Sorghum is the agricultural crop most adaptable to the effects of abiotic factors, able to tolerate prolonged soil and air droughts, changes in air temperature, insufficient precipitation, salinization, acidification of soils, and many others with the least loss of yield compared to traditional crops such as wheat and barley. However, even among sorghum genotypes, there are samples with varying degrees of resistance to stressors, for example, drought. The aim of this study is a comprehensive study of the influence of abiotic factors on the physiological characteristics and biochemical parameters of sorghum grain. The experiment was carried out on the experimental field and laboratory conditions of the Rossorgo Institute. Drought resistance of plants is determined in the initial phase of development and during the flowering period by the degree of seed swelling in hypertonic solutions and the water regime of the leaves (total water content, water deficiency, moisture loss, and water-holding capacity). The quality of the grain is determined using the spectrophotometry method for the main biochemical components, and likewise, the separation of the protein into fractions. The growing conditions of plants in 2021–2022 differ significantly in terms of hydrothermal indicators. As a result of the conducted research for use in breeding programs for the creation of new varieties and hybrids with increased stress resistance selected samples L-65/14, Magistr has high drought resistance in the degree of seed swelling in hypertonic solutions (55.2–58.9%), which turned out to be at the level of the control variant (61.6–63.7%), and indicators of the water regime of the leaves (total water content of leaf tissues—74.20–77.83%; water-retaining capacity—83.77–85.56%; low moisture loss for 1 h/day—2.86–3.01%). These samples were characterized by the biological value determined by the optimal ratio of major indicators of grain and protein fractions: albumin (16.59–22.75%), globulin (8.13–9.09%), glutelin (9.09–14.01%), and prolamin (5.79–11.50%).

One of the promising areas of fundamental and applied research is the study of plant stress resistance using natural and synthetic physiologically active substances. An increase in the germination capacity of plant seeds and the rate of their germination is achieved by treatment before sowing with aqueous solutions of biostimulants, which leads to the activation of biochemical processes, increases the energy of germination, and improves seed germination in conditions of increased soil salinity. The effect of the bacterial exopolysaccharide (EPS) of Streptococcus thermophilus in the form of a film coating on the stress resistance of sorghum (RSK Partizan, Volzhskoe 44, Zhemchug and RSK Onyx) was studied, the seedlings and roots of treated seeds were compared against seeds without treatment. A positive effect of the exopolysaccharide film was found at the early stages of plant development under conditions of an increased salt content in the soil (2% and 4%), which was expressed in an increase in the length of seedlings and roots.

The article discusses the results of a study of the biochemical composition of sorghum grain of varieties of selection of the Russian Research and Design Technological Institute of Sorghum and Maize. The main parameters that characterize the biological value of grain crops have been studied: protein, fat, minerals, fiber, nitrogen-free extractives, including starch. The varieties containing the greatest amount of protein and sugars were identified, and recommendations were given for their further use in the agro-industrial complex.