Plant growth-promoting bacteria isolated from agrocenoses of agricultural plants

Abstract

The article presents data on the isolation of 7 forage and grain crops from agrocenoses (soy, barley,
alfalfa, rapeseed, safflower, donut and esparcet) of bacteria and the study of their PGPB properties.
PGPB properties were evaluated in isolated bacteria by studying the ability to dissolve phosphates,
nitrogen-fixing activity, antagonistic activity against the phytopathogen Fusarium graminearum, the ability to synthesize IUC. Determination of bacteria and actinobacteria before the genus was carried out by
studying morphological, physiological and biochemical properties.
Main results. It was found that 659 different bacterial isolates were isolated from agrocenoses of
various agricultural plants, while a significant part of the isolated isolates had a complex of properties
(up to 30% of the strains show a pronounced ability to produce IUC), which may provide biocontrol
and growth-stimulating effects. Among the isolated isolates, 191 are classified as gram-negative, 216 –
non-spore-forming gram-positive, 136 – actinobacteria, 117 – as gram-positive spore-forming bacteria
of the genus Bacillus. During the work, 7 promising strains were selected, representatives of the genera
Agromyces, Bacillus, Streptomyces, which have a complex of properties: growth-stimulating, phosphatedissolving, nitrogen-fixing and antagonistic activities for further development of highly effective microbiological preparations for crop production on their basis.
Key words: soil bacteria, agrocenosis, phosphate-solubilizing activity, nitrogen-fixing activity, antagonistic activity, synthesis of IUK.