The centre of origin and domestication of Ensete ventricosum (Welw.) Cheesman and its phylogenetic relationship to some Musa species

Abstract

Ensete ventricosum is one of the species in the genus Ensete whose species composition is not yet known. This paper attempts to trace the origin of domesticated enset and early food production in Ethiopia, historical evidence of its distributions, botanical and genetic diversity of cultivated and wild enset forms. Based on ecological distribution of wild enset in Ethiopia, the highly dissected terrain of lower altitudes of South and Southwestern drier zones might be the initial sites of enset domestication. The complexity of enset culture and its use value and in South and Southwest of Ethiopia indicate longer period of enset cultivation. The existence of an early and dynamic root and tuber crop-based agriculture before seed and fruit-based crop system also support the early domestication of enset in South and South West of Ethiopia. A molecular genetic data from RAPD, chloroplast and ITS DNA sequence suggest that different clones of cultivated enset seem to have originated from different clones of wild enset suggesting the existence of several microcentres of domestication in the region. The wild enset forms and the cultivated forms seem to introgress and escape to the wild and domesticated sites of enset, respectively. RAPD and ITS molecular data as well as complete sequences of transcribed spacers and introns from trnT terF region of chloroplast DNA from thirteen species of Musa and three species of Ensete, including the cultivated and wild species of Ensete ventricosum indicated that Ensete glaucum and Mussa beccarii represent ancestral forms of Ensete and Musa, respectively. The data also showed that E. ventricosum cannot be reduced to E. glaucum, nor can E. gilletti be reduced to E. ventricosum, as some authorities have suggested. Ensete gilletti or a species very close to it appears to be the ancestral species of E. ventricosum.

Keywords/phrases: Centre of origin and domestication, Ensete ventricosum, Molecular data, Musa species