Phytohormonal regulatory mechanism of the ontogenesis of heteroderides' activation and synchronization.
Studies using the developed device confirmed the attractive properties of the aquatic extracts of host plants, as well as the high trophic receptivity of the invasive larvae of cyst nematodes. The greatest stimulation of the release and active migration of larvae from cysts was observed when phytoncids were introduced by cultivated host plants at a distance of 2.5-5 cm from the object of study at an optimal humidity of 60-70% of the total soil moisture content. At the same time, the aqueous extracts of the roots of the initial phases of plant growth and development compared to the extracts of the subsequent organogenesis phases were the most attractive. We believe that the larvae react most to the increased content of phytohormones, cytokinins, because their synthesis in comparison with other growth activators mainly occurs in the root system of plants. Nematode isolation of enzymes in plant tissue causes a high content of phytohormones, which are catalysts for the formation of new young roots, thereby providing optimal conditions for the invasion and development of next-generation larvae. Certain stimulating effect was also shown by extracts from other plant organs, which indicates the integrity of the flow of all physiological processes in the plant organism. Due to the genetically fixed mechanism of activation and suspension of physiological processes, a clear synchronization of the ontogenesis of cyst nematodes in accordance with the organogenesis of host plants has been noted. Since the development of heteroderides occurs only in one plant populated by them, sedentary phytoparasites react sensitively to changes in the biochemical composition of the plant organism, due to biological aging or adverse factors of different nature, causing their pathology. The perennial cyclical nature of the development of sedimentary nematodes in accordance with the organogenesis of typical host plants caused the formation of their population adaptation.