Identification of inter-specific hybrid between Cajanus cajan (L.) and C. cajanifolius (H.) using cyto-morphological and DNA markers

Abstract

Cajanus cajanifolius, the putative progenitor of domesticated C. cajan, has many agro-economic traits those need to be introgressed into the cultivars of pigeonpea to widen its genetic base. In this study interspecific F1 hybrids, involving C. cajan (ICPL 87119) and C. cajanifolius (ICPW 31), were raised, and their response to bruchid infestation also assessed. Subsequently, the hybrids were characterized using the morphological, cytological and DNA markers based attributes. The F1 hybrids showed resistance to bruchid infestation caused by Callosbrochus maculatus and C. chinensis. The morphological traits of F1 hybrids with respect to their parents revealed that these were intermediate between the parents with predominance of the characteristics of both the parents. The pollen mother cells (PMC) obtained from the F1 hybrids showed regular meiosis involving 11 bivalents in majority of the cases which affirmed the genetic homology between these two species. But, heteromorphism was noticed for two bivalents during diakinesis. DNA marker (SCoT and SSR) analysis also revealed polymorphic fragments between the parents and their inheritance to the putative F1 hybrid. In conclusion, the simultaneous use of cyto-morphological analysis and DNA marker based genotyping demonstrated the genetic divergence between the parental genotypes with contrasting response to bruchid infestation and the hybridity of the F1 plants with accuracy.

Keywords

• dna marker
• bruchid resistance
• hybrid identification
• pigeonpea