Diversity and differentiation of mango populations from eastern Kenya

M.E.M. Toili, F.K. Rimberia, A.B. Nyende, D. Sila
This study aimed to characterize mango accessions and study genetic differentiation among subpopulations from eastern Kenya. Twenty International Plant Genetic Resources Institute (IPGRI) mango descriptors were selected for visual assessment of 91 accessions, both indigenous and exotic. Simple sequence repeat (SSR) markers were employed in the molecular analysis. Morphological data were subjected to multivariate analysis, ANOVA and chi-squared test. Informative statistics for the markers were generated using GenAlEx software and a phylogenetic tree was reconstructed. An FST matrix was generated and analysis of molecular variance (AMOVA) was conducted. Selected descriptors were polymorphic for phenotypic characters of the accessions. The first seven principal components accounted for 79.1% of the variation, with leaf and fruit traits being most significant. Varietal clustering was observed on the phylogenetic tree, with indigenous varieties clustering separately from exotic. Twenty-five alleles were detected in the population; however, low genetic differentiation was observed among subpopulations, with a mean FST of 0.037. AMOVA revealed that molecular diversity was highest within individuals. These results will be a useful resource in further exploitation and improvement of mango.
Toili, M.E.M., Rimberia, F.K., Nyende, A.B. and Sila, D. (2017). Diversity and differentiation of mango populations from eastern Kenya. Acta Hortic. 1183, 73-82
DOI: 10.17660/ActaHortic.2017.1183.11
Mangifera indica, morphological diversity, molecular diversity, genetic differentiation

Acta Horticulturae