Abstract

Saad Ebeid, Hussein Zaghloul and Atef Pasha Sirri

Five Egyptian parental genotypes of Faba bean were used for carrying out half diallel design to study heterosis and nature of gene action for earliness, vegetative, yield and yield components traits. Mean squares of genotypes were found to be highly significant for all studied traits. The results showed that the majority of crosses exhibited significant heterosis estimates for better parent for all studied traits. General combining ability (GCA) and specific combining ability (SCA) mean squares were highly significant for all studied traits. The results indicated that the magnitude of additive genetic variance (σ 2 A) were positive and lower than those of non additive (σ 2 D) one for all the studied traits, indicating that non additive gene action played a major role in the inheritance of different traits under study. The broad sense heritability estimates (H2 b %) were more than their corresponding narrow sense heritability (H2 n %) for all studied traits. However, estimates of narrow sense heritability were 34.2 and 14.8% for earliness traits and ranged from 15.2 to 29.8% for number of branches per plant and plant height, respectively. Respecting to yield components, the estimates of narrow sense heritability ranged from 8.8 to 70.9% for number of pod per plant and weight of 100 seed (g), respectively. The results showed that the two cultivar, Giza 843 (P4) and Misr 2 (P1) was good general combiner for earliness, yield and yield components, respectively. The cross (P1xP5) showed desirable SCA effects and significant heterosis values for earliness, and yield components. While, the two crosses, (P1xP3) and (P3xP4) exhibited desirable SCA effects for vegetative traits. These promising crosses could be used for breeding programs to produce pure lines.