GENETIC DIVERSITY WITHIN THE POPULATION OF XANTHOMONAS-ORYZAE PV ORYZAE IN INDIA

Xanthomonas oryzae pathovar oryzae causes a serious disease of rice in India and is endemic in all of the major rice-growing areas of the co untry. Sixty-seven X. oryzae pv. oryzae strains, collected mostly in 1 994 and 1995, from 18 locations in India were analyzed by DNA fingerpr inting methods using two separate repeat element probes from the X. or yzae pv. oryzae genome. These results show that strains belonging to a single pathogen lineage can be isolated from 16 of the 18 locations s ampled; many of these locations are separated from each other by hundr eds of kilometers and represent ecologically diverse rice-growing area s. Pathotyping analysis indicated that the strains in this lineage bel ong to pathotype 1b of X. oryzae pv. oryzae.