Xanthomonas vesicatoria virulence factors involved in early stages of bacterial spot development in tomato

FELIPE V; ROMERO A; MONTECCHIA M; VOJNOV A; BIANCO MI; YARYURA P

PLANT PATHOLOGY

WILEY-BLACKWELL PUBLISHING, INC

Lugar: Londres; Año: 2018 p. 1936 - 1943

0032-0862

Xanthomonas vesicatoria (Xv)is a member of a species complex that causes bacterial spot on tomato, one ofthe most important diseases of this crop worldwide. Our objective was toanalyze several characteristics involved in Xvvirulence in relation to strain aggressiveness. We evaluated motility, biofilmformation, adhesion and production of xanthan in three local strains causingtomato bacterial spot in Argentina. The strains assayed presented differentialswarming and twitching motilities, adhesion and biofilm formation abilities.The most aggressive strain, BNM 208, exhibited the greatest swarming andtwitching motilities, and developed a mature biofilm with presence of definedcell clusters, a homogeneous and compact structure, and higher biomass andsubstratum coverage than the other two strains. Even though the three strainsproduced similar amounts of xanthan, BNM 208 produced the most viscousexopolysaccharide, which possibly relates to the better characteristics of itsbiofilm. Despite other differences, the three strains multiplied to similarlevels when they were infiltrated into the leaf. Our results suggest that theaggressiveness of Xv strains studiedin this work was related to their ability to move by flagella or type IV pili,adhere to leaves and form well developed biofilms, factors that improvephyllosphere colonization. A better understanding of the factors involved in Xv infection process at the early stageswould contribute to developing new control strategies for this phytopathogen.