Inheritance of seed size in chickpea

Six lines of chickpeas (Cicer arietinum) with a range of seed size from 10.42 to 58.42 g per 100 seeds were used in a complete diallel cross to study the inheritance of seed size. Parent lines, 15 F1s, 15 F2s, 15 BC2s were grown at Tel Hadya, Syria, during 1988-89. Combining ability and generation mean analyses showed that both additive and non-additive gene effects were important with the preponderance of additive gene action for seed size. Combining ability, graphical and generation means analyses revealed the partial dominance of small over large seed size suggesting that seed size is governed by recessive genes. Therefore, it is suggested that a backcross with a large-seeded parent may enhance the chances of large-seeded segregants. Generation mean analysis helped in detection of epistasis in 11 out of 15 crosses. Among epistatic effects, additive × additive effects, were noticed in 6 crosses, additive × dominance effects in 4 crosses, and dominance × dominance effects in 6 crosses. The narrow-sense heritability of seed size was > 95%. As dominance and genic interactions also played a significant role, it is suggested to delay the selection of large seed size to F3 generations onward so that these effects are reduced. Bulk-pedigree method is suggested for the improvement of seed size in chickpea