Biological protection of Salanum tuberosum L from pathogens using symbiotic bacteria Xenorhabdus bovienii entomopathogenic nematodes

Abstract

Abstract The results of field studies conducted in 2022-2022 are presented on the possible use of entopathogenic nematodes (family Steinernematidae) as a method of biological protection of potatoes by the symbiotic bacteria Xenorhabdus bovienii against pathogens of potato tubers (Streptomyces scabies Waks. et Henr., Rhizoctonia solani G. Kuhn) in the conditions of the European North of Russia. Immunological assessment of tubers after harvesting showed not only a decrease in the spread of Rhizoctonia solani and Streptomyces scabies by 52-64% and 14-52% compared to the control, but also their development to 33-83% and 14-52%, respectively. The most effective option was characterized by double treatment with an aqueous suspension of live cultures of symbiotic bacteria X. Bovienii (EPN-1), in which the degree of development of disease symptoms on tubers was reduced to 3% compared to the control (21%). When using EPN-1, the biological effectiveness against Streptomyces scabies was 27-39%, against Rhizoctonia solani - 29-31%. The greatest antifungal effect from the most dangerous pathogen in the region, R. Solani, was observed with single and double spraying of the leaf surface with a suspension of an autoclaved culture of symbiotic bacteria (EPN-2), a decrease in development by 31-41%, respectively. The yield of potato tubers depended on the method and frequency of treatments and amounted to 23.53-27.78 t/ha according to the experimental options. It was greatest with a single treatment of tubers with phytosporin and a double treatment of the leaf surface with EPN-2, higher than the control variant by 11–16 %, respectively.