Screening of Oryza species germplasm against a new variant of Xanthomonas oryzae pv. oryzae causing bacterial blight in Punjab

Development and deployment of resistant rice cultivars is the only prudent approach for the effective management of bacterial blight (BB) of rice caused by Xanthomonas oryzae pv. oryzae which occurs worldwide and is particularly endemic to most parts of Asia. Due to limited genetic variability in the cultivated rice germplasm, there is a need to broaden the rice gene pool by introgressing genes for BB resistance from diverse sources. A total of 45 accessions of Oryza glaberrima and 347 accessions of wild Oryza species including six A genome species were screened for reaction to a new variant of X. oryzae pv. oryzae over two years. Of these 20 accessions of Oryza glaberrima, 2 of Oryza rufipogon, four of Oryza nivara and three accessions of Oryza longistaminata were found to be resistant Studies on the inheritance and mapping of the genie regions responsible for resistance are in progress.