Molecular diversity and phylogenetic relationship of native Garcinia (mangosteen and relatives) from Kalimantan, Indonesia

Abstract

Importance of the work: Globally, Indonesia is one of the biggest producers of
mangosteen (Garcinia mangostana L.), known as the “queen of fruits”.
Objectives: To determine the molecular diversity and phylogenetic relationship of
mangosteen and its wild relatives (Garcinia spp.), native to Kalimantan, Indonesia, using
the matK and rbcL markers and to compare these to other data in the GenBank database.
Materials and Methods: In total, 34 Garcinia samples were used, with 12 originating
from Kalimantan, Indonesia. Molecular analysis began with DNA isolation using a CTAB
method, with a soft modification. Next, the DNA isolates were quantified and amplified
using an ultraviolet-visible spectrum spectrophotometer and a thermal cycler to perform
polymerase chain reaction. The DNA targets (matK and rbcL) were sequenced using the
ABI PRISM 377 sequencer at Apical Scientific Sdn. Bhd. (Seri Kembangan, Selangor,
Malaysia). The molecular diversity was assessed using the nucleotide diversity index (π),
while the molecular phylogeny was determined based on maximum likelihood analysis
with a statistical bootstrap.
Results: Molecular analysis revealed that Garcinia had high molecular diversity,
as indicated by π values of 0.062 for matK and 0.083 for rbcL. The phylogenetic analysis,
based on the combination of the matK and rbcL markers, revealed that this germplasm
could be divided into three (local scale) and six groups (global scale), with G. mangostana
being closely related to G. parvifolia, G. latissima, and G. dulcis.
Main finding: This essential information could be used to enhance the future efficiency
and effectiveness of the mangosteen breeding and conservation program.