The Annual Species of the Cicer Genus

Abstract

The genus Cicer contains both perennial and annual species, the latter being fewer in number. These are the domesticated chickpea C. arietinum ssp. arietinum and its wild progenitor ssp. reticulatum, C. echinospermum, C. pinnatifidum, C. judaicum, C. bijugum, C. yamashitae, C. cunneatum, and C. chorassanicum. These species form three crossability groups. Members of the same group are cross-compatible with one another, albeit with some difficulty in certain cross combinations. The resultant hybrids may be fertile, partially fertile, or sterile. The first group comprises the two subspecies of C. arietinum (ssp. arietinum and ssp. reticulatum) and C. echinospermum. The second group comprises C. pinnatifidum, C. judaicum, C, bijugum, C. yamashitae, and C. cunneatum. The first three species of this group are easily crossed with each other but the hybrids are self-sterile owing to excessive growth of the stigma outside the keel before anthesis. However, the seed set of these hybrids is nearly normal after hand pollination. The third group contains a single species, C. chorassanicum. The effective wild gene pool of domesticated chickpea consists of members of the first crossability group and particularly ssp. reticulatum. More collections of this taxon are needed because the available accessions are derived from only 18 original samples. Chickpea cultivation and domestication underwent two critical stages. The first was the selection of a germination-free type that enabled reasonable yields to be produced. As in the case of other domesticated legumes, such selection had apparently already occurred in wild stands. The second stage was the removal of the wild progenitor’s vernalization requirements, allowing chickpea to grow on residual moisture as a spring crop, thereby escaping the ascochyta disease that is usually destructive after autumn sowing.