Response of soybean varieties to climatic challenges in the conditions of the North-Eastern Forest-Steppe of Ukraine

Abstract

Climate change, which is currently changing, significantly affects the productivity of agricultural production in general and forms new directions for the development of the agricultural sector of Ukraine. It is known that the leading source of vegetable protein and oil in the world is soybean (Glycine max (L.) Merrill.). We can explain the high demand for this crop by its economic efficiency. In addition, about 380 kg of oil are harvested from the same area, the sale of which provides a return on almost all cultivation costs. Soybean is capable of satisfying its own nitrogen needs by 60–85 %, and the excess that remains in the soil makes it a valuable precursor in crop rotation. The crop can be grown in spring, post-cut, post-harvest crops, and also used as insurance when reseeding winter crops. However, there is a scientific position that obtaining consistently high soybean yields is possible mainly within the so-called “soybean belt”, where agroclimatic conditions are favorable for its production. At the same time, taking into account the impact of climate change and developing effective adaptation strategies make it possible to expand the area of soybean cultivation beyond the traditional regions. The effectiveness of soybean varieties cultivation largely depends on geographical latitude: shifting the area by one degree, approximately 100–160 km, requires the creation or introduction of a new variety. Moving varieties bred for one zone to other regions often leads to changes in plant height, the duration of the growing season, the number of beans and the level of yield, which makes such specimens unsuitable for industrial cultivation, therefore, the systematic import of seeds of foreign selection, not adapted to local conditions, may cause serious agricultural problems in the future. In Ukraine, soil and atmospheric droughts are often observed, which act as powerful stress factors for soybean. The low adaptive plasticity of the genotypes used as the starting material for breeding negatively affects seed productivity.