Myanmar mango landraces reveal genetic uniqueness over common cultivars from Florida, India, and Southeast Asia

Mango (Mangifera indica) is believed to have evolved in a large area spanning northeastern India, Bangladesh, and northwestern Myanmar. We compared the genetic structure of mango accessions from Myanmar with that of mango accessions from Florida, India, and Southeast Asia with 11 SSR markers. The Myanmar accessions exhibited considerable genetic diversity (unbiased heterozygosity, UHe = 0.698) and a high number of private alleles. Despite the low degree of genetic differentiation among accessions (global Fst, tetha = 0.123), Myanmar's accessions were distinguishable from mango accessions from Florida, India, and Southeast Asia in a principal coordinates plot. Genetic differentiation of the Myanmar accessions from other groups was also observed in a Bayesian cluster analysis. No population structure among Myanmar accessions was revealed by a neighbor-joining tree. Our results revealed a broad genetic background and genetic distinctiveness of mango in Myanmar. We discuss the implications for diversification mechanisms based on the embryo type characteristics and provide recommendations for conservation efforts.