Productivity of the Syniukha variety alfalfa grass stands of the fourth and fifth years of growing in conditions of the northern Podillia

Purpose. To evaluate the productivity of feed grass stands of the Sinyuha variety alfalfa according to yield indicators, quality and nutritional value of green mass harvested in the phases of budding and flowering to establish their value for the use in livestock industry in conditions of northern Podillia. Methods. Field experiment (visual and phenological observations of the growth and development of alfalfa plants), calculation, thermostatic, mathematical-statistical. Results. The studies were carried out in the field experiment of the Khmelnytskyi state agricultural research station of the Institute of Feed Research and Agriculture of Podillya of NAAS during 2019-2020 on podzolized medium loam black soil. The optimal phase of mowing alfalfa in the feed grass stands of the fourth-fifth years of life was determined. It is the budding phase, in which the feed productivity of the crop increased: the yield of green mass in the sum of four mowings, which was 2.5 t/ha or 5% higher. Despite a slight difference in dry matter content, its total yield was practically equal to that of the flowering phase. The studied phases of mowing had an impact on the feed productivity of alfalfa. It has been established that, in terms of quality and nutritional value of the leaf-stem mass, a greater accumulation of nutrients occurred during the mowing of alfalfa in the budding phase, when the gross yield of the sum of cuttings was: feed units – 8.78 t, crude protein – 2.39 t, gross energy – 151.52 GJ and exchange energy – 92.12 GJ. Conclusions. To ensure high yields and good feeding qualities of the Sinyukha variety alfalfa grass stands of the fourth-fifth years of cultivation in conditions of northern Podillia, mowing in the budding phase should be applied, what will contribute to the increase in the total yield of green mass with a slight difference in the total dry matter yield and increase in gross yield: feed units, crude protein, gross and metabolizable energy relative to the flowering phase.