Assessment of Prevalence and Severity of Sclerotinia Rot of Indian Mustard in Rajasthan and Haryana

Oilseed Brassica spp. is economically affected by Sclerotinia rot caused by Sclerotinia sclerotiorum worldwide. Field studies were conducted at farmers’ field to assess the prevalence and severity of Sclerotinia rot of Indian mustard (Brassica juncea) in 11 districts of Rajasthan and Haryana. Assessment indicates the significance and widespread occurrence of disease in Rajasthan and Haryana. Sclerotinia stem rot (SSR) incidence and severity were found more than 15 per cent and 3.2 grades, respectively in both states (average of 2009–10 and 2010–11 Rabi crop season). Maximum incidence was recorded at Dausa (29.2%) district in Rajasthan followed by Rohtak (24.8%) districts in Haryana and minimum 7.0 and 7.4 per cent at Jaipur and Bharatpur district, respectively. On the other hand SSR severity was also maximum (3.6 grades) in Dausa district and minimum (2.6 grades) in Bharatpur, Rajasthan. This clearly indicates that Sclerotinia rot disease has established its base in major mustard growing areas of Rajasthan and Haryana. Information gathered suggested that Sclerotinia rot is gaining importance in major mustard growing areas which may lead to disastrous crop failure as SSR incidence was recorded up to 50–60 per cent with maximum severity of grade of 4.0 at few locations. An efficient management programme could be formulated on the basis of assessment results of prevalence and severity of Sclerotinia rot on larger area approach.