Abstract: The principal aim of breeding and seed production in Serbia is to provide sufficient amounts of all seed categories of the most productive hybrids for national needs and export. Climate conditions in Serbia are favourable for maize seed production (soil quality, effective precipitation sum, long freeze-free periods, etc.). The introduction of sterile forms of parental lines in the development of seed material of maize hybrids has resulted in the improvement of maize growing practices and provided easier control of seed crops. Therefore, the objective of the present study was to observe the optimum ratio of sterile to fertile hybrid variants for the commercial maize production and their effects on yields. The trial was set up according to the randomise complete block design with three replications. The elementary plot size amounted to 5.18m². The used material consisted of seed mixtures of 0, 5, 10,… to 100% fertile plants mixed with the sterile variant of the observed hybrid. Upon processing of obtained results, the highest yield of 17.341 t ha-1 was recorded in the fertile to sterile variant ratio of 80%: 20%. The coefficient of correlation points out to a low correlation of yields on fertility percentage (rxy=0.164). Furthermore, based on the coefficient of determination, a low percentage of dependence of yields on fertile plants percentage was established (R²=0.027).
Keywords: cytoplasmic male sterility, maize, yield