Gene effects of Cicer reticulatum on qualitative and quantitative traits in the cultivated chickpea

The gene effects of Cicer reticulatum on both double-podding as qualitative traits and yield criteria as quantitative traits in interspecific hybridization with cultivated chickpea (Cicer arietinum) have not yet been elucidated, despite the easy acquisition of hybrid progeny between two species. This study sought to answer three questions concerning qualitative and quantitative traits in reciprocal crosses between C.arietinum and C.reticulatum. (i) Is there a similarity in the gene effects of flower colour, pigmentation and double-podded traits in reciprocal interspecific crosses? (ii) What are the expressivity and penetrance of the double-podded trait in interspecific crosses? (iii) Which heterosis predicts the occurrence and the extent of transgressive variation? The materials for this study were F-1, F-2 and F-3 progeny derived from a reciprocal cross between C.arietinum and C.reticulatum. As qualitative traits, purple flower colour, pigmentation and single-podded traits in C.reticulatum were governed by a dominant single gene. Purple flower colour and pigmentation were detected to be linked traits as all progeny had the same phenotypes. As quantitative traits, yield criteria in progeny which were double-podded had higher values than the single-podded counterparts. Expressivity and penetrance of the double-podding trait were superior in progeny derived from C.reticulatumxC.arietinum. The results showed that fruitful heterosis was more useful than residual heterosis in F-3 as residual heterosis was mostly negative and fruitful heterosis was suggested in self-pollinated species such as chickpea that lacks inbreeding depression. Interspecific transgression was significant with respect to chickpea improvement because it represented a potential source of novel genetic variation.