Abstract
Three-year results of studies on the effect of fertilizing nitrogen fertilizer on the content of amino acids in the grain of sweet sorghum of Kazakhstanskoe 16 and Kazakhstanskoe 20 varieties on irrigated light chestnut soils of the southeast of Kazakhstan are presented.Nitrogen fertilizers are one of the effective means of increasing the protein content of sweet sorghum. The later nitrogen is introduced as a second fertilizer in a dose of N50 in the period of its vegetation, the more effective its effect on the increase in the protein content of the grain. The amount of nitrogen introduced into the soil is of great importance. The number of essential amino acids in sweet sorghum depended on the norms of applying nitrogen fertilizers. The higher is the norm of nitrogen, the more it accumulates in the grain of the protein. At the same time, when nitrogen was added in two terms, the number of such essential amino acids as valine, leucine, isoleucine, and threonine increased significantly, which increases the biological value of the total protein. Therefore, it is possible not only to increase the yield, but also to increase the collection of protein from a unit of area by scientifically substantiating the use of nitrogen fertilizers for sweet sorghum.