Influence of biologicals on crop structure elements and spring barley yield

The aim of the study is to establish the optimal scheme for the use of biological preparations in the cul-tivation of spring barley. Objectives: to study the effect of pre-sowing seed treatment, growth stimulator, biological fertilizers, biofungicides and the combined use of biological products with a herbicide on the structural elements of spring barley crops; to determine the yield of spring barley under various plant pro-tection schemes. The studies were conducted in 2022–2024 at the Borsk Educational Scientific Production Center, located in the forest-steppe zone of the Krasnoyarsk Region. The studied barley variety is Krasnoyarsky 91. According to the State Register of Breeding Achievements, the variety is mid-late, the vegetation period is 75–93 days. The influence of the “year” factor on the yield of spring barley was the most significant and amounted to 60.1 %, the interaction of the “cultivation technology × year” factors was 32.4 %, and the “cultivation technology” factor was 6.7 %. The use of complex biological protection in the tillering-tube emergence phase led to an increase in the length, grain content and weight of the ear, the number of productive stems and the weight of 1000 barley grains. The yield of barley exceeded the control when using pre-sowing seed treatment with biopreparations according to the maximum program, as well as when treating with biopreparations in the tillering phase - tube emergence in the second, fourth and fifth options. The yield was 5.2 t/ha when using pre-sowing seed treatment and Biodux during vegetation; when adding biofertilizers, biofungicides to the above treatments – 6.7 t/ha; when using a growth stimulator, biofertilizers, biofungicides and a herbicide – 6.1 t/ha.