Bakanae disease caused by Fusarium fujikuroi is animportant diseases on rice. Pseudomonas fluorescens
produces the broad-spectrum antibiotic phenazine-carboxylic
acid (PCA), which is active against a variety of fungal root
pathogens. In this study two genes from seven gene locus of
phenazine were cloned in Escherichia coli DH5α.
The contaminated rice samples were collected from infected
farms of Guilan. 238 bacteria were isolated from the
rhizosphere. The antagonistic ability of 12 of which, was
demonstrated with dual culture method. From the biochemical
and culture results, 8 isolated were identified as P.
fluorescens. The two genes from seven gene locus of
phenazine were cloned into E. coli DH5α.
We speculate that P. fluorescens that produce
2,4-diacetylphloroglucinol (Phl) play an important role in
the natural suppressiveness of this soil to causal agent of
collar and root rot of rice.