Gene introgression in grain legumes uri icon

abstract

  • The wild species of grain legumes are valuable gene pools, particularly for resistance to biotic andabiotic stresses. These have largely remained under-utilized due to crossability barriers, but there are someexamples of successful introgression of genes into the cultivated species from their wild relatives, particularlythose constituting primary and secondary gene pools. In chickpea, two closely related species, Cicerreticulatum and C. echinospermum, have been used for widening genetic base of the cultigen and introgressinggenes for resistance/tolerance to phytophthora root rot, cyst nematode (Heterodera ciceri), root-lesionnematode (Pratylenchus spp.), pod borer (Helicoverpa armigera), ascochyta blight, botrytis grey mould andlow temperatures. Wild Cajanus species have been effectively exploited in developing cytoplasmic malesterility (CMS) systems, which made commercial hybrids possible. In addition, resistance to Helicoverpaarmigera and sterility mosaic has been introgressed from C. acutifolius and C. scarabaeoides. The highprotein content trait has been introgressed from C. scarabaeoides. In Phaseolus beans, the cultivated speciesof the secondary (P. coccineus and P. dumosus) and the tertiary (P. acutifolius) gene pools have been usedfor the improvement of common bean (P. vulgaris). The congruity back cross system and its modificationshave been especially useful for tapping the tertiary gene pool. In lentil, genes for anthracnose and wiltresistance and drought tolerance have been introgressed in the cultigen from L. lamottei. Presence ofcrossability barriers has restricted greater exploitation of wild species, particularly in tertiary gene poolConcerted efforts are needed to overcome these crossability barriers. Cloning of desired genes from crossincompatiblewild species and their transfer through transgenic approaches may also be considered

publication date

  • 2009