THE ROLE OF SEED FRACTIONS AT FORMATION OF SPRING SOFT WHEAT PRODUCTIVITY IN MODERN CULTIVATION TECHNOLOGIES
The analysis of seed sowing influence of different fractions on the main economic-valuable traits of modern varieties of spring soft wheat breeding institutes of the FPBSI Volga RISS was carried out during the research years (2015-2017). As an object of research, four modern varieties of the breeding institute, included in the State register of breeding achievements of the Russian Federation, were used: Kinelskaya niva, Kinelskaya otrada, Kinelskaya 2010, Kinelskaya yubileynaya. Four variants of different fractions of seeds were studied (a gathering with sieve, mm): 2,0х20 mm, 2,3x20 mm, 2,5х20 mm, 2,8x20mm. The role of separate fractions of seeds in formation of productivity of the zoned grades of spring soft wheat of various genotype was noted. The criteria for selecting and adjusting the optimal of seed fraction depending on the conditions of cultivation and the genotype of the variety were defined. According to the results of the research, for the formation of higher yields of new varieties of spring soft wheat of breeding institute, farmers of the middle Volga region were recommended to use larger and aligned fractions for planting depending on the genetic characteristics of the variety. Herewith, to obtain the highest yields, the minimum fraction when preparing seeds in any year should provide a mass of 1000 seeds of the Kinelskaya otrada variety more than 37,0 g, Kinelskaya niva – 38,5 g, Kinelskaya yubileynaya – 39,0 g, Kinelskaya 2010 more than 39,5 g. The use of optimal seed fractions for sowing is an important agrotechnical technique to increase the yield of spring soft wheat and reducing the direct costs of seeds. The data obtained are recommended to improve the elements of cultivation technologies of grades in the region.