Impact of microbial preparations on the activity of rhizosphere and the productivity of oil flax under no-till

Abstract

Microbial preparations improve mineral nutrition of plants, protect against phytopathogens, and increase their resistance to stress factors. The aim of our research is to study the effect of microbial preparations on the biological activity of rhizosphere and the productivity of oil flax under no-till in the Crimean Steppe. Microbiological analysis of the rhizosphere of oil flax showed that there is a tendency to increase the number of microorganisms of various ecological and trophic groups both under the conditions of the conventional farming system (CFS) and no-till when seeds are inoculated with a complex of microbial preparations (CMP). Under CFS, the number of microorganisms using mineral forms of nitrogen as nutrition increased by 28 %; pedotrophs – by 37 %; ammonifiers and oligotrophs increased under both farming systems. The total number of nitrogen fixers increased by 29 % under CFS as a result of biological preparations use, while under no-till there was only a trend towards increasing the amount of azotobacter. The number of actinomycetes increased under the influence of CMP by 50% under direct sowing; micromycetes decreased under both farming systems. The number of cellulose-degrading microorganisms increased by 18 and 27 % under no- till and CFS, respectively. The yield of oilseed flax under no-till was 0.11 t/ha (12.9 %) higher than under conventional farming system. On average, over three years (2017-2019), an increase in yield amounted to 0.12 t/ha (19%) due to the use of microbial preparations.