Object of the study – processes of growth, development, formation of crop yield and grain quality of sorghum varieties and hybrids depending on sowing methods, plant density, application of fertilizers and herbicides in the Northern Steppe of Ukraine. The aim of the research – to scientifically substantiate existing and develop new effective technological methods to increase the crop yield of sorghum plants, taking into account changes in weather factors, morphobiological characteristics of varieties and hybrids, their response to the use of fertilizers and herbicides at different sowing methods and plant densities. Research methods – general science: analysis and synthesis, generalization and systematization; visual – when conducting field observations; measuring and weight – for crop accounting and determination of plant biometrics; mathematical and statistical – to determine the reliability of the results, the correlation dependence of the impact of technological measures, calculations of economic efficiency. Results – in conditions of insufficient moisture of the Northern Steppe of Ukraine in order to increase the realization of adaptive and genetically determined potential of grain sorghum productivity with high grain quality and economic efficiency of production, it is recommended to apply the following optimized technological measures of its cultivation: to sow high-yielding and plastic varieties – Dniprovs’kyi 39 and Vinets’, and hybrid Prime; to sow with a row spacing of 45 and 70 cm the seeds of the variety Dniprovs’kyi 39 and the hybrid Prime for plant stand densities of 140 thous. pcs/ha, and the Vinets’ variety – for densities of 160 thous. pcs/ha; to apply the insurance herbicide Peak at a dose of 20 g/ha in grain sorghum crops, which provides a decrease in weed level by 89,3 % and an increase in grain yield by 1,4 t/ha; to apply mineral fertilizers (N60P60K30), which contributes to the increase in grain sorghum crop yield of 0,76–1,02 t/ha. Novelty – for the first time the optimal methods of sowing, density of standing plants per unit area for varieties Vinets’, Dniprovs’kyi 39 and hybrid Prime were researched and scientifically substantiated; the optimal dose of mineral fertilizers for variety Dniprovs’kyi 39 and hybrid Kovcheg has been established; determined the most effective post-emergence herbicide with minimal phototoxicity for sorghum plants; the peculiarities of the formation of crop yield and grain quality of different varieties and hybrids of grain sorghum under the influence of the studied agro-technological measures and hydrothermal conditions in the Northern Steppe are substantiated; the economic estimation of efficiency of the optimized technological measures of cultivation of grain sorghum is carried out. The technology of grain sorghum cultivation has been improved by combining the interaction of factors – variety/hybrid, mineral fertilizers, sowing method, plant density, herbicide protection of plants in the Northern Steppe. Scientific approaches to the formation of varietal agricultural measures for growing grain sorghum have been further developed; economic and bioenergy assessment of the feasibility of implementing optimized technological measures for growing different varieties and hybrids of grain sorghum. Field – agricultural sciences.
