Assessment of Genetic and Pathogenic Diversity of Xanthomonas oryzae pv. oryzae on High Yielding Local Variety, Tella Hamsa, from Farmer Fields in Gagillapur and Kompally, Andhra Pradesh

Rice is one of the most important food crops of the world which is grown in various agro climatic conditions and it encounters several biotic and abiotic stresses. Among biotic stresses bacterial leaf blight caused by Xanthomonas oryzae pv. oryzae is the major destructive disease in the world. There is no chemical effective against this disease, so growing resistant varieties is the only way to decrease the losses caused by the disease. To develop durable resistance varieties in the particular area under biotic stress conditions necessitates evaluation of rice genotypes. The present study revealed significant fingerprinting variations observed among the 44 Xanthomonas oryzae pv. oryzae isolates from Tella Hamsa genotype collected from different areas, Gagillapur and Kompally. In addition, much diverse pathotypic variation or virulence pattern was detected from set of differentials containing near isogenic lines and traditional cultivar differentials. Virulence data obtained from these differentials revealed that all of them were compatible with the resistance genes. However, these pathotypes were incompatible with the genes, xa-5, Xa-10, xa-13 and Xa-21 suggesting the possibility of deploying them for enhancing the resistance. Similar observations were reported in the research area of rice crop improvement. So, this study suggests the deployment of genes in combinations of two and three expressed wide spectrum of longevity resistance to bacterial blight pathogen