The bacterization effect of potato tubers by associative diazotrophs on the rhizospheric microflora

Field research was carried out in the potato department of the Omsk Agrarian Research Center. The purpose of research is to study the effect of biological products based on associative diazotrophs on the number of agronomically valuable microflora in the potato rhizosphere. It was established that the use of preplant bacterization of tubers had a predominantly stimulating effect on the state of the rhizosphere microbiocenosis. Average for 2022-2023 optimization of nitrogen nutrition of both plants and microorga-nisms (due to the fixation of atmospheric nitrogen by diazotrophs) increased almost equally the total number of microbial population under potato varieties Alena and Bylina Sibiri, by 19 (variant MF-1) and 26 % (strain PG-5 ) respectively in relation to the unfertilized control. The number of cellulose-degrading mic-roorganisms in the potato rhizosphere predominantly increased with the use of preplant bacterization of tubers, to a greater extent from treatment with Strain PG 5: by 19% in the Alena variety and by 39 % in the Bylina Sibiri variety; in other variants of the experiment, growth stimulation of the test group was also observed, but in to a lesser extent. Pre-planting inoculation of potato tubers most stimulated the growth of oligonitrophilic and phosphate-mobilizing microflora, as well as soil micromycetes; the increase relative to the control variant was 121 % in the Alena variety, 69 and 100 % when using strains MF-1 and 204, in the Bylina Sibiri variety 57 %, 40 and 82 %, respectively, when using strains PG-5 and 17-1.