Study of grain yield and its components in corn hybrids in two planting dates using different rates of biofertilizers in Karaj region, Iran

In order to evaluate the yield and grain yield components of corn hybrids in two successive planting dates under Karaj conditions, two experiments were conducted at Seed and Plant Certification and Registration Institute (SPCRI). The experiments were carried out in a split plot design based on randomized complete blocks with four replications. In this research, five levels of biofertilizers (control, three different levels of Humiforte, Aminol-forte, fosnutren and kadostim and also a combined level of Aminol-forte-Humiforte and kadostim-fosnutren) were arranged in main plots and three maize hybrids (including SC704, SC500 and SC260) were regarded as the sub-plots. Some traits such as grain yield, grain row number, grain number/row, 1000-grain weight and total grain number/ear were studied. The results of variance analysis in the first planting date disclosed that the effects of different fertilizers, different hybrids and also their interactions on grain yield were not significant, while the results of second planting date showed that different corn hybrids had significant effects on grain yield. Mean comparisons of two successive planting dates revealed that the cultivar 704 produced the highest yield (14.31 and 14.17 t/ha, respectively).