Chapter 2 - Origin, distribution, and gene pools

Abstract

Chickpea (Cicer arietinum L.) is one of the oldest grain legume species. It is a rich source of protein (20%–23%), minerals, fiber, unsaturated fatty acid, and β-carotene. It is considered as one of the most nutritious food for human consumption. The crop has been domesticated in Fertile Crescent as part of agricultural evolution and considered as the primary center of diversity. Secondary centers of diversity emerged with the geographic spread across Mediterranean Europe, the Indian subcontinent, and Northeast Africa, and more recently in Mexico and Chile. The genus Cicer is blessed with rich germplasm which includes 44 species (43 wild relatives and 1 domesticated). These genetic resources are classified into three gene pools, i.e., primary, secondary, and tertiary, based on their usefulness for improving the cultigen. The primary gene pool consists of cultivated species and landraces. The secondary gene pool consists of the progenitor species C. reticulatum and C. echinospermum, the species that are crossable with C. arietinum, but with reduced fertility of the resulting hybrids and progenies. The tertiary gene pool consists of all the annual and perennial Cicer species that are not crossable with cultivated species. No perennial Cicer species are known to cross readily with the cultivated species and produce mature seeds. Based on crossability and fertility of hybrids in interspecific crosses, annual members of Cicer have been classified into four crossability groups.