Topicality of the issue. Grain sorghum is one of the most important food and forage crops. It is used under conditions of the South of Ukraine in main crops and for resowing perished winter and spring crops, and it has a considerable propagation coefficient. Thus a special significance is ascribed to the research on developing basic techniques of growing grain sorghum in the Southern region of Ukraine.
The purpose and goals of the research: to increase grain sorghum productivity under non-irrigated conditions of the South of Ukraine by optimizing the nutrition area of the plants with different sowing times and identifying sorghum hybrids which are the most adapted for the conditions of the region.
Conditions and methodology of conducting the research. The experiments were carried out in 2013–2015 according to the generally accepted methodology, the experimental plot was 50 m2, the experiment was repeated four times.
The results of the research. The grain sorghum hybrids under investigation (Sontsedar, Praim, Burhho, Sprynt W, Dash-Е, Tarhho) are perspective for growing under arid conditions in the South of Ukraine. In 2013–2015 the maximum yield of 6.69–6,54 t/ha was supported by the hybrids Dash-E and Sontsedar with the early sowing time and the sowing density of 180 and 140 thousand per hectare. At the late sowing time the highest grain productivity of 3.96 t/ha was achieved by the hybrid Dash-E with the crop density of 180 thousand per hectare, and Sontsedar had the highest yields with the crop density of 100 thousand per hectare – 2,67 t/ha. The application of succinic acid for treating the crops in the phase of panicle development results in increasing grain sorghum yields at the level of 12–15% and accelerates grain maturity by 7–8 days.
Conclusions. The research shows that sowing times and crop stand density influence the productivity of grain sorghum hybrids in a different way. In all the cases grain sorghum of the early sowing time has stably high yields as compared with that of the late sowing time.
The application of succinic acid for treating the crops in the phase of panicle development results in increasing grain sorghum yields at the level of 12-15% and accelerates grain maturity by 7–8 days.
Key words: grain sorghum, yielding capacity, hybrid, sowing time, sowing density, succinic acid.