Increased resistance to Fusarium oxysporum f.sp. radicis-lycopersici in tomato plants treated with the endophytic bacterium Pseudomonas fluorescens strain 63-28.

摘要

The defence reactions of tomatoes inoculated with F. o. f.sp. radicis-lycopersici, with and without P. fluorescens strain 63-28 treatment, were investigated. The intensity of colonization by F. o. f.sp. radicis-lycopersici was lower in plants treated with P. fluorescens, with pathogen growth restricted to the outer root tissues and localization in the intercellular spaces. Disorganization of F. o. f.sp. radicis-lycopersici hyphae colonizing bacteria-treated roots was associated with chitin degradation. Therefore, it is suggested that plant chitinases were produced. Callose depositions were detected at the sites of attempted fungal penetration of the outer root cortex. It is suggested that P. fluorescens strain 63-28 may function as an inducer of resistance to F. o. f.sp. radicis-lycopersici in tomatoes.