Heterotic Effect, Combining Ability and Significance of Synthetics over Line Cultivars in Faba Bean (<i>Vicia faba</i> L.) Grown under Semi-Arid Zones

Abstract

The aim of this study was to investigate the amount of heterosis and performance of faba bean synthetic cultivars compared to line cultivars under semi-arid conditions. Five inbred lines in at least S 6 generation were developed and used to develop <i> F </i> 1 s hybrid (in all possible combination excluding reciprocal), lines mixtures (Syn-0) and synthetic generations of Syn-1. Evaluation of the entries showed the lines to have high general and specific combining ability, high yield and high average degree of cross-fertilization (0.36); hetrosis relative to mid-parent for yield was 67%. Lines mixture from four inbred lines (Hudeiba/93, Bassabier, Ed-Damar and Shabah) gave the highest yield of 3.40 t/ha for Syn-0 and 3.96 t/ha for Syn-1. Compared to the average yield t/ha of the pure stand of the four lines (3.11 t/ha), the increase in yield of was 9% in sy-0 and 27% in Syn-1. Compared to the individual yield t/ha of the pure stand of the lines, the performance of Syn-0 surpassed that of the indi vidual pure stands of the linesby 14% for Hudiaba/93 and Bassabier and 4% for Ed-Damar and 7% for Shabah, whereas the increase in performance of Syn-1 compared to pure stand of the lines was 32%, 25% and 21 % , respectively. The results confirm the previous knowledge on yield increase with successive syn-generations in faba bean due to the effects of heterogeneity and heterozygosity. Such results could be used as a base for an effective breeding program for improvement of yield of faba bean grown under the semi-arid zone s .