The genomics of xanthomonas oryzae

Abstract

Xanthomonas oryzae pathovars oryzae and oryzicola cause bacterial leaf blight and bacterial leaf streak of rice, respectively, two diseases that pose a significant threat to global rice yields. The first four complete genome sequences of X. oryzae strains yielded a wealth of information about virulence factor content, mobile genetic elements, and taxonomic differences among strains of X. oryzae pathovars oryzae and oryzicola. The genomes have been applied in systematic studies of gene function and expression and in comparative analyses of the differences between pathovars. X. oryzae genome sequences facilitated the current understanding of the evolutionary history and diversity of type III secreted effectors, including transcriptional activator-like (TAL) effectors, and contributed to the discovery of the code-mediating TAL effector recognition specificity. The genomes have also been instrumental in the development of improved tools for epidemiological typing and disease diagnostics. This chapter focuses on the contributions of genomic sequencing projects to the understanding of X. oryzae biology and diversity and the future questions that genomics will help address.