Xanthomonas albilineans is an economically serious pathogen and a model system in the world of plant pathology. Other than the genes coding for the biosynthesis of the albicidin toxin, the genes involved in pathogenicity of X. albilineans are unknown. Furthermore, this pathogen is not known to possess avr and hrp genes like other bacteria causing plant diseases.The global aim of this project is to acquire knowledge of the genes involved in pathogenicity of this bacterial species. Thanks to various molecular methods and tools recently developed by Prof. Dean W. Gabriel at the University of Florida, USA, candidate pathogenicity genes will be identified by transposon mutagenesis, subtractive hybridization and gene hybridisation with specific probes.These genes will be cloned and sequenced, and their involvement in pathogenicity will be confirmed by complementation or site-directed mutagenesis and inoculation of sugarcane. My integration within Professor GabrielÂ's experienced team ensures the realization of this project, which adds new aspects to previous work with genes involved in plant-pathogen interactions.This study provides me the opportunity i/ to work on a highly interdisciplinary topic at an internationally renowned institution, ii/ to acquire new s kills and knowledge while broadening my international experience, iii/ to transfer the acquired knowledge to Europe, and iv/ to strengthen long-term collaboration with the USA.The knowledge and experience gained in this project will be valuable to the EU research community, including the European consortium on agricultural research in the tropics (Ecart), in order to better determine the underlying variability in pathogen weapons and plant responses, and to identify new control methods of plant diseases.It will therefore also contribute to food and energy security in the world because sugar produced from sugarcane is a major food supply and a major source for natural, clean and renewable energy.