Effects of agronomic practices on the timeline of Heterodera glycines establishment in a new location

Abstract

How soybean cyst nematode (SCN,Heterodera glycines) adapts when introduced into a new location under tillage, rotation and crop treatments is unknown. SCN race 3 (Hg Type 0) was introduced into a sandy loam field at more than 4000 eggs (100 cm3soil)−1and observed over 6 years under till and no-till, and either maize (Zea mays; C), SCN race 3 resistant soybean (Glycine max; R) or susceptible soybean (S) monocrop, or RCRC and SCSC rotations. While SCN population density was lower in no-till than in tilled treatments, and highest in S and lowest in C or RC rotations, it was detected at less than 1 cyst (100 cm3soil)−1. This suggests a prolonged phase of decline from the introduced levels. The interaction effects of tillage, rotation and/or time on SCN suggest that outcomes vary by agronomic practice and time, providing agro-biologically-based understanding of SCN establishment in a new location.