Cicer

Abstract

The cultivated chickpea (Cicer arietinum L.) produces hybrids with only two annual wild species, C. reticulatum and C. echinospermum. Cicer reticulatum is considered to be progenitor of cultivated chickpea. Both C. reticulatum and C. echinospermum, which are cross-compatible with the cultigen, are placed in the secondary gene pool. The remaining six annual wild Cicer species and the 34 perennial Cicer species do not naturally cross with the cultivated species and therefore are grouped into the tertiary gene pool. The genus Cicer has not been extensively investigated for crossability, taxonomy, cytology, genetics, breeding, and molecular biology. Although techniques are available to cross incompatible annual species from the tertiary gene pool with the cultivated species, hybrids are not available for the improvement of chickpea. Lack of crossability information on perennial species, which have several important genes, indicates that the enormous genetic potential of these species remains unexplored. Experimental evidence indicates that the barriers to hybridization between the primary gene pool and perennial Cicer species are post-zygotic and due to embryo abortion. Application of growth regulators delays embryo abortion up to 15–17 days but not to the stage of mature seeds. Considering the enormous potential of wild species in chickpea crop improvement, emphasis should be given to overcome barriers to hybridization with the cultivated species. Research on the presence of flavonoids in wild Cicer species conferring disease and pest resistance should be strengthened. Emphasis should also be given to the development of a robust molecular marker system for diversity analysis and eventual widespread use in marker-assisted introgression of genes from the wild Cicer species to cultivated forms.