Abstract. Legumes play a leading role in providing farm animals with high-quality and highly nutritious feed, while in the Lower Volga region, the traditional alfalfa crop plays a leading role. The productivity of alfalfa in production conditions is only a tenth of its potential. The purpose of the research is to determine the impact of reduced seeding rates, varietal characteristics, seeding time and use of siderates instead of mineral fertilizers on the seed productivity of the crop. The field experience included 2 terms of sowing – spring and summer, 3 variants of the soil nutrient regime: the natural background of nutrition and plowing of two types of sideral mixtures (sunflower + vetch and oats + radish); three variants of the density of herbage (40, 80 and 400 thousand plants/ha). Observations were made on three varieties of alfalfa (Leninskaya mestnaya, Vega 87 and Unitro). Records and observations were made in accordance with the generally accepted methods of experimental work. Results and practical significance. As a result of research, a favorable influence of sideral masses on the formation of a symbiotic apparate on alfalfa roots was revealed. In comparison with the natural background of nutrition, the number of nodules significantly increased in the variants with the plowing of siderates. The yield of seed alfalfa was also influenced by the density of sowing. More productive organs were formed in sparse grass stands, which contributed to an increase in the collection of seeds. The use of sideral mixtures also had a positive effect on productive shoot formation. The number of stems, brushes and seeds in the bean was 25–30 % more than in the control. Summer sowing favourably affected the seed productivity of alfalfa, its indicators were 1.2–1.6 times higher than the data obtained from the grass stands of the spring sowing season. Scientific novelty. For the irrigated conditions of the Lower Volga region, a comprehensive assessment of the participation of the main agrotechnical techniques in the implementation of alfalfa seed productivity is given: terms, methods and seeding rates with the use of siderates for soil fertilization.
Processing of specific growth of various potato varieties under drip irrigation in Lower Volga region
