Submitted to: American Phytopathological Society Annual Meeting
Publication Type: Abstract Only
Publication Acceptance Date: June 3, 2004
Publication Date: July 30, 2004
Citation: Singh, P., Wamishe, Y., Eizenga, G.C., Lee, F.N., Jia, Y. 2004. Development of molecular strategies to control rice sheath blight disease. American Phytopathological Society Annual Meeting. Phytopathology. 94(6):96. Technical Abstract: Sheath blight caused by Rhizoctonia solani is a serious disease of rice worldwide. No complete genetic source of resistance is known among rice cultivars. Rice cultivar Jasmine 85, shows considerable resistance to sheath blight and this resistance appears to be under polygenic control. The objective of this study was to characterize these minor resistance genes for developing molecular strategies to control sheath blight disease. First, sheath blight isolates were collected from Arkansas rice fields. These isolates were subsequently characterized based on anastomosis and sequences of the ribosomal DNA internal transcribed spacer. A detached leaf inoculation method was developed to assess lesions caused by the pathogen and discern differential cultivar responses. A subtractive cDNA library was constructed by the PCR-select cDNA subtraction method using mRNAs from Jasmine 85 sixteen hours after inoculation with a highly virulent isolate. Out of the 200 genes sequenced, 10%, 9%, 5% and 3% genes were predicted to have roles in defense, signal transduction, stress response and fungal-host association, respectively. The remaining included 24% regulatory, 21% unknown, 16% metabolism and 12% from fungal origin. Molecular interaction mechanisms of rice with R. solani will be discussed.