INFLUENCE OF BACILLUS-INTERMEDIUS RNASE ON PRODUCTION OF SECONDARY METABOLITES BY RHIZOBIUM-MELILOTI

Production of biologically active compounds by Rhizobium meliloti was studied in culture growth dynamics. This root-nodule bacterium was sho wn to synthesize growth factors only in the phase of decelerated growt h and the stationary phase. Addition of RNase in the phase of decelera ted growth enhanced the ability of rhizobia to stimulate plant growth, which was manifested as an increase in the germination energy and ger minating capacity of alfalfa seeds and the biomass accumulation by see dlings. Microbial RNase was found to stimulate the production of phyto hormones, indolylacetic acid in particular. RNase treatment was also s hown to increase the antagonistic activity of root-nodule bacteria aga inst Alternaria and Fusarium.