Assessmentof seed productivity of complex hybrid populations of red clover

Abstract

In the conditions of the Kirov region, the productivity of seeds of four complex hybrid populations (SGP) of red clover was studied, including those formed against an infectious fusarium background (SGPF). The research was carried out in the nursery for evaluating the seed productivity of 2017 sowing in comparison with the standard (st.) Dymkovsky for 2 years of use (y.u.). The characteristics of the SGP and SGPF according to winter hardiness, the start of vegetation phases of development, plant height, structure of seedgrass stand, yield and quality of seed material are given. All studied varieties were more productive than the standard (1.97 c/ha). Reliably high seed yield on average for 2 years was shown by SGPF-158-3 – 2.48 c/ha, SGP-188 – 2.32 c/ha, SGPF-157-3 – 2.16 c/ha. According to fruiting indicators, in 2019SGPF-158-3 with small heads, but with the largest number of flowers and seeds (132.2 and 77.4 pcs., respectively), good seediness (58.8 %) and high seed weight per head (0.153 g) was selected. Also, high rates were noted in the populations of SGPF-157-3 and SGPF-160-3. A strong correlation between seed yield and fruiting rates was revealed: the number of flowers in the head (r = 0.92), the total number of seeds in the head (r = 0.92), the number of filled seeds in the head (r = 0.94), the seediness of the head (r = 0.90), the total weight of seeds in the head (r = 0.85), the mass of filledseeds in the head (r = 0.87). A close positive correlation was noted between the hydrothermal coefficient (HTC) value and length (r = 0.86), width (r = 0.86) of the red clover head during the intergrowth period “regrowth - the beginning of flowering”. It has been established that the average daily air temperature and the sum of effective temperatures during the “beginning of flowering - ripening” period have a positive effect on the fruiting performance: “seediness of the heads” (r = 0.97 and r = 0.87) and “the number of seeds in the head” (r = 0.95 and r = 0.89, respectively). In the same interphase period, a close negative dependence of the indicated fruiting indices on the HTC values was revealed (r = -0.95 and r = -0.94). The sowing qualities of the seeds of the 2019 harvest were determined; it was found that all seed material corresponds to the category of “original and elite seeds”. As the result of the research, the populations of red clover SGPF-158-3, SGP-188 and SGPF-157-3, superior to st. Dymkovsky on seed productivity (by 0.51; 0.35 and 0.9 c/ha, respectively, LSD05 = 0.12 c/ha) and fruiting indicators, were selected.