Isolation and Characterization of Amycolatopsis sp. strain CRJ2-11 with Biocontrol and Plant Growth Promoting Potential from Upland Rice Rhizosphere in Manipur, India

Fifty seven actinomycetes isolated from upland rice rhizosphere in Chandel, Manipur were subjected to antifungal assays by Dual Culture technique. Five strains showed biocontrol potential against five major rice fungal pathogens viz. Rhizoctonia oryzae-sativae, Fusarium oxysporum, Bipolaris oryzae, Curvularia oryzae and Pyricularia oryzae. Of the five biocontrol strains listed here, one (CRJ2-11) showed highest antagonistic potential. The bioactive strain was also positive for various plant growth promoting traits such as indole-3-acetic acid (IAA) and siderophore production and phosphate solubilization. The strain produced significant levels of IAA (196 μg/ml) and solubilized substantial amounts of inorganic phosphate (82.49 μg/ml) respectively. Characterization of the strain CRJ2-11 by phenotypic tests and 16s rDNA sequence analysis indicated it to be a species of Amycolatopsis having closest affinity with Amycolatopsis keratiniphila (99%). Hence, the potential biocontrol and PGP (plant growth-promoting) strain CRJ2-11 was designated as Amycolatopsis sp. strain CRJ2-11.