Korniichuk O. Agrobiological bases of stabilization of grain production in the central part of the right-bank forest-steppe of Ukraine.

The dissertation substantiates the scientific and theoretical principles of stabilization of grain production in the conditions of deep climatic and technogenic changes in modern agrocenoses of the central part of the Right-Bank Forest-Steppe. The essence, dynamics and direction of such changes are shown. An increase in frequency and duration of dry periods at all stages of organogenesis of winter wheat was established. The influence of the massive reduction in the livestock industry in the agricultural sector of the economy on modern technologies of growing winter wheat, in particular, on the structure of its predecessors, is emphasized. As a result of such a reduction, a sharp decrease in the number of forage crops, which are predecessors, that leave the field early, was noted, while an increase in crops, which, during late harvesting, remove a large amount of moisture and nutrients from the soil. The growing deficit of soil moisture supply as the main limiting factor in the existing farming systems of the region, the real threat of approaching its hydrothermal conditions to the indicators of the northern Steppe is proved. The effectiveness of the use of post-harvest plant residues for soil needs with a shortage of organic fertilizers of animal origin, the positive role of pre-sowing bacterization of seeds and the use of complex microfertilizers in the nutritional system of winter wheat have been experimentally established. For the first time in the conditions of the region and the expediency of using No-till technology of growing winter wheat on gray forest soils of the zone of unstable moisture were investigated and substantiated. Its moisture-accumulating, anti-erosion and humus-forming effect, as well as economic efficiency, are emphasized. It has been established that a significant increase in winter wheat yield is observed starting from the third year of applying zero tillage. It is shown that in connection with the increased risks in growing winter wheat, the importance of corn in stabilizing grain production in the context of modern natural and anthropogenic changes increases. The main parameters of the expediency of expanding the crops in short crop rotation have been substantiated. It was found that on gray forest soils in the zone of unstable moisture, repeated sowing of corn in the same field leads to a decrease in its yield by 0.6 t/ha and is not advisable. Key words: agrocenoses, crop rotation, hydrothermal regime, winter wheat, corn for grain, fertilization system, micronutrient fertilizers, bacterial preparations, No-till technology.