The genetic diversity and population structure of Genipa americana L. in Northern Mato Grosso, Brazil

Abstract

Genipa americana L. (Rubiaceae) is an Amazon region-natural species, which may be subject to inbreeding, since it grows in fragmented environments. The aim of the current study is to assess the genetic diversity and population structure of three G. americana populations naturally grown in Northern Mato Grosso State using SSR markers. The DNA extraction was performed according to the CTAB method, with modifications. Six (6) SSR primers developed for the species were used. The allele frequency, the observed and expected heterozygosity, PIC (Polymorphism information content), and the Fixation Index were estimated. Molecular variance (AMOVA) and principal coordinates (PCoA) analyses were conducted, and the most likely number of groups (k) was inferred using the Structure software in order to help understanding the genetic structure of the populations. The three populations showed genetic diversity, shared genetic material and presented high inbreeding index due to low heterozygosity. The cluster analysis results showed genetic material sharing between populations, as well as lack of genetic structuring among individuals due to their geographical origins. As G. americana is a culturally and economically important native species, in addition to being attractive to wild animals, it is worth preserving forest fragments showing the occurrence of G. americana individuals to assure genetic