2012 Annual Report
1a.Objectives (from AD-416):
1. Evaluate four different cover crop systems for enhancement of beneficial insects and biotic resistance against pest thrips and the spread of TSWV in vegetable crop systems. The cropping systems will be: i) conventional black plastic mulch; ii) traditional cover crop, with spring cash crops transplanted into overwinter leguminous cover crops; iii) transitional cover crop, with the cash crops planted on black plastic overlaid in a cover system; iv) beneficial insect cover crop system.
2. Determine the effect of cover crop systems on soil fertility and vegetable crop vigor and yield.
3. Assess the economic value and practicality of cover cropping systems to growers through regional, collaborative on-farm research.
4. Foster adoption of effective practices by providing readily accessible information to growers, commodity groups and other stakeholders.
1b.Approach (from AD-416):
Objective 1 – The pest management impact of each of the four cover crop systems will be assessed with three cash crops (tomato, pepper and cucumber) in research station trials at Quincy, FL and Tifton, GA. Pest and beneficial insect communities will be evaluated by systematic sampling of cash crops, cover crops, and incidental weeds over time. TSWV incidence will be assessed in similar systematic sampling over time. The incidence of other major pests and diseases in cash crops will be monitored on a systematic basis.
Objective 2 – To assess the traditional cover crop benefits of the four systems, soil fertility and organic matter will be monitored over time in each of the cropping systems. Crop growth and plant nitrogen content will be monitored over time, and yields will be assessed at the end of each season. Weed growth within crop areas will be monitored over time by systematically recording weed species, their abundance and growth. To directly compare the economics of the different systems, data on production costs and crop returns, based on estimates from commercial sources, will be recorded for each cropping system.
Objective 3 – On-farm trials will be established at cooperator farms in Florida and Georgia. Similar data as recorded in the research station trials will be recorded in the on-farm trials. Economics of the different systems will be compared based on input costs and crop returns. The regional approach will facilitate guidance for future research to adapt systems to differing conditions and pest pressures.
Objective 4 – Field station and on-farm trials will provide sites where we will host demonstrations to compare different cropping systems to other growers. We will develop plans with cooperating growers for them to continue with successful cropping systems, which should help facilitate wider adoption of these programs. To further promote awareness to growers, information will be delivered at appropriate commodity group and other stakeholder meetings (e.g., NRCS, Florida Small Farms, Florida Organic Growers). In addition, information will be published in grower oriented magazines, (e.g., Southeast Farm Press, Georgia Fruit and Vegetable Grower News, Florida Grower). Information will be posted on the currently established websites of each institution (IPM Florida: ipm.ifas.ufl.edu, smallfarms.ifas.ufl.edu; University of Georgia: www.tswv.org; ARS: www.ars.usda.gov/saa/cmave/ibbru).
Research conducted in this subordinate project relates directly to Objective 1 of the parent project in developing habitat manipulation strategies as a part of improving management of thrips and tomato spotted wilt virus.
Tomato spotted wilt virus (TSWV), a viral disease transmitted by thrips, is the most important pest problem for vegetable producers in the southeastern USA and cannot be controlled with insecticides. Therefore, scientists with USDA-ARS CMAVE and cooperators at the University of Florida have initiated studies to determine if the use of certain companion plants can help reduce thrips and tomato spotted wilt in tomatoes, peppers and cucumbers, and to increase the sustainability of producing these crops. ARS scientists and cooperators from the University of Florida and the University of Georgia established the first year of a three year trial to evaluate four different cover crop systems for enhancement of beneficial insects and biotic resistance against pest thrips and the spread of TSWV in vegetable crop systems. The cropping systems are: i) conventional black plastic mulch; ii) traditional cover crop, with spring cash crops transplanted into overwinter leguminous cover crops; iii) transitional cover crop, with the cash crops planted on black plastic overlaid in a cover system; iv) beneficial insect cover crop system. The effects of cover crop systems on soil fertility and vegetable crop vigor and yield are being determined through systematic, periodic sampling.