Unravelling genetic make-up of some Musa hybrids and selected Musa accessions using molecular and morphological characterization

Abstract

Plantains are important staples in sub-Saharan Africa, however, production has been saddled by several constraints including pests and diseases and lack of improved technologies. In regard to genetic study, morphological characterization has identified about 100 local accessions to exist in Ghana. However, limited molecular characterization has been done on plantains. Characterization based on morphologic characteristics alone may be limited since expression of quantitative traits is subjective to strong environmental influence. Alternatively, molecular characterization techniques are capable of identifying polymorphism represented by differences in DNA sequences. The objective of this research was therefore to characterize local accessions of plantain using morphological and molecular techniques. This study sampled 38 local accessions from two regions in Ghana for characterization, taking into account all known morphological characteristics. Genomic DNA was isolated for molecular characterization using 18 SSR markers and 10 random primers. The SSR markers revealed 52 alleles, random primers revealed 67 alleles and the 29 morphological traits (loci) had 79 attributes (alleles). Similarity matrices of SSR markers revealed that 26.5% of the plantain accessions were duplicates; however, random amplified polymorphic DNA (RAPDs) system and morphological marker systems did not reveal any duplication among genotypes. Dendrogram generated on bases of both SSR and RAPDs indicated that a French plantain accession (Apem 01) and a False Horn accession (Apantu 26) were the most distantly related collections. None of the molecular marker methods used clearly clustered various phenotypically known collections into their respective distinct groups, although to some extent, this was demonstrated by morphological data set. Key words: Dendrogram, genome, morphological, molecular, random amplified polymorphic DNA (RAPDs), simple sequence repeats (SSR).