STUDY OF THE INFLUENCE OF ENDOPHYTIC BACTERIA OF THE GENUS BACILLUS ON THE GROWTH AND STRESS RESISTANCE OF SPRING WHEAT AND SOYBEAN SEEDLS

Abstract

The studies were carried out to assess the indicators of seed germination, root length, level of lipid peroxidation, content of photosynthetic pigments and free proline in monocotyledonous and dicotyledonous crops when seeds were treated with strains of endophytic bacteria of the genus Bacillus. The scheme of vegetation experiments included modeling of 30% drought on sand and pre-sowing treatment of seeds of spring wheat variety Yoldyz and soybean variety Sultana with endophytic bacteria: Bacillus subtilis KS-55 AU, Bacillus cereus KS-56 AU, Bacillus pumilus KS-57 AU, Bacillus megaterium KS- 58 AU, Bacillus cereus KS-59 AU, Bacillus megaterium KS-60 AU and Bacillus pumilus KS-61 AU. Bacteria better stimulated root growth when using a titer of 1×106 cells in 1 ml of the drug (the increase was 0.6 cm on soybean with Bacillus subtilis KS-55 AU and Bacillus megaterium KS-60 AU and 0.4 cm on wheat with Bacillus cereus KS -56 AU, Bacillus cereus KS-59 AU and Bacillus pumilus KS-61 AU). In wheat, the Bacillus subtilis KS-55 AU strain stood out, treatment with which contributed to an increase in germination by 30%, a decrease in the level of lipid peroxidation by 46%, an increase in the amount of free proline by 148% and photosynthetic pigments by 6%, relative to the control variant. On soybean plants, the strain Bacillus subtilis KS-55 AU contributed to an increase in germination by 40%, Bacillus cereus KS-59 AU contributed to a decrease in the level of lipid peroxidation by 47% and the accumulation of proline by 73%, and Bacillus pumilus KS-61 AU increased the amount of total chlorophyll by 141%, relative to the control variant. Thus, we can conclude that the above strains of endophytic bacteria improve the growth and development of spring wheat and soybean seedlings, and also serve as inducers of crop resistance to soil drought.