Influence of fertilization and pre-seeding inoculation systems on phosphate-mobilizing bacteria of sugar beets rhizosphere

Abstract

This article presents the results of research the influence of fertilizer systems and seeds inoculation on phosphate-mobilizing bacteria in sugar beet rhizosphere. For seeds bacterization was applied the Polymyxobacterin (contains spores and cells of Paenibacillus polymyxa, which can transform insoluble inorganic phosphates and organophosphates and to produce the phytohormonal substances) and mixture of the Polymyxobacterin with Trichoderma (Trichoderma). Microbiological analysis of rhizosphere soil of non-inoculated sugar beet plants was shown that the distribution of phosphate solubilizing microorganisms depends on the agricultural conditions. The using of both mineral and organo-mineral fertilizers stimulates the development of studied microorganisms. For increasing in rhizosphere of non-inoculated sugar beet plants a quantity of microorganisms that soluble mineral phosphates the use of mineral fertilizers (N160P120K160) with the addition of 32 t/ha manure is optimal. The application only mineral fertilizers to increase the number of microorganisms which capable to transform organic phosphorus compounds. In all trials including control without fertilizers, seed treatment by Polymyxobacterin increases the number of bacteria that soluble mineral phosphates. The most optimal conditions for the development of microorganisms that solubilize mineral and organic phosphorus compounds are the treatment of sugar beet seeds by mixture of Polymyxobacterin and Trichoderma and application of mineral fertilizers. Therefore, the obtained results indicate about significant impact of fertilizer types and seed treatment by microorganisms on the amount and composition of phosphate-mobilizing bacteria in the rhizosphere of sugar beet plants.