The influence of chitosan-based environmentally friendly agents on the phytosanitary condition of potato plants and crop productivity in Western Siberia

Induction of plant immunity to harmful organisms using biologically active substances with elicitor (signal) action is the most promising modern method of plant protection. Among them, chitosan-based agents are widely used, their effect is manifested in an increase in disease resistance by 30–40 %, an increase in biosynthetic processes of formation of amino acids and vitamins, growth stimulation, which increases crop productivity. In potato growing, a serious problem, in addition to fungal infections, is the accumulation and transmission of bacteria and viruses in crop plantings, what leads to significant yield losses (25–75 %). Moreover, there are no antiviral and antibacterial drugs for use in potato production. At the same time, chitosan and other biologically active substances, having a wide range of unique biological activities, for example, have the ability to induce resistance to both fungal and viral diseases of plants. Therefore, one of the areas for improving potato production, its quality, stabilizing the phytosanitary condition of crop plantings can be the expansion of the range of biologically active substances and the improvement of the methods of their use. The study of the effect of new environmentally friendly chitosan-based agents on the phytosanitary situation in potato plantings and productivity indicators in the conditions of Western Siberia showed that they increased crop germination by 16.0–68.0 %, reliably increased plant length by 3.2–18.1 %, plant weight by 11.1–24.8 %, and the number of stolons and tubers by 14.8–73.2 and 8.0–43.2 %, tuber weight by 8.2–25.8 %. These agents reduced the development of rhizoctonia in the seedling phase by 6.7–14.6 %, the prevalence of macrosporiosis from 10.0 to 30.0 %. With a hundred percent spread of late blight, its development at the initial stage of damage had differences and was less than in the control. Its minimum development (by 1.5 points, control 2.8 points) was noted in the case of treating planting tubers with agents No. 1, 7, 8 and 12, and treating plants during the growing season with agent No. 1. When using a combination of agents No. 7 (treatment of tubers) and No. 12 (spraying plants), viros is in crop plantings was completely absent. The crop yield when using new agents varied on average over three years from 14.5 to 20.0 t/ha, the yield increase was from 1.4 to 6.9 t/ha (from 10.7 to 52.7 %).