Survival of GacS/GacA mutants of the biological control bacterium Pseudomonas aureofaciens 30-84 in the wheat rhizosphere.

ABSTRACT: GacS/GacA comprises a two-component regulatory system that controls the expression of secondary metabolites required for the control of plant diseases in many pseudomonads. High mutation frequencies of gacS and gacA have been observed in liquid culture. We examined whether gacS/gacA mutants could competitively displace the wild-type populations on roots and thus pose a threat to the efficacy of biological control. The survival of a gac mutant alone and in competition with the wild type on roots was examined in the biological control strain Pseudomonas aureofaciens 30-84. In this bacterium, GacS/GacA controls the expression of phenazine antibiotics that are inhibitory to plant pathogenic fungi and enhance the competitive survival of the bacterium. Wheat seedlings were inoculated with strain

SUBMITTER: Chancey ST 

PROVIDER: S-EPMC126771 | biostudies-literature | 2002 Jul

REPOSITORIES: biostudies-literature