Skip to main content
ARS Home » Research » Publications at this Location » Publication #99176
Title: THE TOTAL CATABOLIC CAPABILITIES OF ENTEROBACTER CLOACAE ARE NOT REQUIRED FOR SUPPRESSION OF DAMPING-OFF OF CUCUMBER CAUSED BY PYTHIUM ULTIMUM

Author
item Roberts, Daniel
item Dery, Pierre

Submitted to: Phytopathology
Publication Type: Abstract Only
Publication Acceptance Date: 3/10/1999
Publication Date: N/A
Citation: N/A

Interpretive Summary: N/A.

Technical Abstract: Cucumber seeds release a complex mixture of reduced carbon compounds during germination. Nine mutants of Enterobacter cloacae strain 501R3 were used to determine if the total catabolic capabilities of this bacterium were required for suppression of damping-off caused by Pythium ultimum. Strain A-11 contains a transposon within the pfkA gene and is affected in general carbohydrate catabolism. Transposon mutants M2, M5, M59, M64, M83, 501R3orn, M2orn, and M59orn are decreased in utilization of amino acids or or amino acids and peptides. For biocontrol assays, seeds were treated with individual bacterial strains and sown in potting mix infested with sporangia of P. ultimum. Strain M2orn was the only strain with a plant stand significantly lower (P < 0.05) than strain 501R3 at eight days after planting. All treatments containing mutants or strain 501R3 resulted in a plant stand significantly greater than the pathogen check. These data demonstrate that the total catabolic capabilities of E. cloacae are not required for suppression of damping-off of cucumber caused by P. ultimum.