An official website of the United States government.
The long-term goal of this project is to promote a systems approach to integrated pest management in cucurbits by developing and assessing strategies for and fostering farmer adoption of short cycle cover crops that suppress pests. <P>Our specific objectives in pursuit of this goal are: (1) optimize growth windows for mustard and buckwheat as short-cycle cover crops; (2) determine the effectiveness of pest suppression provided by short-cycle cover crops; (3) evaluate the impacts of short-cycle cover crops on pumpkin and cucumber growth and yield; (4) understand the relationship between allelochemical composition, concentration, and pest suppression, so that we can develop a biorational approach to IPM; and (5) conduct adaptation research and outreach to foster farmer adoption of the system.<P> Completing these objectives will address many current challenges in cucurbit pest management and develop sustainable tactics that farmers can readily adopt. This work will start the process of shifting pest management in cucurbits from an emphasis primarily on pesticide applications to an emphasis on integrative approaches that will protect the environment and human health. Conventional, sustainable, and organic farmers all can adopt the approaches we define in this project.
Non-Technical Summary: Pumpkins and cucumbers are key vegetable crops that are plagued by soil-borne weeds, insects, and diseases. Mustard and buckwheat, short cycle cover crops, could suppress these key pests. This project develops integrated pest management for sustainable pumpkin and pickle cropping systems and to ensure their adoption by farmers. <P> Approach: Our project will consist of two components: research station-based optimization research to characterize the benefits and limitations of short-cycle cover crops and adaptation research to be conducted at outlying research stations and on farms. We need to determine optimal planting times for our short-cycle cover crops in cucurbit cropping systems because planting time will determine what pest suppression is possible. In central Illinois, mustard growing windows are mid-March to mid-May (Scenario I: Early Spring) and late August to late October (Scenario IV: Early fall). Buckwheat growing windows are from early May to late June (Scenario II: Late Spring) and mid August to mid October (Scenario III: Late Summer). We predict that cover crop impact on pests and cucurbit yields will differ among growing windows. Weeds will be identified to species (broadleaf only) or grouped as grasses and counted between crop rows in 4 randomly placed quadrants/plots every 2 weeks. Severity of all diseases, particularly those caused by Phytophthora capsici and Fusarium spp., on leaves, vines, and fruit will be evaluated using a visual rating system based on percent area of each plant part affected by each plant disease. Soil samples will be collected at cucurbit planting and populations of the P. capsici determined by dilution plating. Arthropod population plots will be sampled using (1) pitfall traps operated weekly (less often for over-wintering cover crops) from the date the cover crops are planted until the pumpkin or cucumber crop is harvested; (2) soil samples collected monthly from the date the cover crop is planted until one month after the cucurbit crop is harvested; (3) yellow sticky traps to monitor flying insects from the date the cover crops are planted until the cucurbit crop is harvested; and (4) cover crop and crop examination (stand counts, percent defoliation, insects per plant, etc. as recommended for specific pests) and sweep net sampling from planting through plow-down or harvest. Pumpkin and pickle vegetative growth will be determined by measuring the width of 5 randomly selected plants every 2 weeks throughout the growing season. Pickling cucumbers will be once-over harvested when they reach the size standard for commercial production. Pumpkins will be harvested at full maturity. Both cucumber and pumpkin fruits will be graded according to USDA standards. Mustard samples collected from field studies (Objective 1) will be analyzed to identify the affect of mustard treatments on glucosinolate profiles and concentrations released into the soil. The frozen mustard residues will be incorporated into an 1:1 field soil: sand mixture in pots and emergence of pickles, cress, and ryegrass seedlings determined. An in vitro bioassay will determine activity of the mustards against Phytophthora capsici and Fusarium spp. Our adaptation efforts will include 3 components: (1) adaptation research/demonstrations at off-campus research facilities in IL, IN, and NY; (2) on-farm adaptation research/demonstrations; and (3) extension outreach programs.