Screening/rescreening of rice entries for sheath blight resistant under field condition

Abstract

Rice (Oryza sativa L.) is second most important cereal and the staple food for more than half of the world’s population. Sheath blight of rice caused by Rhizoctonia solani. The disease has been named as “sheath blight” because of primary infection on leaf sheath. The yield loss due to this disease is reported to range from 5.2-50 per cent depending on the environmental conditions, crop stages at which the disease occurs, cultivation practices and cultivars used. Significant grain yield losses were reported due to sheath blight when susceptible varieties were grown. Thirty one entries / cultivars of rice were screened under natural field condition for resistance of for resistance of sheath blight of rice. The 31 different rice entries and cultivars were screened for sheath blight resistant purpose. The thirty one entries were screened against sheath blight of rice under artificial inoculation no entry was recorded for highly resistance reaction. Twenty one entries designated as 22250, 21665, 3305, 545191, 545206, 450294, 463893, 22164, CRHR-32, NDR-359, 23135, 23144, 23174, 23089, 23101, 23114, 22017, 23115, 23652, 23834 were showed resistant reaction (Score-3). While the nine entries designated as R1896-81-2-59-1, R2048- 187-2-128-1, ARR-8, FSVT-MS-18, FSVT-MS-20, 213, 1714, 2717 and the variety IR10F36 showed moderately resistant reaction (Score-5). Rest of the one entry 212 was recorded as susceptible (Score-7) in their reactions against the disease.