The effectiveness of the use of entomopathogenic nematodes and their symbiotic bacteria in the potato protection system against diseases and pests in different agro-climatic zones of Russia

Laboratory and field studies conducted in 2023-2024. They were aimed at studying the pathogenicity of the entopathogenic nematodes (EPN) of the Steinernematidae family and their symbiotic bacteria Xenorhabdus nematophila and Xenorhabdus bovienii for pests (pounds) and causative agents of potato diseases (steamers, risoctonosis, and risoctonosis. phytoftorosis) in the conditions of the North-West and the Republic of Karelia. As a result of a comparative analysis of the antibiotic activity of symbiotic bacteria carried out on the basis of measuring the inhibition zones in vitro, it was revealed that all the studied strains of bacteria show activity against Rhizoctonia solani. The best results were demonstrated by the strain of X. nematophilus, which is the symbiont of the nematode of the type S. carpocapsae, its effectiveness was 45%.The immunological assessment of resistance to diseases after cleaning tubers showed that the biological drug Nemabakt and the symbiotic bacteria of nematodes X. bovienii most effectively protect tubers from the underlying diseases and wires during the vegetation. Against the souns ordinary, the best result was shown by Nemabakt when processing tubers before planting, completely suppressing the development of pathogen (100 %). The combination of Nemabakt with symbiones of nematodes S. feltiae protense reduced the affection of tubers by 59%. To combat rhizoctoniosis, Nemabakt and its combination with X. bovienii symbiontes were also effective, reducing the damage to tubers by 95-100 %. To protect against the wireworm, the most effective (at the level of chemical control) was the bacterial drug Nemabakt, its effectiveness was 59%. Analysis of productivity showed that the use of the studied drugs made it possible to increase potato yield by 20-46 %. The largest growth in the harvest of tubers was achieved when using S. feltiae protense Symbiones.