Investigating inheritance patterns of a spontaneous mutant in pigeonpea and its future implications for CGMS based hybrid breeding 

Despite concerted breeding efforts directed towards genetic improvement of pigeonpea, huge gap exists between its potential and actual yields. Recently, in order to stabilize pigeonpea yield the CGMS- based system has been established in pigeonpea. Maintenance of the genetic purity of parental lines and hybrids, however, remains one the greatest challenges associated with CGMS-based system. In the context, identification of some markers clearly discriminating the parental lines and hybrids would be of immense importance. With this view, here we report the discovery of a spontaneous mutant phenotype that would act as potential visual marker in the CGMS based hybrid breeding programmes. Moreover, the nature of inheritance for the mutant phenotype was also examined. All the F1s derived from a bi-parental cross (mutant × normal) were normal with lanceolate leaves and normal flower morphology while the F2 and backcross generations segregated in ratio of 3:1 and 1:1, respectively indicating monogenic recessive inheritance of the gene(s) under investigation. More importantly, existence of a single gene affecting both traits would facilitate rapid introgression of these morphological markers into genetic backgrounds of different A-lines which will help in differentiating the CGMS-hybrids from their parental lines (A-lines). It is envisaged that these morphological markers would greatly assist pigeonpea breeders in maintaining the genetic purity while dealing with CGMS system in pigeonpea.