Ali Raza

Bacterial leaf blight of rice:- Causal organisms:- Xanthomonas oryzae p.v oryzae Symptoms:- Leaf blight is very much common which is characterized by linear yellow to straw color size of stripes with wavy margins. Usually symptom start on the tips and progressive downward. Followed by drying and twisting of leaf tips and rapid extension of margins . Blight leaf cross wise cover the large area of leaf in some case the strips may appear anywhere on leaf lamina. The blight extend leaf strikes comes and killer in dry weather opaque and turgid drop of bacterial oozes which dry into yellowish weeds can be seen of a leaf surface . These drop are washed down by rain. The usually 4-6 weeks after transplantation. Disease cycle:- The bacteria survive off season in seed wheat host rice Volantis plant and infected rice straw and stubbles The infected seed or major primary seed of inoculum and secondary spread is usually through wound and stomata by bacterial cell disseminated by winds born ran drop splashes by irrigation water as rain water coming from infected field or at by contact with disease and healthy leaf Management Streptomycin and chloramphenicol are effective and seed born inoculum can minimize by soaking 12hours in 0.25 % agrimycin 15% streptomycin. 0.05 % w.t season and transferring the seed to hot water 50-54⁰C for 30 minutes. Smple soaking in ordinary water and diping in hot water 50-54⁰C. He spry of antibiotics that is agromycin is also recommended use of resistant varieties. The extract of neem and turmeric and also effective to control this disease. The extract of garlic and citrus lemon also suppress the bacterial leaf blight of rice.