Vegetables and oil seeds Brassica are most important crops worldwide where the crops suffer different diseases. Alternaria spot/blight is severe seed-borne fungal disease. By the disease more than 90% of various Brassica seeds are infected by the disease where upto 30% yield loss has been reported specially in oil seed brassica in Bangladesh and 35-40% in India. Existing of various sources of inoculum and wide range in spore dispersal with uncertainty of the level of disease, the disease is very difficult to manage although several protective fungicides are effective in controlling the...