Genetic diversity of wild Musa acuminata in Sumatra

Abstract The islands of Indonesia are a major part of the centre of origin of bananas. Here, we evaluated the diversity at 164 locations of Sumatra and added 20 wild banana accessions originating from other islands of Indonesia. We analysed morphological characteristics in a principal components analysis (PCA) and genotyped accessions at four nuclear gene regions, i.e. ADH3, CAT2, GBSS1 and IDH1. By combining the geographical coordinates with the morphological variation, we developed a spatial multivariate analysis. The PCA of the morphological traits clearly separated three major clusters. Based on the collected information, we propose to merge the previously described var. halabanensis and var. alasensis Nasution into the subsp. halabanesis . Moreover, we argue that the var. sumatrana should be considered as a subspecies taking into account its genetic and morphological unique characters in addition to its geographical distribution. The four nuclear genes genotyping showed a high genetic diversity of M. acuminata often in admixed stands of different haplotypes. Based on the allele frequencies, there was a significant deviation from a Hardy–Weinberg equilibrium with a high level of homozygosity. Multi-locus genetic population structure analysis confirmed the existence of three major clusters with further possible subdivisions. The discovered genetic diversity in the wild M. acuminata population across Sumatra expands the current knowledge and awaits its deployment in ongoing breeding efforts for this important crop.