Effects of Rye Cover Crop Management on Seedcorn Maggot (Diptera: Anthomyiidae) Populations in Soybeans

Abstract

The effects of using a rye cover crop on seedcorn maggot, Delia platura (Meigen), populations in soybeans were studied for 2 years in Ohio. Populations of seedcorn maggots increased when the cover crop was turned into the soil, either by plowing and disking or by plowing alone. Spraying rye with paraquat before disking did not increase populations as much as when paraquat was not used. No increases were observed when the cover crop remained above ground, or when the rye was not present. Plant stand reductions usually resulted from seedcorn maggot population increases. Seedcorn maggot development within the field took ca. 408 thermal units (as measured by centigrade degree-days) from the time of disking to peak population emergence. Ramifications of using different cover crop management systems with regard to seedcorn maggots are discussed.