Biological Characteristics of Streptomyces sp. VIZR-018 Strain and Its Effect on Potato Disease Incidence and Yield in the Stavropol Region

This study presents data on the biological activity of strain Streptomyces sp. VIZR-018, isolated from Crimean soil, against plant pathogens and phytophagous insects under laboratory and field conditions in the Stavropol region. The strain exhibited high antagonistic activity against a broad spectrum of phytopathogenic fungi and bacteria, insecticidal activity against a group of sucking arthropods, and phytoregulatory activity towards potato, cucumber, wheat, and barley plants. In field trials, pre-planting tuber treatment followed by two applications of a liquid formulation during the potato growing season had a stimulating effect on plant height (+64–71%), stem count (+30–33%), and the onset of flowering. The biological efficacy of the preparation against late blight development, compared to the farm’s standard protection system, ranged from 44.7 to 65.3%. As a result of treatment with the liquid Streptomyces sp. VIZR-018 sample, potato yield increased by 0.8–6.3 t/ha, equivalent to 9–68% compared to the control. In the laboratory, the strain demonstrated high insecticidal activity against the vetch aphid (Megoura viciae), with 100% mortality observed 4 h after treatment with the liquid sample.