Developing a comprehensive management program for sudden death syndrome of soybean

摘要

Sudden death syndrome (SDS) of soybean, caused by Fusarium viguliforme (=Fusarium solani f. sp. gfycines), has become a prominent disease in many soybean production states in the U.S. Infection by the pathogen begins in the seedling stage and continues throughout the growing season. The infection and colonization damages the root system; however it is the foliar phase of the disease that results in severe yield loss. The initial foliar symptoms are intermittent chlorotic spots that begin at or near flowering. As the severity increases, the spots coalesce to form elongated, interveinal areas that become necrotic. In severe cases, defoliation and pod loss occur leaving only a bare stem with upright petioles. (Roy et al. 1997). Epidemics of SDS are greatest when soil moisture is high and soil temperatures are low during the early reproductive stages of the plant. The greatest impact of SDS is in north central states with annual yield losses exceeding 2 x 10~6 metric tons (Wrather & Koenning, 2006).