Abstract: Of great importance for the extension of the practice of corn amelioration, of quantitative genetic analysis methods, was the enunciation of the general combination capacity (CGC) and specific combination (CCS) concept. According to this concept, CGC means the additive genetic component transmitted by a parent to all his offspring and CCS is the genetic component transmitted to the offspring only after crossing a genitor, specifically with another particular partner. These two components are genetically equivalent to the effect of additive gene action for CGC and the effect of non-admissive, dominant + epistaxic gene interactions in the csc case. It can be said that this concept marked spectacular results recorded by the creation of maize hybrids in the second half of the 20th century. The overall ability to combine inbred lines is particularly important in making valuable corn hybrids. Crossing known inbred lines through the general combination ability (for production or other character) in a dialell system, it is normal to perform a hierarchy of the respective inbred lines. The study of the effects of the general combining ability in the expression of heterosis in the characters: the height of insertion, the total height, the length of the ear, the number of grains per row, the grain weight, the weight of the ear, the dry matter, the MMB, the number of erect plants, using experimental data from a dialel system of type p (p-1) / 2. Regarding the analysis of variants of hybrid combinations obtained in the dialell system, it is observed that for all the studied characters the ratio between the specific combining capacity and the overall combinaton capacity is superunit, which means that in these cases the effect of nonadjusted dominant gene interactions and epistazis is stronger than the additive effect. High values for heritability coefficient were recorded for the number of rows per ear, grain production, and the percentage of erect plants, which means that transmission of these characters to other genotypes can be done efficiently. The majority of characters are mainly dominated by dominant genes, with a dominance ratio greater than 1, except for the percentage of erect plants.

inbred lines, dialell system, heritability coefficient, combination capacity

field crops and pastures

Presentation: poster