Components of genetic variability of ear length of silage maize

The objective of this study was to evaluate following parameters of the ear length of silage maize: variability of inbred lines and their diallel hybrids, superior-parent heterosis and genetic components of variability and heritability on the basis of a diallel set. The analysis of genetic variance shows that the additive component (D) was lower that the dominant (H1 and H2) genetic variances, while the frequency of dominant genes (u) for this trait was greater that the frequency of recessive genes (v). Furthermore, this is also confirmed by the dominant to recessive genes ratio in parental inbreds for the ear length (Kd/Kr is greater than 1), which is greater than unity during both investigation years. The calculated value of the average degree of dominance is greater than unity, pointing out to superdominance in inheritance of this trait in both years of investigation, which is also confirmed by the results of Vr/Wr regression analysis of the inheritance of the ear length. As a presence of the non-allelic interaction was established it is necessary to study effects of epistasis as it can have a greater significance in certain hybrids. A greater value of dominant than additive variance resulted in high broad-sense heritability for ear length on both investigation years.