Observations on incidence of diseases were made from soybean fields in Assam during the year 2018. Seed rot (Pythium, Phytophthora), Seedling mortality (Phytophthora, Rhizoctonia, Pythium) and Root & lower stem decay (Fusarium, Rhizoctonia, Phytophthora) were common during rainy days viz. July 25th to until August 2nd week. Collar rot (Coll.R.) observed during August 15th Onward at seedling to Vegetative growth stage of the crop. Weather data revealed that in the month of July- August maximum rainfall was experienced resulting in severity of many diseases. Among foliar diseases Alternaria leaf spot appeared during first week of September vegetative growth stage of the crop .Wilt complex was observed August 25th Onward (high rainfall experienced) at vegetative growth stage of the crop. Similarly Rhizoctonia Aerial Blight (RAB) observed at vegetative growth stage of the crop during September 1st week onward. Cercospora leaf spot (CLS) and Pod Blight[ PB (Ct)] were noticed at flowering and pod formation stage viz. September 25th onward where intermittent rainfall was experienced by the crop. Soybean yellow mosaic virus (YMV) and Bacterial blight (BLB) observed during 15th September onward with intermittent rainfall at Vegetative and flowering stage of the crop.
