Identification and Characterization of a Pseudomonas mosselii strain and its Antibacterial Function against Agrobacterium tumefaciens

Abstract

Agrobacterium tumefaciens is a gram negative bacterial that can infect a range of plants and result in root crown gall. A total number of 10328 bacterial strains were isolated from rhizosphere of cherry tree. One strain of LWB10 showed clear inhibition zone around the bacterial colony in YEB media inoculated with A. tumefaciens C58. Morphological, physiological, and biochemical characterization indicated that LWB10 belongs to member of the genus Pseudomonas. Results from the high-throughput matrix-assisted laser desorption/ionization biotypersmart system indicated that this strain had a score value of 2.247 relative to Pseudomonas mosselii. Also, phylogenetic analysis based on 16S rRNA gene sequence showed that strain LWB10 shared the highest similarity with Pseudomonas mosselii CIP 105259T. The antagonist strains also exhibit well in growth inhibition of other five A. tumefaciens strains. Coinoculation of LWB10 and plant pathogenic strain of A. tumefaciens CFCC1369 showed strongly inhibition of tumor formation in tomato stems. All the results demonstrated that the isolated strain is P. mosselii LWB10 and its antibacterial ability to A. tumefaciens may offer new way for management of crown gall disease in the future. Keywords: Agrobacterium tumefaciens, Pseudomonas mosselii, antagonist, biological control