Rhizobacteria producing growth promoting substances as a bio-control agent against R. solani and F. solani causing root rot disease of tomato seedlings.

摘要

A total of 261 bacterial isolates was obtained from the rhizosphere of tomato, maize, clover, bean, cowpea, lupins, cucumber and banana in Egypt. The bacterial isolates were tested for their in vitro IAA and gibberellin production and antagonistic activity against Rhizoctonia solani and Fusarium solani. The isolates showing in vitro inhibition of the pathogens were collected and used as biological control agents in pot experiments with infected tomato plants. Isolates showing in vivo antagonistic properties against the pathogens were IAA and gibberellin sources, and also produced siderophores and hydrogen cyanide. The most efficient biological control agents included 3 isolates of Bacillus subtilis and one isolate of Pseudomonas synxantha..