Xanthomonas oryzae is a species of proteobacteria. The major host of the bacteria is rice .
The species contains two pathovars which are non-European: Xanthomonas oryzae pv. oryzae and Xanthomonas oryzae pv. oryzicola .
Host resistance gene, Xa21,from Oryza longistaminata is integrated into the genome of Oryza sativa for the board range resistance of rice blight disease caused by Xanthomonas oryzae pv. oryzae