Influence of non-fallow predecessors on yield of winter rye (Secale cereale L.) in the northern Steppe of Ukraine

The research results of influence of non-fallow predecessors on growth, development and formation of productivity of winter rye plants in the northern Steppe of Ukraine are given. It was found that higher grain yields (6.55 t/ha) were formed due to sowing dates from 20 to 25 September of Stoir winter rye variety after spring barley. Sowing winter rye after sunflower significantly reduced morpho-physiological indicators of plants that resulted to decrease grain yield. The yield of more plastic Pamiat Khudoierka variety had did not exceed 4.63 t/ha. According to research, higher moisture reserves of 23.5 mm in a meter soil layer were after spring barley on the sowing date of winter rye. In addition, it was determined that the productive moisture soil reserves at the arresting growth season of winter rye plants in autumn depend on the predecessor: after spring barley the amount of agronomically valuable moisture in the 0–20 cm arable layer was 33.6 mm, after sunflower – 28.4 mm. Over the two years of research, it was found that the plant height of the high-yield Stoir variety at the beginning of the winter averaged 23.1 cm, and the number of shoots and nodal roots - 4.6 and 9.3 pcs/plant, respectively. It was established that predecessors and weather conditions significantly influence on the winter rye yield formation. Indicators of structural elements of yield show that stubble predecessor of spring barley dominates over sunflower, and provides better conditions for growth and development of winter rye plants. At the time of harvest, the winter rye spike length averaged 11.2 cm, the number of spikes and grains per the spike – 22.8 and 37.2 pcs, respectively. Key words: winter rye, variety, predecessors, moisture reserves, morpho-physiological parameters of plants, yield structure, yield.