Technology of Using Biological Preparations Based on Entomopathogenic Nematodes and Symbiotic Bacteria to Protect Potatoes From Pests and Diseases in the North-West of Russia

In the period 2024-2025, research was conducted to develop a technology using biological products based on entomopathogenic nematodes of the Steinemematidae family and their symbiotic bacteria, Xenorhabdus nematophila and Xenorhabdus bovienii. The evaluation was conducted through field trials, followed by an analysis of their effectiveness as a means of protecting potatoes from abiotic and biotic stressors. The main goal of the study was to develop a technology for the multifunctional use of nematode-bacterial complexes for the biological protection of potatoes from pests and pathogens. The results of the immunological assessment of tubers after harvesting showed that the most effective method for effectively controlling the main diseases and damage to tubers caused by wireworms during the growing season is the combined use of the biological product Nemabat, and symbiotic bacteria X. bovienii. The developed technology involves spraying the soil and tubers with a suspension of invasive nematode larvae and an aqueous suspension of bacteria. In conditions of elevated ambient temperatures, foliar treatment with an aqueous suspension of symbiotic bacteria X. nematophilus demonstrated high effectiveness in protecting potatoes from pathogens, providing protection against rhizoctonia (38-100%), late blight (12-100%), and common scab (50-100%). The innovative technology based on the multifunctional use of nematode-bacterial complexes has proven to be effective in protecting potatoes. The maximum yield of tubers was achieved by combining the use of Nemabact and the symbionts X. bovienii and S. feltiae protense, resulting in an increase of 1,9 t/ha (7%) in yield due to an increase in the number and weight of tubers. The developed technology, based on the multifunctional use of nematode-bacterial complexes, allows for more effective protection of potatoes from harmful organisms.