Yield and Yield Components of Different Maize Genotypes Depending on Sowing Density and Weather Extremes

Maize (Zea mays L.) is an important agricultural crop, but its yield often varies due to unfavorable climatic conditions and agrotechnical factors. The research aimed to determine the influence of climatic conditions and sowing density on the number of rows of grains per cob, the thousand kernel weight, the number of plants in the harvest and the grain yield of different maize hybrids. The experiment was conducted in Leskovac, Republic of Serbia, during four growing seasons (2014-2017) on alluvial soil. The research included six maize hybrids from three FAO ripening groups (400, 500 and 600) in three sowing densities (71.428, 57.143 and 47.619 plants per ha). The results show that the sowing density, the hybrid and the climatic conditions significantly influenced the yield components and the total grain yield. The increase in sowing density caused a decrease in the thousand kernel weight and the number of rows of grains per cob. At the same time, above-average temperatures and a deficit of precipitation negatively affected the yield, especially during 2015. The highest yield was recorded with hybrids from FAO group 500, medium sowing density. The results indicate the need for a localized approach in the selection of hybrids and adaptation of agrotechnical measures in order to mitigate the negative effects of climate change.