Yield of grain sorghum depends on fertilizer and varietal characteristics

Abstract

Grain sorghum (L.) is a valuable crop with high yields. The crop future perspective depends on the ability of producers to apply optimal growing technologies. The general prerequisite for high yields of sorghum crops is the most efficient satisfaction of plant needs during the growing season, that is, the use of necessary chemical nutrients. Sorghum yields can be significantly increased by providing adequate nutrients. Fertilizer management affects not only yield but also the quality of the final product. Providing sorghum crops with adequate doses of fertilizers assist in maximising of yields. That is, research is needed on the selection of sorghum varieties optimal for the growing zone and the application of appropriate elements of technology, in particular, determining the optimal rates of mineral fertilizers that can ensure high yields in the northeastern forest-steppe zone of Ukraine, which was the goal of our research. The research was conducted during 2021-2023 at the educational and scientific field of Sumy National Agrarian University. The experiment repetition was trice, the plot placement was systematic. Factor A – hybrid and varieties of grain sorghum: Yankee, Dniprovsky 39, Samaran 6. Factor B – fertilizer rate: variant without fertilizer application (control), Nitroammophos (N16 P16 K16 ), (N35 P35 K35 .) and (N70 P70 K70 ) active ingredient kg/ha were applied for pre-sowing cultivation. The results showed that the use of fertilizer rates of N70 P70 K70 and N35 P35 K35 increased sorghum yield from 2.30 to 6.32 t/ha depending on genotypes. With increasing fertilizer rates, the value of the yield coefficient and crop weight increased. The highest yield coefficient was determined for the Yanki hybrid and the Samaran 6 variety with an average coefficient value of 35 – 37%. (fertilizer rates of N70 P70 K70 and N35 P35 K35 ) For Dniprovsky 39 and the Samaran 6 variety, the maximum level of yield increase was noted with application of N35 P35 K35 – 11, 8 kg and 5,52 kg of grain per 1 kg of active substance, respectively. For Yankee hybrid, the highest indicator values was 11.90 kg of grain per 1 kg of active substance with a maximum rate of N70 P70 K70 . In general, for high level of yield, the optimal rates of fertilizer application were N70 P70 K70 and N35 P35 K35. The yield of Yan kee hybrid and the Dniprovsky 39 variety was the highest in the experiment so they could be recommended for the growing under region conditions.