Duration of Seed Grass-Stand Use of Perennial Leguminous Grasses

Abstract

Seed productivity of perennial leguminous grasses is subject to sharp fluctuations due to their biological characteristics, different reactions to changes in growing conditions, and meteorological factors over the growing season. In this case, the productive longevity of herbs is of great importance. The research aims to analyze the seed productivity and the duration of using the grassstand of perennial legume grasses in the meteorological conditions of the Middle Pre-Urals. The analysis of seed yield, energy, and economic efficiency of long-term use of perennial leguminous grasses was carried out based on a result of studies laid down in the Udmurt Research Institute of Agriculture of the UdmFRC of the UB RAS in 1996–2005 with the eastern Galega variety Gale, in 2011–2015 – with varieties of red clover and variegated alfalfa, in 2011–2016 – with birds-foot trefoil variety Solnyshko. The research found that red clover sowing is best used for seeds for one year. In the first year of use, the yield of double-cut clover varieties was 146 kg/ha, of single-cut varieties – 138 kg/ha. In the second year of using the grass stand, the yield significantly decreased to 37 and 39 kg/ha. The yield of 162 kg/ha at the standard level was formed by the twocut clover variety Dymkovsky. Crops of variegated alfalfa can be used for seeds for two years. Seed productivity of variegated alfalfa varieties in the 1st year of use was 204 kg/ha, in the 2nd year of use – 260 kg/ha. Alfalfa of the Guzel variety formed a significantly high seed yield of 251 kg/ha. The recommended duration of the use of the birds-foot trefoil grass-stand is two to three years. In the 1st and 2nd years of use of the grass stand, the yield of the seeds was relatively high, 215–378 and 213–349 kg/ha, respectively. By the 3rd year of use, it decreased to 89–161 kg/ha. The old-age grass stand of the 4th year of use did not form seeds. Sowing the birds-foot trefoil without a cover or under cover of spring wheat by the usual row method with a seeding rate of 8–9 million units/ha showed the highest seed yield of 255–270 kg/ha. The duration of the use of the eastern Galega grass-stand is up to 10 years or more. The highest yield of Galega seeds of 510 kg/ha was obtained during the harvesting of grass in the first year of use for feed, in the second – fifth year of use – for seeds, from the 6th year of use – for feed.