Field experiments in Iowa and Ohio during 2011 and 2012 showed that two new pest management tactics – perimeter trap cropping and delayed removal of row covers – have encouraging potential for control of bacterial wilt on muskmelon with less reliance on insecticides in organic and conventional production. In conventional production, perimeter trap cropping (PTC) reduced the use of insecticides on a muskmelon main crop by an average of about 50% while incidence of bacterial wilt was lowered and yield was equivalent to non-PTC plots. The presence of a double row of ‘Buttercup’ winter squash as a perimeter trap crop successfully intercepted most cucumber beetles (the insects that spread bacterial wilt) before they entered the muskmelon crop. Although these squash perimeter rows required several insecticide sprays to protect against squash bug and squash vine borer, total insecticide use on treatment plots was still lower than on control plots. Under organic production, delaying row cover removal until 10 days after anthesis resulted in lower incidence of bacterial wilt than in control treatments (no row covers, and removal of row covers at anthesis) in all three site-years in which the disease appeared. Row covers also significantly suppressed a fungal disease, Alternaria leaf spot, in both years in OH. In general, use of row covers resulted in higher marketable yield than no row covers. However, the yield impact of the two delayed row cover removal treatments – opening the ends at anthesis, or leaving them closed – was variable compared to the row cover control (removal at anthesis). The project’s findings have been shared with cucurbit growers throughout the Midwest by presentations at state and regional grower meetings (Great Plains Fruit and Vegetable Growers Conference, PA Association for Sustainable Agriculture (PASA), Iowa Fruit and Vegetable Growers Conference, and Great Lakes Fruit and Vegetable Expo), two articles in the trade magazine American Vegetable Grower, and a webinar.
1. Assess ability of a) perimeter trap cropping, and b) extended-duration row covers, to suppress bacterial wilt and deliver acceptable yield in muskmelon. 2. Calculate costs and profits of applying perimeter trap cropping in conventional muskmelon production, and extended-duration row covers in organic production. 3. Communicate the findings to cucurbit growers throughout the North Central Region by means of on-farm demonstration trials, field days, webinars, a project website, trade journal articles, and regional meeting presentations. Performance targets for research, stated in the project proposal: • In 2 years of replicated field trials on muskmelon in Iowa and Ohio (2011 and 2012), determine the ability of perimeter trap cropping (PTC) to suppress bacterial wilt and reduce insecticide use under conventional production. • In 2 years of replicated field trials in Iowa and Ohio, determine the ability of delayed row cover removal (DRCR) to suppress bacterial wilt and reduce insecticide use under organic production practices. • Estimate costs and returns to each practice (PTC and DRCR) for North Central Region growers, using a partial budget analysis, based on results from the 2011-2012 field trials. Outreach targets: • Four on-farm demonstration trials per year, focusing on the DRCR tactic. • A field day in each state in both years, highlighting the project at an experimental trial site or at the farm of a cooperating grower. • Two 20-minute webinars, each highlighting one of the new practices (PTC and DRCR) used in the project. • Two articles on the project’s findings in regional or national trade journals (for example, American Vegetable Grower). • Presentations on project findings at regional grower meetings: the Great Plains Vegetable Growers Conference in St. Joseph, MO, the Great Lakes Fruit and Vegetable Expo, Grand Rapids, MI, and the Pennsylvania Society for Sustainable Agriculture (PASA).