Plant pathogenic bacteria are responsible for the loss of productivity of many crops in the world. Xanthomonas citri subsp. citri (Xcc) is responsible for citrus canker, a disease that causes great economic losses in citrus producing areas. Pseudomonas syringae pv. tomato DC3000 (Psto) produces bacterial speck on tomatoes. Ralstonia solanacearum (Rso) is a bacterial complex, responsible for multiple diseases in solanaceous plants. The sequencing of the genomes of these bacteria allowed the identification of blue and red-light photoreceptors. The study of these bacterial photoreceptors is proposed through the construction of deletion mutant and over-expression strains of these genes. Bacterial proteomes and protein glycosylation in Rso and Xcc will also be evaluated. Finally, endophytic bacteria will be used as a strategy for the control of these bacterial plant diseases.