Effect of fertilizers on the grain yield and quality of grain sorghum

Abstract

Purpose. To study the influence of mineral and alternative organic-mineral fertilization systems on the yield and quality of grain sorghum.Methods. Field, analytical and statistical.Results. The results of studies on the effect of doses of mineral fertilizers and their combined application with winter wheat straw on the yield and quality of grain sorghum are presented. It was found that under the conditions of sufficient moisture on the light-loamy leached black soil, the application of fertilizers significantly increased the yield and quality of sorghum.Conclusions. The application of fertilizers has enhanced the growth and development of the leaf surface of sorghum plants. In the case of fertilizers application, the leaf area in the phase of tassel ejection was 0.23–0.27 m2/plant, full ripeness 0.15–0.17 with an excess to the control without fertilizer by 0.01–0.05 and 0,01–0.03 m2/plant, respectively. The maximum leaf surface was observed in the tassel ejection phase for the application of mineral fertilizers N120Р120К120 or their combination with 4 t/ha of straw: leaf area 0.26 and 0.27 m2/plant, respectively. The application of fertilizers for grain sorghum under the conditions of sufficient moisture on the light-loamy leached black soil increased grain yield compared to the control without fertilizers by 12–39%. The highest nutritional productivity of grain sorghum was achieved by an alternative organic-mineral fertilization system (straw 4 t/ha + N120Р120К120): grain yield of 8.5 t/ha with an excess to the fertilizer dose N120Р120К120 by 0.6 t/ha, control without fertilizers by 2.4 t/ha. The application of fertilizers significantly improved the quality of sorghum grain, increasing the protein content in the grain by 0.5–1.8 %, fat by 0.08–0.20 % of dry matter, weight of 1000 grains by 1.6–4.9 g. The highest quality of grain was observed for the application of straw 4 t/ha + N120Р120К120: weight of 1000 grains of 33.0 g, protein content in the grain of 12.1 %, fat of 3.59 % of dry matter.