SYNERGISTIC EFFECT OF COMBINED USE OF ENDOPHYTIC BACTERIA AND HUMIC BIOSTIMULANTS ON SPRING BARLEY PRODUCTIVITY

The article presents research materials on assessing the effect of crop treatment with a biopreparation based on the endophytic bacterium Bacillus mojavensis PS-17 and its mixtures with various humic biostimulants on the productivity, disease resistance, and grain quality of spring barley. Field studies were carried out on the territory of the experimental fields of Agrobiotechnopark of Kazan State Agrarian University in 2023-2024. The scheme of the stationary field experiment provided for the study of the following options: control (without spraying); spraying plants with Humate +7 at a dose of 0.5 l / ha; spraying plants with Bigus extra at a dose of 0.5 l/ha; spraying plants by PS-17 at a dose of 1 l/ha; spraying plants with a tank mixture of the preparations Gumat +7 at a dose of 0.5 l/ha and PS-17 at a dose of 1 l/ha; spraying plants with a tank mixture of the preparations Bigus Extra at a dose of 0.5 l/ha and PS-17 at a dose of 1 l/ha. The initial humus content was 4%, mobile phosphorus - 275 mg/kg of soil according to Kirsanov and exchangeable potassium - 185 mg/kg of soil according to Kirsanov, pH - 6.1 in the salt extract. The experiment was repeated three times, the plots were placed using the randomized repetition method, the area of the experimental plots was 25 m². The system of primary and pre-sowing soil preparation included stubble cultivation, plowing, cultivation, pre-sowing harrowing, and the application of azophoska at a rate of 150 kg/ha. The least development of net leaf spot was observed when using a biopreparation based on the endophytic bacterium B.m. PS-17 (biological efficiency - 28.6%, compared to the control). Minimal development of root rot was noted when using a mixture of the humic preparation Humate +7 with the biopreparation based on B.m. PS-17 (biological efficiency - 13.8%, compared to the control). Biological efficiency was determined by the Abbott formula based on average values for 2 years. The use of all plant treatment options stimulated the growth of the leaf surface area of plants. The maximum indicators (17.3 m2/ha) were in the option - Humate + 7 + PS-17. Double application of the biopreparation Bigus Extra ensured the maximum yield increase of 13.88%, but its positive effect was due to a more significant increase in yield in the dry year of 2023. In 2024, the yield for all experimental options with treatments was approximately at the same level.