CHARACTERIZATION OF RICE YELLOW MOTTLE VIRUS ISOLATES IN SUDANO-SAHELIAN AREAS

The use of a panel of polyclonal antisera and monoclonal antibodies (M Abs) raised against West African isolates of rice yellow mottle virus (RYMV) in ELISA resulted in separation of 73 RYMV isolates into three distinct serogroups. Using a set of differential rice varieties, the s erogroups could be correlated to two RYMV pathotypes. A relationship w as found between serological properties of the RYMV isolates and their probable ecological origin. It was concluded that RYMV isolates origi nating in closely related agroecological zones displayed variability i n coat protein and pathogenicity. This should be taken into account in developing tolerant or resistant rice varieties.