Abstract

Knowledge of the genetic variability of plantain cultivars in the Democratic Republic of the Congo (DRC) is limited. This study assessed genetic diversity and relationships in three plantain accessions differing in pseudostem color at seven microsatellite loci using SSR markers. DNA was extracted from banana leaves, and PCR was performed with unlabeled and fluorescent-labeled SSR primers and eventual capillary sequencing. Different population genetic analysis software was used to interpret the fragment analysis data. There was a high allelic power with a mean polymorphic information content of 0.83. A high average genetic diversity was indicated by Nei's Gene Diversity Index (h: 1.38) and the Shannon Information Index (I: 2.22). Pairwise genetic similarity between plantain genotypes averaged 0.82. A dendrogram grouped the 60 genotypes into three clusters. AMOVA showed high genetic variation within the population (98%) compared to the variation between populations, with no significant difference between the three cultivars regarding the color of the pseudostem. In contrast, these cultivars were closely related to each other. No correlation between the morphological and molecular characterization of cultivars was observed. We recommend a follow-up study with other plantain cultivars from other regions and large sample size for more representative data.

Key words: Characterization, microsatellites, genetic diversity, plantain cultivars.