Xanthomonas albilineans, X. campestris pv. campestris and X. sacchari

©Philippe Rott/UMR BGPI

Sugarcane leaf showing pencil line streaks caused by Xanthomonas albilineans

The Xanthomonas genus is composed of Gram-negative bacteria and comprises more than 27 species and 120 pathovars. They can infect the vascular system and/or the mesophyll of more than 120 monocotyledonous and 268 dicotyledonous plant species. Xanthomonas species cause major yield losses in numerous crops such as cotton, rice, tomato, cabbage, lemon trees, and sugarcane. Many of these Xanthomonas are also quarantine agents such as the sugarcane pathogen Xanthomonas albilineans (Xalb). Understanding the virulence of Xanthomonas pathogens is, therefore, of strategic importance.

©Damien Meyer/UMR CNRS-INRA 2594

[Meyer et al (2005) Mol. Plant Pathol. 6(3) : cover] Vascular propagation of a luciferase-tagged strain of Xanthomonas campestris pv. campestris (yellow colour) in an Arabidopsis leaf.

In this project, we want to focus our analyses on two vascular xanthomonas which overcome plant vascular immunity: Xalb which causes sugarcane leaf scald and Xanthomonas campestris pv. campestris (Xcc) which causes black rot of cabbage. Our goal is to identify by comparative genomics novel pathogenicity determinants that make these two species successful vascular pathogens.