Studies on Rice Tungro Disease : Gene Expression Analysis of Rice Genotypes during Rice Tungro Virus Infection

Rice tungro disease (RTD) is a major constraint in production of rice (Oryza sativa L.) not only in India but in all South and Southeast Asia. Host plant resistance is the most effective and economical method for control of this virus disease. Regular research is required in search of useful genes providing resistance against various strains of virus. This has necessitated a detailed study on gene expression analysis of rice genotypes infected with rice tungro virus. One hundred and twenty rice genotypes (120) comprising of fifty one (51) rice entries of International Rice Tungro Nursery (IRTN) lines and sixty six (66) rice entries of N 22 mutants along with two resistant rice cultivar and one susceptible check were screened against RTD using viruliferous GLH vector under glasshouse conditions. Six rice cultivars T(N)1 and Tapaswini (susceptible), IR 20 and IR 67406-6-3-2-3 (moderately resistant), TKM-6 and Vikramarya (resistant) were tested against RTD on yield parameters. Further, Gene expression studies were carried out with selected genes (PBZ1, LRR, CAT and RF2a) in susceptible rice cv. T(N)1 and resistant rice cv. Nidhi by artificial inoculation of RTV using viruliferous GLH.