The potential of strip tillage and rowcovers for organic cucurbit production

Abstract

Plasticulture systems, the use of polyethylene mulch on raised beds with drip irrigation, are commonly used for the production of many cucurbit (Cucurbitaceae) crops. Although the use of plasticulture systems has many benefits, disadvantages include plastic disposal issues and costs and the intensive tillage required for installation. Strip tillage systems have been shown to decrease soil erosion, increase soil moisture retention, and increase soil microbial communities. Spunbonded polyethylene rowcover use has been shown to decrease early season striped cucumber beetle (Acalymma vittatum) and spotted cucumber beetle (Diabrotica undecimpunctata) populations and the incidence of bacterial wilt (Erwinia tracheiphila) while increasing yields. Plasticulture and strip tillage systems were compared with and without rowcovers at The Pennsylvania State University’s Russell E. Larson Research and Education Center in Rock Springs, PA. Two separate organically managed experiments were conducted, one being on ‘Lioness’ summer squash (SS; Cucurbita pepo), the other on ‘Athena’ muskmelon (MM; Cucumis melo). Both two-season experiments occurred during the 2013 and 2014 growing seasons. Yields, soil nitrate levels, soil and air temperatures, striped cucumber beetle populations, and incidence of bacterial wilt were measured. Plants grown in the strip tillage system generally had lower yields than in the plasticulture system in both years. Yield reductions observed in the strip tillage system in both years of the muskmelon experiment and in the first year of the summer squash experiment were beyond acceptable levels. The need for specialized tillage equipment, delayed planting, and high weed pressure were all obstacles to the successful use of strip tillage in these experiments. Rowcovers resulted in larger plants; however, yields were comparable to not using rowcovers within the strip tillage and plasticulture systems. There was low incidence of bacterial wilt in both years of the experiments despite observed striped cucumber beetle populations above the set threshold throughout all experiments.