Nov. 2017. The evaluation of OMRI-approved products for SWD management will be repeated in a separate strawberry plot within the organic area at the research station. Research Objective 6: Develop Management Alternatives for Twospotted Spider Mite The study of site-specific treatments with the predatory mites, Neoseiulus californicus, will be repeated in a separate strawberry plot within the organic area at the research station. The evaluation of OMRI-approved products for TSSM management will be repeated in a separate strawberry plot within the organic area at the research station. The treatments will be applied early in the season in order to have at least two applications during the season. Research Objective 7: Assess the Season Extension Potential of Low and High Tunnels in Organic Strawberry Production The 2017-18 research will begin in September 2017. Research will be conducted as originally planned. Research Objective 8: Farmer assessment of response of cover crop and cultivars to on-farm bio-physical and management regimes During the next reporting period, we will work toward Farmer Field Trials, Industry Liaison Panel & Research Assessments, and Workshops, Field Days, Training. Participatory on-farm field trials were initiated in July 2017 at two local farms. We will capture photos of the research process regularly throughout the production season in order to create a video demonstrating field trial results. The videos will consist of photomontages alongside interviews with PIs. The video will be uploaded to a website accessible to the public. We will analyze farmer notes and records to qualitatively assess on-farm decision-making processes. Research Objective 9: Evaluate consumer preferences for traditional and recently released strawberry cultivars with regard to sensory attributes like flavor, color, and texture, including consumer willingness to pay An experimental plan will be developed for the sensory study that will be conducted in November and December. Research Objective 10. Calculate Production Costs and Potential Returns of Selected Management Alternatives Based on Data from the Biological Research We plan to collect economic data on inputs used in strawberry production and yield from on-station trials. Prices of inputs and outputs will be collected based on publically available data (USDA, publication on budget analysis of strawberries) and staff managing the on-station trials. A partial budget analysis will be conducted to compare the economic return from different strawberry cultivars as well as different production system (cover crops). Outreach Objective 1: We will engage producer and county Extension faculty members in research and outreach planning, implementation and outcomes Industry Liaison Panel and Research Assessments We will assemble an industry liaison panel in fall 2017 consisting of strawberry industry leaders who previously agreed to participate in our study, plus team member recommendations. We will hold two meetings. One will occur before our 2018 research assessments and one before our Extension workshop (below) where the panel will suggest guidance for project activities. The research assessment in 2018 will focus on nutrient delivery systems. The assessment is conducted in two parts. First, participants assess our field plots. Second, we have a group discussion about the participants' observations to ultimately come up with recommendations for future research design. Liaison panel members will be encouraged to co-host and/or participate in field days and trainings. Outreach Objective 2: We will demonstrate the feasibility of organic strawberry production in low cost crop tunnels We will continue to improve upon the feasibility of growing organic strawberries sustainably using low cost crop tunnels. We will develop a factsheet to promote the use of low cost crop tunnels for organic production. We will continue to offer training on constructing a low cost high tunnel for organic strawberry crop protection. Outreach Objective 3: We will provide Extension faculty members, other local service providers, and growers with research results and recommendations We will hold an in-service training aimed at Extension agents and service providers at the Plant Science Research and Education Unit (PSREU) in Citra, FL on the topic of advantages and disadvantages of adopting organic strawberry systems.

Impacts
What was accomplished under these goals? Main open-field experiment (Florida) Cover cropping. The first season of the main on-station organic strawberry production system study was initiated in Jul. 2016 in a certified organic field in Citra, FL. Three cover crop treatments (1) Crotalaria juncea cv. Tropic Sun, (2) Indigofera hirsuta, and (3) a 4-way mix of Aeschynomene americana, C. juncea cv. AU Golden, C. ochroleuca, and I. hirsuta were compared with a weedy control in the whole plots of a split-plot design. Whole plot treatments were arranged in a randomized complete block design with four replications. Data were collected on cover crop height, cover crop and weed population densities and biomass, plant-pathogenic nematode populations, leaf area index and photosynthetically active radiation penetrating the cover crop canopy. Crotalaria juncea cv. Tropic Sun produced the most above ground biomass. The biomass produced by the mix and I. hirsuta did not differ significantly. All cover crops suppressed weed biomass. Cultivar evaluation. Following the cover crops, four strawberry cultivars (Sensation™ brand Florida127, WinterstarTM FL 05-107, Florida Radiance, and Strawberry Festival) were evaluated in subplots. Containerized strawberry transplants were planted within the whole plots on 13 Oct., 2016. Plant parameters, leaf number, canopy size and crown diameter, and leaf chlorophyll content index, were measured. Marketable and unmarketable fruit numbers and weights were recorded twice per week. For most of the growth parameters, Winterstar™, Sensation™, and 'Festival' performed better than 'Radiance'. Crotalaria juncea, cover crop mix, and I. hirsuta increased marketable fruit number in Dec.; with little influence of cover crops during the rest of the season. 'Festival' had more marketable and total fruit number, which was not significantly different from WinterstarTM throughout the season; whereas Sensation™ exhibited larger fruit size. WinterstarTM had higher cull fruit weight than other cultivars because of its susceptibility to Botrytis cinerea and Colletotrichum acutatum. No significant difference in soluble solids content, titratable acidity, and pH among treatments was observed. Pest and benefical arthropod monitoring. Spotted wing drosophila (SWD) adults were monitored using traps and larvae by collecting weekly fruit samples. Female SWD were present throughout the season with a peak in population in mid-Feb. Males occurred in very small numbers mostly in Mar. Larvae were sporadic during the season with a peak on 27 Feb. Twospotted spider mite (TSSM) motiles (immature stages + adults) and eggs, predatory mite motiles and eggs, sixspotted thrips, whitefly immatures, aphids, and parasitized aphids were monitored by collecting weekly leaf samples from 8 Nov. 2016 until 28 Mar. 2017. Predatory mites (Neoseiulus californicus) were released only on 18 Nov. because of low TSSM populations throughout the season. There were no differences in mean TSSM motiles per leaf among cover crop treatments or strawberry cultivars. More TSSM eggs were recorded from Sensation™ compared with Winterstar™ and 'Festival'. Fewer predatory mite motiles were found in 'Radiance' compared with the other 3 cultivars, but there was no difference in egg numbers. There were no difference in predatory mite motiles or eggs among cover crop treatments. Bi-weekly in situ counts detected seed bugs in high numbers and flea beetles in moderate numbers. A few big-eyed bugs, spiders, and ladybeetles were the main beneficial insects besides pollinators. Frankliniella bispinosa was the dominate species collected on flower samples and populations remained low until the last sampling date, with no difference among cultivars. Integrate Summer Leguminous Cover Crop into Nutrient Management Program for Organic Strawberry Production Systems A field trial that evaluated the cover crop (C. juncea), compost, and in-season fertigation was conducted in certified organic land at Citra, FL. Crotalaria juncea was planted at two seeding rates of 44.9 and 67.3 kg/ha in Jul. 2016 and terminated in Sep. along with a summer fallow control. Compost product was applied at C. juncea termination with no compost as the control. Containerized plants of Sensation™ strawberry were transplanted in Oct. Nitrogen (N) fertigation was applied at 0, 100%, and 150% of the standard rate and each plot received 78.5 kg/ha as a preplant application. A split-plot design with 4 replications was used, with C. juncea and compost treatment combinations in the whole plots and in-season fertigation rates in the subplots. Marketable and unmarketable fruit weights and numbers were determined from 28 Nov. 2016 to 3 May 2017. Plant growth assessment included above-ground dry weight, leaf area, and leaf number. Leaf tissue was analyzed for nutrient content. Fruit quality attributes such as soluble solids content, titratable acidity, dry matter content, firmness were assessed. Whole season marketable fruit yield per plant with 44.9 kg/ha C. juncea was higher than with the 67.3 kg/ha rate; however, neither of the C. juncea seeding rates differed significantly from the summer fallow control. A similar trend was observed in the sunn hemp treatments with regard to marketable fruit number and total fruit yield per plant. Compost had significant effect on fruit yields. The 100% and 150% fertigation treatments of produced higher yields than the without fertigation control, with no difference between the 100% and 150% treatments. While some significant effects of fertigation rates on plant growth compared with the no fertigation control were obtained, there was no impact of C. juncea or compost. Management of spotted wing drosophila and twospotted spider mite Studies addressing the management of SWD and TSSM focused on: SWD movement within the main on-station experiment utilizing Scentry traps. OMRI-approved products for managing SWD: (1) Azera (pyrethrins + neem), (2) Entrust (spinosad), (3) Grandevo (bacterial product), and (4) Veratran D (sabadilla alkaloids) in comparison with an untreated control. Site-specific treatments of the predatory mite, Neoseiulus californicus, for management of TSSM. OMRI-approved products for the management of TSSM: (1) Cosavet DF Micronized Sulfur, (2) Grandevo, (3) Aramite in comparison with a tap water control. Season Extension Potential of Low and High Tunnels in Organic Strawberry Production (North Carolina) Two 30'x96' high tunnels were used. Within each high tunnel, three low tunnels were installed. Four June-bearing strawberry cultivars were evaluated in one tunnel: Benicia, Camino Real, Florida Radiance and Winterstar™. The day-neutral strawberry cultivars: Albion and San Andreas were transplanted into the second high tunnel at two different dates (D1 and D2). A similar research design was used to evaluate low tunnels in an open-field production system. In the day-neutral cultivar trial, low tunnels significantly reduced the flower and fruit damage. Plants under low tunnels produced higher marketable and total yield than those without low tunnels. The D2 plants produced higher marketable and total yields than the D1 plants, despite that the biomass of D1 plants was higher than that of D2 plants from Oct. to Feb. 'San Andreas had higher marketable and total yields than 'Albion'. In the June-bearing strawberry trial, the cold damage to open blossoms, marketable yield, and total yield was not affected by low tunnels. There were significant effect of cultivar on yield. 'Florida Radiance' and Winterstar™ produced higher yields than 'Camino Real' and 'Benicia. Cold damage to open blooms in Jan. was not significantly different among cultivars.

Publications

  • Type: Conference Papers and Presentations Status: Published Year Published: 2017 Citation: Dosunmu, O., O.E. Liburd, and C. Chase. 2017. Efficacy of selected OMRI approved miticides on twospotted spider mite, Tetranychus urticae Koch on strawberry. Oral presentation. Florida Entomological Society Annual Meeting, San Juan, Puerto Rico.
  • Type: Conference Papers and Presentations Status: Published Year Published: 2017 Citation: Dosunmu, O. and O.E. Liburd. 2017. Management methods of twospotted spider mite, Tetranychus urticae Koch in field-grown strawberries. Southeastern Branch, Entomological Society of America, Memphis, Tennessee.
  • Type: Journal Articles Status: Published Year Published: 2017 Citation: Gu, S., W. Guan and J. E. Beck. 2017. Strawberry Cultivar Evaluation under High-tunnel and Organic Management in North Carolina. HortTechnology 27(1)78-83.
  • Type: Conference Papers and Presentations Status: Published Year Published: 2017 Citation: Gu, S., J. E. Beck and J. A. Moore. 2017. Characterizing High Tunnel Microclimate in Hardiness Zone 7 & 8 of North Carolina. Proceedings of the 7th National Small Farm Conference. pp 29-34. http://www.vsu.edu/nationalsmallfarmconference/Draft%20proceedings.pdf
  • Type: Conference Papers and Presentations Status: Published Year Published: 2017 Citation: Beck J. and Gu S. 2017. Soil Management Using Cover Crops in Organically Managed High Tunnels. Southern Cover Crops Conference Fact Sheet. http://www.southernsare.org/News-and-Media/SSARE-Bulletins/Cover-Crops-Research-Across-the-Southern-Region/Soil-Management-Using-Cover-Crops-in-Organically-Managed-High-Tunnels#
  • Type: Conference Papers and Presentations Status: Published Year Published: 2017 Citation: Gu, S. J. E. Beck and J. A. Moore. 2016. Including Low Tunnels in a High Tunnel for Winter Strawberry Production in Cold Hardiness Zone Seven. HortScience 51(9): S245 (abstract).
  • Type: Conference Papers and Presentations Status: Published Year Published: 2017 Citation: Chase, C.A. and S.B. Coplin. 2017. A cover crop mixture for weed and sting nematode management. Weed Science Society of America Meeting Abstract 320. http://wssaabstracts.com/public/45/proceedings.html.


Progress 09/01/15 to 08/31/16

Outputs
Target Audience:Target audiences included small scale strawberry growers, small farmers especially limited resource farmers who are interested in season extension of (organic) strawberries, extension agents, students, and other agricultural educators. Changes/Problems:Getting strawberry plugs for the 2015-2016 trials in North Carolina was a challenge because the research start date was two months earlier than the typical planting season in the region. We solved the problem by contacting nurseries in the mountains, which allowed us to purchase tips so we could raise our own plugs. Spider mites turned out to be a major problem in high tunnels, which forced us to stop the research in April. We plan to speed up the purchase process so predator mites can available for release in the tunnels at the appropriate time. What opportunities for training and professional development has the project provided?A new PhD student was recruited in summer 2016 to work on the organic strawberry nutrient management project. Two graduate students were hired to work on this project at NC A&T State University. Preliminary results and microclimate information were shared with extension agents at the Small Farm Week that took place in March, 2016 on NC A&T campus. How have the results been disseminated to communities of interest?Dr. Gu presented a 30-minute talk on High Tunnels for Expanding Organic Strawberry Seasons at the 2016 Southeast Region Fruit and Vegetable Expo that took place in Savannah, GA in January, 2016. He also delivered a poster presentation titled Including Low Tunnels in a High Tunnel for Winter Strawberry Production in Cold Hardiness Zone Seven at the 2016 ASHS conference in Atlanta GA. The low/high tunnel strawberry projects were shown at FOX 8 News covering the 2016 NC A&T Small Farm Week. What do you plan to do during the next reporting period to accomplish the goals?Research Objective 1: Assess the Efficacy of Off-season Cover Crops on Soil Health and in Suppressing Weeds, Sting Nematodes, Arthropod Pests, and Pathogens In late September, the main plots will be resampled to assess the effect of the cover crops on plant pathogenic nematode populations and the cover crops will be terminated after cover crop and weed growth assessment. After, cover crop residue incorporation and preplant fertilizer application, main plots will be divided into 4 raised beds equipped with drip irrigation tape and black plastic mulch. Subplot treatments to be applied to the 4 beds will consist of the strawberry cultivars: Strawberry Festival, Florida Radiance, Winterstar™, and FL-127. Tray transplants will be used to establish the crop in mid October. The trial will be monitored for persistence of weed suppression from the summer cover crops at monthly intervals during the strawberry crop. Soil will again be sampled at the end of the strawberry crop to assess plant pathogenic nematode populations. Soil will be sampled three times per year to assess soil health. Research Objective 2. Evaluate the Performance of Strawberry Cultivars in Open Field Organic Production Systems Half of the each subplot indicated in the previous paragraph will be used to compare growth and yield of the 4 strawberry cultivars. Research Objective 4: Integrate Summer Leguminous Cover Crop into Nutrient Management Program for Organic Strawberry Production Systems All data from the 2015-2016 studies will be analyzed and information will be disseminated through appropriate venues. The field trial on integrated nutrient management for organic strawberry production will be conducted during the 2016-2017 growing season. Research Objective 7: Assess the Season Extension Potential of Low and High Tunnels in Organic Strawberry Production In fall 2016, we will plant day-neutral cultivars (two cultivars, two planting dates) and June-bearing cultivars (four cultivars, one planting date) in two high tunnels, with relevant field trials conducted at the same time. Twelve low tunnels, one high tunnel, and 12 sets of data loggers have been purchased and will be (or have been) installed. A fall field day is scheduled for November 10, 2016 and strawberry is one of the crops to be demonstrated. A spring field day will take place in March 2017 during the annual Small Farm week. Research results will be disseminated at the 2017 Southeast Region Fruit and Vegetable Expo (invited and confirmed for two strawberry presentations), the annual S-ASHS conference (Mobile, AL), the biannual ARD conference (Atlanta, GA), and the 2017 ASHS conference (Big Island, Hawaii). Outreach objective 1: We will engage producer and county Extension faculty members in research and outreach planning, implementation and outcomes (1) We will initiate meetings of the Industry Liaison Panel (growers and industry representatives from a diverse group of formal and informal networks), which will provide overall guidance for this project. (2)We will submit the research assessment instrument for IRB approval. (3) We will conduct an assessment of the first season on-station research in Florida. Outreach objective 2: We will demonstrate the feasibility of organic strawberry production in low cost crop tunnels At the Florida A&M University (FAMU) Research and Extension Center, during the fall 2016, a PVC frame tunnel and a metal frame tunnel will be used to evaluate 'Festival', 'FL-127', 'Florida Radiance' and Winterstar™. Outreach objective 3: We will provide Extension faculty members, other local service providers, and growers with research results and recommendations (1)We will secure IFAS communications to videotape field day activities for our virtual field day. (2) We will secure IFAS communications to videotape mature strawberry plants to include in virtual research assessments. (3) We will secure IFAS communications to videotape important steps in the research process that have been only documented by photos so far (e.g., planting cover crops). (4) We will continue to take photos of other important steps in the research process including: bed formation, laying plastic, transplanting and periodic data collection between transplanting and harvest. (5) We will submit pre- and post-test instruments to be used at field days for IRB approval.

Impacts
What was accomplished under these goals? Research Objective 1: Assess the Efficacy of Off-season Cover Crops on Soil Health and in Suppressing Weeds, Sting Nematodes, Arthropod Pests, and Pathogens In summer 2016, the main on-station experiment was initiated in a certified organic field at the Plant Science Research and Education Unit in Citra, FL. The design for this experiment is a split plot with four main plot treatments arranged in a randomized complete block with 4 replications for a total of 16 main plots. Each main plot was surveyed to determine the population densities of existing vegetation and a composite soil sample was then collected from each main plot. Soil samples were divided into 3 subsamples and either sent to appropriate commercial laboratories to determine baseline soil health and soilborne nematode infestation or were placed in trays in the greenhouse to evaluate the baseline weed seed bank. The field was then tilled and the following 4 cover crop treatments were established: Sunn hemp (Crotalaria juncea; cv. Tropic Sun) monoculture Hairy indigo (Indigofera hirsuta) monoculture 4-way mixture ('AU Golden' sunn hemp; hairy indigo; slenderleaf rattlebox, C. ochroleuca, and American jointvetch, Aeshynomene americana) Weedy control Hairy indigo seed was acid-scarified prior to planting in order to break physical dormancy due to seed hardness. The cover crops were allowed to grow for a period of 8 weeks during which data were collected on leaf area index of the canopies, photosynthetically active radiation penetrating the canopies, cover crop plant height, cover crop density, and biomass. Weed density and biomass were also assessed. Research Objective 4: Integrate Summer Leguminous Cover Crop into Nutrient Management Program for Organic Strawberry Production Systems We conducted a preliminary study to assess the effect of a plant growth-promoting bacteria product on organic strawberry production during the 2015-2016 season in order to determine its potential for enhancing nutrient management in organic strawberry systems. Fruit yield and quality attributes were measured and data analyses are underway. A pilot greenhouse study was also initiated in summer 2016 to test different amino acid biostimulants for incorporation into an organic nutrient management program for strawberries. Sunn hemp as the summer leguminous cover crop was also planted in summer 2016 for establishing the field trial on organic strawberry nutrient management. Research Objective 7: Assess the Season Extension Potential of Low and High Tunnels in Organic Strawberry Production Two research trials (1) winter and spring production of day-neutral and June-bearing strawberries in high tunnels and in low tunnels within a high tunnel and (2) spring production of day-neutral and June-bearing strawberries in low tunnels have been conducted at NC A&T University Farm. Both projects used June-bearing cultivars Radiance and Winterstar™, and day-neutral cultivars Albion and San Andreas. Trial 1 was conducted in a 30 ft x 96 ft high tunnel. Six raised beds were made and three of them were assigned randomly for low tunnels, which were installed in late November 2015. The experiment was conducted as a completely randomized design. The treatment design was a split-plot design, with low tunnels/control (without low tunnels) as main plots and cultivars as subplots. There were 40 plants in each subplot. The trial was concluded on April 30, 2016. Results indicated that there was no significant difference between the low tunnel and control treatment in terms of the first harvest date, marketable yield, total yield and cold damage to open blossoms; however, the numerical values consistently favored the low tunnel treatment. For example, the total yield and marketable yield were 2.99 and 2.84 kg/plot in the low tunnel treatment, compared to 2.27 and 2.15 kg/plot in the control. Low tunnels also advanced the first harvest by five days. There were significant differences between cultivars for the date of first harvest and flower damage. 'Radiance' and 'San Andreas' were harvested 10 days earlier than 'Albion' and Winterstar™ and 'Radiance' had most severe flower damage (74.6%) while 'San Andreas' had the least (47.8%). Microclimate factors such as low air temperature, soil temperature and solar radiation were measured with Spectrum dataloggers and sensors every 30 minutes. Data did show some additional protection was provided by the low tunnels. Trial 2 was conducted in the open field with an experimental design similar to that of trial 1. Low tunnels were also installed in late November, removed (to avoid snow damage) in January and February, and re-installed in March. Trial 2 was concluded on May 30, 2016. There was no significant difference in terms of total yield between plots with low tunnels (2.2kg/plot) and without low tunnels (2.3kg/plot). Cultivars performed differently. Day-neutral cultivars had significantly lower yields than June-bearing cultivars. 'Albion' had the lowest yield (1.4 kg/plot), while Winterstar™ had the highest yield (2.8 kg/plot). Elevated temperatures that occurred in low tunnels did not seem to influence plant productivity. Statistical analyses on other variables (first harvest, canopy, fruit quality, cold damage and pest incidence) are not yet complete. Outreach objective 1: We will engage producer and county Extension faculty members in research and outreach planning, implementation and outcomes We also began the development oftwo separateinstruments that will be used for assessing research and field days, respectively. Outreach objective 2: We will demonstrate the feasibility of organic strawberry production in low cost crop tunnels At the Florida A&M University (FAMU) Research and Extension Center, sunn hemp was grown as a cover crop in summer 2016 on land that will be used in fall 2016 for assessment of organic strawberry production in low-cost crop tunnels. Outreach objective 3: We will provide Extension faculty members, other local service providers, and growers with research results and recommendations We established means for developing virtual assessments and virtual field days for growers and service providers. We securedassistance from IFAS Communications in order to accomplish the virtual components of our objectives. IFAS Communications will aid us in filming, website construction and web-based learning. We have also begun compiling other important materials pertaining to virtual assessments and field days. We took a considerable number of photos attwoimportant points in the research process: (1) planting cover cropsand (2) surveying the plots usingReal Time Kinematics (RTK) to ensure accuracy of plot locations across project years. The photos were subsequently captioned with detailed information to use during virtual assessments and field days. We beganwriting a literature review on web-based learning in anticipation of future publications.

Publications