The microbial activity and phytosanitary condition of sunflower crops depending on the levels of biologization of cultivation technology

Abstract

The research was carried out from 2018 to 2021. The field experiments were conducted in four replications by using the split-plot design method. The study evaluated the following cultivation technology elements: A – sunflower hybrid: A1 – PR64F66 F1; A2 – Tunca F1; B – cultivation technology: B1 (traditional); B2 (biologized І); B3 (biologized ІІ); B4 (organic); B5 (extensive). The research showed that during the growing season, under intensive sunflower cultivation technology, both the total colonization of the arable soil layer of the research plot and the amount of microflora by certain most principal groups decreased considerably compared to the variants where some elements of biologization or their complex application (organic cultivation technology) were implemented by 6.1–40.9%. The application of modern insecticides of organic origin in sunflower plant protection under biologized and organic cultivation technologies allows controlling a whole array of the most harmful phytophages and is not inferior to synthetic insecticides in effectiveness. The exception is the protection of the crop against owlet moth larvae, which, because of their biological and ecological characteristics, require an insecticide with more systemic properties, which are not characteristic of organic preparations with few exceptions. Biological preparations had no residual insecticidal or repellent effect on major crop pollinators. The application of pre- and post-emergence harrowing with harrows and rotary hoes and inter-row tillage in the system of the crop protection against weeds as a component of biologized and organic technologies for sunflower cultivation is as effective as soil and post-emergence synthetic herbicides.