Crossability studies in Cajanus cajan (L) Millsp.

Wide hybridization has the scope to widen genetic and cytoplasmic basis of any crop species . In the present study, interspecific hybridization between two cultivars of pigeon pea and 3 wild species viz., C.platycarpus, C.volubilis and C.lineatus were attempted. The study aimed at developing methods to obtain interspecific hybrids by utilizing vast wild relatives of pigeonpea. First crossability of pigeonpea with its wild relatives was determined based on pollen germination and pollen tube growth. Among the 11 crosses, only Pusa-33 x C.lineatus showed post-zygotic barrier and in the other crosses it was pre-zygotic. Two out of seven treatments, use of organic solvent (n-hexane) and immunosuppressant (e-amino caproic acid) were effective in ensuring fertilization. But early pod abscission in these cases indicated the presence of post-zygotic barrier as well. Thus, combinations of methods are necessary to overcome the barriers to cross-ability. In vitro pollen germination medium was standardized for C.platycarpus. For the first time complete pollen germination media for pigeon-pea and a wild species C.volubilis have been standardized