Screening of rice genotypes for resistance to rice yellow mottle virus in Tanzania

Rice is the second major food crop in Tanzania contributing to food security and cash flow to poor resource farmers. However, Rice Yellow Mottle Virus (RYMV) is among the important disease devastating production in many rice growing regions in Tanzania. The reactions of 22 rice genotypes to an isolate of RYMV were studied. The appearance and development of symptoms in the various varieties were scored on a 1-9 scale. The observed reactions ranged from susceptible, moderately susceptible, moderately resistance, resistance to highly resistant. Nine per cent (9.09) of the varieties showed a high level of resistance while fifty per cent (50) were highly susceptible. The intermediate reactions were 27.27% resistant and 13.64% moderately resistant. This study was able to identify rice genotypes resistant to RYMV to be used in breeding program for introgression RYMV resistance into commercial released variety.