Investigation of directions of crossing in maize (Zea mays L.)

Abstract

In Hungary, we examined eight features of twelve direct cross hybrids over a period of three years. The twelve hybrids were derived from direct and reciprocal crosses of four parental lines. We did not find significant differences in the cases of stalk diameter and leaf number in the average of 3 years in any of the hybrids. Statistically explainable differences in primary branches were observed in hybrids UDH5 and UDH8 and also in UDH6 and UDH11. It was evident in both instances that degrees of heterosis in reciprocal crosses far exceeded those of direct ones. High tassel branch number was dominant over the low one; consequently, parents with higher tassel numbers enforced their effects during the formation of this trait in hybrids. We experienced positive correlation (r=0.67**) between plant height and main ear height. A positive correlation (r=0.89**) was also found between the tassel length of the main axis above the lowest and the upper side branch. We observed a medium correlation (r=-0.42**) between the number of primary lateral branches and plant height. The number of primary lateral branches showed the highest heterosis. These results can be utilized in practical selection and seed production.