In the conditions of the Donbass region, 38 varieties of grain sorghum of various ecological and geographical origin-breeding companies of Western Europe (“RAGT SEMENCES”, “EURALIS SEMENCES”, “PIONEER”), Ukraine, Russia, the international company “ADVANTA”, the American company “RICHARDSON SEED” were studied. Field research was carried out in the period from 2016 to 2018 in the experimental field of the Lugansk National Agrarian University on ordinary shallow weakly washed blackearth (chernozem) on loess-loam. It was found that the most adapted and productive (6,0 t/ha of grain or more) were early – maturing hybrids – Swift and Queyras; middle early – Solarius, PR88Y20, Bianca, Puma Star; mid-season - Bounty. The most productive (5,0 t/ha and more grain) varieties – Odessky 205, Krupinka 10, Darunok, Zersta 97. The average positive correlation between the duration of the growing season of varieties and crop yield was established. The density of the productive stem in the range from 11 to 25 panicles per 1 m2, the length of the panicle leg and the weight of 1000 grains did not have a significant correlation with the level of sorghum yield. Sorghum yield had an average and increased correlation with panicle weight, grain weight per panicle, number of grains per panicle, grain type, and medium negative relationship with plant height.

Global warming is currently having a measurable effect on Earth, so the process is bringing about significant changes in weather conditions during the vegetation period of the main field crops. This is true for the arid steppe conditions of the Donbass territory. The authors conducted a field experiment to evaluate climatic factors' effect on the productivity of various early maturing grain sorghum hybrids on ordinary chernozem in Luhansk National Agrarian university's experimental field 2015–2019. The study obtained the strongest direct correlation between the yield of hybrids and the amount of precipitation for April – September (r = 0,84–0,99) or only correlated with precipitation for August (r = 0,75–0,98). A moderate and high correlation was found between the yield of hybrids and the hydrothermal coefficient (HTC) for April – September (r = 0,53–0,89) and a high correlation with the HTC for August (r = 0,67–0,99). The average monthly air temperature in summer did not show a significant correlation with the sorghum yield. The crop yield had an average (r = 0,52–0,66) and strong (r = 0,90) direct correlation with the mass of 1000 grains, a strong correlation (r = 0,92) with the height of plants, and a strong correlation (r = 0,76–0,99) with the duration of the vegetational season of sorghum. The early-maturing hybrid Yankee and the medium-early maturing hybrid Puma Star showed the closest correlation between the sorghum crop and the amount of precipitation for August (r = 0,91–0,98) and the Selyaninov HTC for August (r = 0,87–0,99). In 2015–2019, the Puma Star hybrid demonstrated the highest grain yield, significantly higher than other hybrids (56,5–77,6 C/ha), due to the higher grain weight obtained from the panicle (42,5–49,8 g) and the weight of 1000 grains (21,8–28,2 g). The Puma Star hybrid showed an extreme dependence of the yield on the mass of 1000 grains (r = 0,96 ± 0,01).

Abstract. The purpose of the work is to establish the effectiveness of weed in control in crops of grain sorghum with herbicides of soil and leaf action. Scientific novelty. For the first time in sorghum crops for weed control, effective combinations of soil and leaf herbicides have been identified. Methods. Experiments were carried out on the black soils of steppe zone Ukraine. Research methods are generally accepted. The control options were herbicide-free and weed-free. Results. At tillering stage the number of weeds in sorghum crops reached 141 pieces/m2 and their air-dry weight was 218 g/m2. Green amaranth (Amaranthus retroflexus), fat hen (Chenopodium album), field mustard (Sinapis arvensis), ragweed ragweed (Ambrosia artemisiifolia), barnyard grass (Echinochloa crus-galli), bristlegrass (Setaria viridis) were dominant in the crops. The use of foliar-applied herbicides such as Agritox (1 l/ha), Ballerina (0.4 l/ha), Dialen Super (0.7 l/ha) in the stage of three-five leaves and a pre sowing soil-applied herbicide Primextra Gold (3 l/ha) ensured the maximum reduction of weed infestation of grain sorghum crops. The number of weeds with the use of these herbicides decreased by 10.4–19.7 times, and their weight decreased by 4.1–4.8 times in comparison with the options without the use of weed control measures. The conditions for plant growth and development were improved due to the reduction of weed infestation of grain sorghum crops. The growing period of the crop reduced from 125 to 114 days, the height of plants increased by 19–21 cm and their weight increased by 2.7–2.8 times. The sorghum grain yield reached 6.32–6.34 t/ha, which was higher than with the options without the use of weed control measures by 4.01–4.30 t/ha or 3.0–3.1 times. The same results were obtained in production conditions.