THE INFLUENCE OF THE USE OF BIOPREPARATIONS BASED ON VARIOUS ENDOPHYTIC BACTERIA OF THE GENUS BACILLUS ON PHYTOPATHOGENIC MICROMYCETES AND PRODUCTIVITY OF SPRING WHEAT

The studies were conducted to assess the effect of using two biological biopreparations based on endophytic bacteria on phytopathogenic fungi and the productivity of spring wheat of the Ulyanovskaya 105 variety. The studies were carried out in years with both favorable (2020, 2022) and extremely dry (2021) moisture conditions during the growing season. Field experiments were laid on highly fertile gray forest soil in the Predkama zone of the Republic of Tatarstan. Bacillus monojavensis PS17 (endophytic seed bacterium) and Bacillus amyloliquefaciens RECB-95 (endophytic root and stem bacterium) bacteria were used as biological agents. Biopreparations based on these bacteria were used for seed treatment (rate of 1 l/t) and for spraying plants in the heading phase (1.0 l/ha). The control variant was without any treatments, and the standard was the scheme using chemical fungicides (seed treatment with Lamador (0.2 l/t), spraying with PropiShans (0.5 l/ha)). In laboratory conditions, high fungicidal activity of Bacillus mojavensis PS17 and Bacillus amyloliquefaciens RECB-95 against Fusarium fungi was found. An advantage of using Bacillus amyloligurosine RECB-95 when treating spring wheat seeds in suppressing Fusarium infection in the soil of the root zone of plants was found. Both strains, when treated with seeds, suppressed the development of Cochliobolus sativus in the soil of the root zone of wheat plants. The most effective control of root rot at the early stages of spring wheat plant development was ensured by using the scheme with seed treatment with Bacillus mojavensis PS17. The use of biopreparations based on endophytic bacteria reduced the development of leaf mycoses of spring wheat, and no significant differences were noted between strains in terms of disease control efficiency. The strongest positive effect on the yield of spring wheat was exerted by the use of biopreparations based on endophytic bacteria under conditions of an extremely dry vegetation period. The maximum yield of spring wheat was ensured by the biological protection scheme with the endophytic bacterium of wheat seeds Bacillus mojavensis PS17.