Variability of elements of yield structure and yield of winter wheat varieties depending from pre-sowing calibration

The article substantiates the need to improve the elements of technology for growing varieties of soft winter wheat, taking into account the size of the seed material and weather conditions of the growing season. It is determined that along with varietal properties, the use of pre-prepared seeds for sowing has an impact on its sowing properties, field germination, growth and development of plants, their formation of elements of productivity and grain yield. The study was conducted on five registered varieties of soft winter wheat 'Tsarychanka', 'Karmelyuk', 'Sidir Kovpak', 'Dykanka' and 'Sanzhara' in the agro-climatic zone of the central part of the Forest-Steppe of Ukraine. The results of research showed that the highest field germination of seeds have the variety 'Karmelyuk' for sowing shallow and medium fraction of seeds (94 and 90%, respectively), and the variety 'Dykanka' - sowing medium and large fraction (95 and 86%, respectively). The percentage of germination of seeds of varieties 'Tsarychanka', 'Sanzhara' is almost at the same level 82 and 89, respectively. The highest indicators of elements of structure of an ear are found at the varieties 'Karmelyuk' - 30,5 pieces of grains in an ear, for its weight in an ear of 0,86 g, 'Dykanka' - 30,6 pieces of grains in an ear, for its weight in an ear 0, 87. The use of seeds of the middle fraction for sowing provided the highest yield of varieties 'Karmelyuk', 'Dykanka' which amounted to 4.7 t / ha. When sowing seeds of a large fraction, the highest yields were obtained by 'Dykanka' and 'Sanzhara' varieties - 4.8 and 4.9 t / ha, respectively. The aim of the study. To determine the influence of seed fraction on sowing qualities, variability of yield elements of soft winter wheat varieties. The experiment was conducted in the central forest-steppe of Ukraine, using general research methods studied in agronomy The material for the study were winter wheat varieties of Poltava State Agrarian Academy: "Tsarchanka", "Karmelyuk", "Sidir Kovpak", "Dykanka" and "Sanzhara". Sowing of the studied varieties was carried out with seeds selected on sieves and divided into fractions: shallow (1), medium (2), large (3), and mixture (4). Agrotechnics in the study are generally accepted for the soil-climatic zone of the Forest-Steppe of Ukraine. The increase in the weight of 1000 grains was significantly influenced by sowing with the middle fraction of seeds, which is characteristic of the variety 'Sidir Kovpak' (50.4 g), large - 'Tsarychanka' (52.5 g), 'Dykanka' (49.2 g) and 'Sanzhara' (48.4 g), for the variety 'Karmelyuk' the weight of the grain increases when sown with a mixture of seeds (52.0 g).