Influence of Bacillus Subtilis cultures on the development of diseases of the leaf apparatus of sugar beet

The article presents the results of field studies aimed at studying the effect of suspensions of native Bacillus subtilis strains on the spread and intensity of development of the main diseases of the sugar beet leaf apparatus. The relevance of the study is due to the need to develop environmentally friendly plant protection methods, reduce the use of chemical fungicides and increase crop resistance to phytopathogens. The authors conducted field trials using Bacillus subtilis strains 20 and 17(8), which demonstrated high effectiveness in combating the main diseases of sugar beet: alternariasis, cercosporosis, fomosis, viral jaundice and powdery mildew. Treatment of plants with a suspension of Bacillus subtilis allowed to reduce the intensity of development and prevalence of these diseases compared with control samples and the standard biological preparation Alirin-B. In addition, the research results confirmed the positive effect of Bacillus subtilis treatment on sugar beet productivity. The yield of root crops in the treated variants increased by 5.2–10.7 t/ha compared to the control, which is associated with an improvement in the phytosanitary condition of crops. Despite the fact that the sugar content in root crops has changed slightly, the total sugar harvest per hectare increased by 1.26–1.82 t/ha due to increased yields. Thus, the conducted studies confirm the effectiveness of Bacillus subtilis strains 20 and 17(8) in the biological protection of sugar beet. Their use helps to reduce plant damage, increase yields and improve the environmental safety of agricultural technologies. The use of antagonistic microorganisms can become an important element of integrated plant protection systems, reducing the use of chemical fungicides and increasing the resistance of crops to phytopathogens.