Isozyme-based genetic similarity in Cenchrus (Poaceae).

摘要

The genus Cenchrus is distributed throughout the tropics. Species relationships among the eight species of Cenchrus and some natural hybrids were studied using six isoenzyme systems that revealed C. ciliaris and C. setigerus as closely related. Cenchrus hybrids were intermediary to the C. ciliaris-C. setigerus group and the other group comprised of the rest of the species. Two clear groups of C. ciliaris and C. setigerus in one and the rest of the species in another group were observed. However, C. prieurii, which is exclusively sexually reproducing, formed a separate group most distant to C. ciliaris and C. setigerus. This study confirmed the taxonomic similarities based on morphological traits. Further, interspecific and intraspecific diversity analysis revealed a total of 74 electrophoretic phenotypes. Esterase isoenzyme exhibited maximum polymorphism with 20 electrophoretic phenotypes among these species.