09-08-2013, 03:14 PM
Disease development and spread of sheath blight in different rice cultivars
ABSTRACT
Sheath blight caused by Rhizoctonia solani Kuhn, is a major disease of rice especially in highly intensive production system. To date, no rice varieties with complete resistant to the disease have been deployed in Asia. Mega rice varieties i.e. Pusa 44, PR108, PR116, PR118, PR120 along with susceptible check PAU 201 and tolerant check Jasmin 85 grown over large acreages were tested to their susceptibility to sheath blight. The field experiment was conducted in randomized block design with three replications at Punjab Agricultural University, Ludhiana, India. Sixteen plants in the centre were inoculated. The observations were made at 21 & 40 days after inoculation. The ability of the disease to spread differs among the mega rice varieties. Under lying spread mechanism of the disease from plant to plant over the course of an epidemic. Significant mega varieties effects were consistently found, indicating that mega varieties differ in their susceptibility to sheath blight. The most susceptible mega variety is PAU 201 and PR108 & PR116 were less susceptible.