Vol. 11, Issue 12 (2022)

Rice (Oryza sativa L.) is an important cereal crop covering 78 per cent of the cultivable area in Tripura. Among the biotic factors, rice blast caused by the hemibiotrophic fungus Magnaporthe grisea (T.T. Hebert) Barr is one of the most destructive diseases that affect the crop in all the rice growing ecosystem of Sepahijala district and causes significant crop losses. Initially disease symptoms appear as small elongated light white to gray-green spots with dark green borders. Under favourable condition, the small spot collapse together, becomes spindle shaped or elliptical spots and grayish-white centres with dark brownish margin. The phytopathogenic fungus attacks all the above plant parts including leaf, neck, collar, node, stem, panicle and sheath etc. Results revealed that seed treatment with Pseudomonas flourescens @ 10 g per kg of seed + foliar application of copper oxycholoride @ 2.5 g/L immediately after onset of disease recorded most effective treatment against blast disease both in leaf phase (21.09%) and neck phase (18.51%) with highest grain yield (4.89 t/ha), net return (Rs. 26,601/ha) and benefit cost ratio (1:1.43) as compared to untreated control. Integrated application of Pseudomonas flourescens and copper oxycholoride found to be effective for the management of blast in rice under organic eco-system.