GENETIC AND PHYSIOLOGICAL CHARACTERISTICS OF EXTRA-LARGE GRAIN IN BUCKWHEAT

Large grain is a desirable feature for the production of buckwheat groats. The possibility of its increase is obviously limited, but not known precisely. To study the inheritance of extra-large grain in buckwheat, we carried out self-pollination of self-fertile large-grain plants from a population of hybrid origin (large-grain variety Troyanda × homostyly HL1), with further ranking by seed size and analysis of the progeny. At the beginning of ripening, shoots with seeds were cut off from the selected plants: the cross-pollinated seeds were used as a control. Other shoots on these plants were isolated after removing of both all open flowers and developing seeds. 226 the self-pollinated plants were divided into 6 groups according to the weight of 1000 seeds (M1000): 1) M1000 < 30 g (14 plants), 2) M1000 = 30-34.9 g (44 plants), 3) M1000 = 35- 39.5 g (72 plants), 4) M1000=40-44.9 g (38 plants), 5) M1000=45-49.9 g (34 plants), 6) M1000> 50 g (24 plants). Seeds collected from plants within each group were mixed: 6 populations for the analysis were obtained. For the trait “dry plant weight,” the degree of inbreeding depression did not depend on the experimental variant, while for the number and weight of fruits per plant, the decrease in the values of the traits was more significant in the largest-grain variants. In our experiment, the limit of the weight of 1000 seeds, exceeding which leads to a sharp decrease in the grain productivity of the plant, is at 40 g. In practical breeding, this value is much lower. The significant dependence of inbreeding depression for M1000 on the value of this trait indicates a strong dependence of the manifestation of extra-large grain size on heterozygosity for genes that determine the variability of this trait.