STRAIN PSEUDOMONAS FLUORESCENS DESIGNATED FOR CONTROL OF PHYTOPATHOGENIC FUNGI (VARIANTS), METHOD OF ITS ISOLATION AND USE, COMPOSITION CONTAINING THIS STRAIN AND METHOD OF ITS USE

摘要

agriculture, microbiology. SUBSTANCE: invention relates to agents used for control of plant sicknesses. New strains of bacterium Pseudomonas fluorescens NRRL B-21172 and NRRL B-21173 for control of phytopathogenic fungi are isolated. For isolation of indicated strains the library of transposone insertion mutants of the strain Pseudomonas is developed. Mutants are tested for capability to inhibit phytopathogenic fungus in vitro and mutants are selected on the basis of effectiveness of inhibition of phytopathogenic fungus, in part, fungus Rhizoctonia solani. On the base of strains the composition is developed for control of phytopathogenic fungi containing additionally a carrier with film-forming water-soluble noncross-linked polymer and cross-linked water-swelling polysaccharide. The parent concentration of microorganisms in the composition is 1 x 105 - 1 x 1011 CFU (colony-forming units) per 1 g. Starch, alginate, carrageenan, xanthane, sweet pod meal, methylcellulose or their mixture can be used as polymer. Obtained composition is used for treatment of plants or their parts, or seeds to protect their from phytopathogenic fungi, in part, fungi of species Rhizoctonia solani. Effectiveness of the composition is 60-90%. EFFECT: improved method of isolation, enhanced effectiveness of composition. 26 cl, 1 tbl, 10 ex