Author(s): AW Lenssen
Soybean production in Iowa USA is among the most productive for rainfed regions in the world. Despite generally having excellent soils, growing season temperatures and rainfall, soybean yields are decreased by weed interference and inadequate available soil water at key stages of crop development. A field study was conducted at two locations in Iowa in 2012 to determine if seed-applied fungicide or biofield treatments influenced weed community, soil volumetric water concentration and soybean yield and quality. Application of biofield treatment resulted in lower density of tall waterhemp density, greater soybean stand density at R8 stage and greater seed pod-1 compared to the absence of seed fungicide and biofield. Soil volumetric water content varied by seed fungicide x biofield x date interaction but differences were not consistent among treatment combinations. Overall, seed fungicide and biofield treatments had similar effects on soybean productivity, however additional research is necessary to determine if biofield treatment is a suitable replacement for seed fungicide application.