Diallel Analysis of Yield and its Components in Grain Sorghum

The nature of combining ability in sorghum was studied in a set of diallel crosses of ten varieties from different ecogeographical regions. Variances for g.c.a., s.c.a. and reciprocal effect were significant and therefore need to be taken into consideration while choosing parents for breeding. The higher magnitude of g.c.a. than s.c.a. variances indicate that inheritance of these characters is predominantly governed by additive and additive × additive epistatic components of genetic variance. The strains, I.S. 200, Spur Feterita, Hegari derivative and Bichpuri are good general combiners The superior combinations involved all the three possible combinations between parents of high and low general combining ability effects i.e. High × High; High × Low and Low × Low. In general the superior combinations involved at least one high general combining parent Significant variance for reciprocal effects indicates the presence of maternal effect. It was significant for grain yield and number of seeds per panicle.