ESTIMATIOIN OF COMBINING ABILITY AND GENETIC VARIANVE IN MAIZE

Abstract

A factorial mating analysis between four males inbred lines of maize (Agr183, W13R, W17.161 and R153) and six females lines (OH40, IK58, IK8, ZP, DK and SH) were studied using a randomized complete block design with three replications. Data were collected for yield, its components, protein and oil percent. The analysis carried out according to the factorial mating design method of to study the combining ability and gene action. The results showed highly significant differences among genotypes for all studied characters.The line SH appear to have good general combining ability for larger number of characters followed by IK8 and ZP. The crosses showed differences in its specific combining ability effects. The crosses (ZP x W13R) and (OH40 x W17.161) have specific combining ability effects in desirable direction for most characters. The dominance genetic variance was more important than the additive variance for the most studied characters, and the estimates of average degree of dominance was greater than one for all characters. Broad sense heritability ranged from 86.77% for ear diameter to 99.62% for 100 grain weight, while narrow sense heritability ranged from 20.92% for protein percent to 61.40% for number of rows per ear.