Title: Effect of resistance inducing chemicals on Alternaria Blight disease of mustard (Brassica juncea L.)
Abstract: Alternaria blight disease of rapeseed mustard, caused by Alternaria brassicae (Berk.)Sacc.and Alternaria brassicicola (Schw) W iltshire, plays very important role for qualitative and quantitative yield loss of the crop.A study was conducted under field condition to identify some resistance inducing chemicals against the pathogen and can play a significant role in managing the Alternaria Blight disease.The resistance inducing chemicals which were tested at varying level of concentrations were salicylic acid, phosphoric acid, isonicotinic acid, benzoic acid, acebenzolarsmethyl and azooxytrobin 25% SC (as fungicidal check).Minimum disease severity of 31.49%and 29.47 % was recorded on leaves and siliqua respectively in case of isonicotinic acid 1000 ppm.The maximum inhibitory effects on spot development were recorded in case of isonicotinic acid 1000 ppm with minimum average number of spot (3.21) and average diameter of a single spot (3.70 mm).Maximum seed yield was recorded in case of isonicotinic acid 1000 ppm (1602 kg/ha) with an yield increase of 77.21 % over unsprayed control.