Rhizosphere bacteria can positively influence plant growth by direct and indirect mechanisms. A total of 112 bacterial strains were isolated from the
rhizosphere of rice and tested for plant beneficial activities such as siderophore production, cell-wall-degrading enzyme production, hydrogen cyanide
(HCN) production and antifungal activity against rice blast disease fungus. The actinomycetes count was 3.8 x 10(6) CFU/g soil. Streptomyces strains PC 12, D
4.1, D 4.3 and W1 showed strong growth inhibition of blast disease fungus, Pyricularia sp. (87.3%, 82.2%, 80.0% and 80.5%) in vitro. Greenhouse experiments
revealed that rice plants treated with Streptomyces strain PC 12 recorded maximum plant height, root length and root dry weight compared to the control.
Taxonomic characterization of this strain on the basis of 16S rRNA gene sequence led to its identification as Streptomyces palmae PC 12. Streptomyces
palmae PC 12 may be