Influence of Winter Annual Weed Management and Crop Rotation on Soybean Cyst Nematode (Heterodera Glycines) and Winter Annual Weeds

Abstract Certain winter annual weeds have been documented as alternative hosts to soybean cyst nematode (SCN), and infestations of such species have become common in no-till production fields in the Midwest. This research was conducted to determine the influence of herbicide- and cover-crop-based winter annual weed management systems and crop rotation on winter annual weed growth and seed production, SCN population density, and crop yield. Two crop rotations (continuous soybean and soybean-corn) and six winter annual weed management systems (a nontreated control, fall and spring herbicide applications, spring-applied herbicide, fall-applied herbicide, fall-seeded annual ryegrass, and fall-seeded winter wheat) were evaluated in no-tillage systems from fall 2003 to 2006 at West Lafayette, IN and Vincennes, IN. Fall or spring herbicide treatments generally resulted in lower winter annual weed densities than cover crops. Densities of henbit and purple deadnettle increased over years in the cover crop systems ...