GENETIC CHARACTERIZATION OF REMAINING POPULATIONS OF Paratecoma peroba, AN ENDANGERED AND ENDEMIC SPECIES OF THE ATLANTIC FOREST

Abstract

Background: The objective of this study was the genetic characterization of remaining populations of
the species Paratecoma peroba occurring in fragments of the Atlantic Forest, by estimating parameters
of diversity and genetic structure. The study was carried out in two forest fragments, the Atlantic Forest
Environmental Education Pole (area 1) and the Pacotuba National Forest (area 2), where 93 adult trees
were identified.
Results: Ten Inter Simple Sequence Repeats (ISSR) primers were used in genotyping, obtaining 112
amplified bands with 87.5% polymorphism. The genetic diversity estimated for the populations from the
Nei (H*) and Shannon (I*) indices was higher for area 1. For the joint data, moderate genetic diversity
was observed, referring to the average values of 0.26 and 0.40, obtained for the H* and I* indices,
respectively. Molecular variance analysis resulted in moderate differentiation between populations (ΦST
= 0.143), while gene flow analysis (N m = 6.69) revealed the occurrence of similar alleles between them.
However, the predominance of a single genetic group in area 2, revealed from Bayesian approach,
indicates that its genetic structure, possibly generated by the current scenario of fragmentation of the
Atlantic Forest and the distancing of populations, affecting the contemporary gene flow.
Conclusion: Despite the moderate genetic diversity of the species for the area 2 population, actions
toward inclusion of seedlings obtained from seeds from neighboring fragments, including area 1, and the
increase in the connectivity of forest fragments through ecological corridors, could assist in augmenting
its genetic variation.