Influence of microbiological fertilizer Baikal EM-1 on non-target objects of sunflower agrophytocenosis

The aim of the study is to evaluate the effectiveness of various methods of applying the microbiological fertilizer Baikal EM-1 in increasing the competitiveness of sunflower and the cellulose-decomposing capacity of the soil in the zone of sufficient moisture in the South of Russia. The studies were conducted in 2024-2025. Studies of the microbiological fertilizer Baikal EM-1 were carried out on crops of the early-ripening oilseed sunflower variety Belochka in the zone of sufficient moisture in the South of Russia. The most common pests are wireworms and false wireworms. There are sunflower longhorn beetle, sunflower thorn, various types of herbivorous bugs, and cotton bollworm. Of the diseases, the most common in the agroclimatic zone are alternaria, phomosis, ash rot, dry and white rot. The study was carried out against the background of a mixed type of weed infestation, when late spring weeds dominated (more than 40%). This is explained by the biology of sunflower. In addition, a specialized parasitic weed, sunflower broomrape, was found in the agrocenosis. Against the background of pre-sowing soil cultivation with a minimum number of weeds per 1 m2 (3 pcs/m2), the air-dry mass of the weed component decreases and is 148.65 g/m2, and with the maximum number of weeds per 1 m2 – 3886.08 g/m2, it has increased 26 times; against the background of pre-sowing seed treatment and the maximum number of weeds, their air-dry mass increased 25 times. The use of microbiological fertilizer in cultivation technology allows to reduce the underground air-dry mass of the root system by increasing the competitiveness of sunflower. The most intensive decomposition of cellulose occurs a month after the microbiological fertilizer gets into the soil. With pre-sowing soil treatment, the sunflower yield in the absence of weeds is 4.81 t/ha and 1.81 t/ha with the maximum number of weeds per 1 m2, which is 37.6%. The yield is slightly lower in the absence of weeds with pre-sowing seed treatment. It is advisable to use the obtained results to improve the technology of sunflower cultivation. When cultivating sunflower in the conditions of sufficient moisture in the South of Russia, in order to increase its competitiveness, it is advisable to carry out pre-sowing soil treatment with the microbiological fertilizer Baikal EM-1 at a concentration of 1.0%.