Genetic diversity in natural populations of Jacaranda decurrens Cham. determined using RAPD and AFLP markers

Bianca W Bertoni,Mirian V Lourenço,Suzelei De C França,José O Pereira,Milena G Malosso,Mariana P De C Telles,Simone C.Z Torres,Ana M.S Pereira

doi:10.1590/s1415-47572010005000068

Abstract

Jacaranda decurrens (Bignoniaceae) is an endemic species of the Cerrado with validated antitumoral activity. The genetic diversity of six populations of J. decurrens located in the State of São Paulo was determined in this study by using molecular markers for randomly amplified polymorphic DNA (RAPD) and amplified fragment length polymorphism (AFLP). Following optimization of the amplification reaction, 10 selected primers generated 78 reproducible RAPD fragments that were mostly (69.2%) polymorphic. Two hundred and five reproducible AFLP fragments were generated by using four selected primer combinations; 46.3% of these fragments were polymorphic, indicating a considerable level of genetic diversity. Analysis of molecular variance (AMOVA) using these two groups of markers indicated that variability was strongly structured amongst populations. The unweighted pair group method with arithmatic mean (UPGMA) and Pearson's correlation coefficient (RAPD -0.16, p = 0.2082; AFLP 0.37, p = 0.1006) between genetic matrices and geographic distances suggested that the population structure followed an island model in which a single population of infinite size gave rise to the current populations of J. decurrens, independently of their spatial position. The results of this study indicate that RAPD and AFLP markers were similarly efficient in measuring the genetic variability amongst natural populations of J. decurrens. These data may be useful for developing strategies for the preservation of this medicinal species in the Cerrado.

Highlights

The study of population and genetic diversity is a complex subject that involves the analysis of DNA sequences, gene adaptability, inter-individual variation and speciation, and an understanding of the interactions among organisms that compose communities
Mogi Guaçú São Carlos Pratânea Itatinga Patrocínio Paulista Altinópolis Total. This is the first study to use random amplification of polymorphic DNA (RAPD) and amplified fragment length polymorphism (AFLP) molecular markers to examine the genetic variability of natural populations of J. decurrens in the State of São Paulo
The high variability reported here indicates that these markers are useful for analyzing the genetic constitution of the six populations that were studied; this conclusion was supported by the number of polymorphic bands observed (Tables 2 and 3), by the allele frequencies (Table 4) and by Analysis of molecular variance (AMOVA) (Table 5)

Summary

Introduction

The study of population and genetic diversity is a complex subject that involves the analysis of DNA sequences, gene adaptability, inter-individual variation and speciation, and an understanding of the interactions among organisms that compose communities. Molecular markers provide an important tool for assessing the genetic variability and structure of natural populations, and for studying biodiversity in general (Frankham et al, 2002). They provide a basis for developing programs to protect flora threatened with extinction. Polymorphisms detected by AFLP generally indicate Mendelian inheritance and may be used to study kinship and genetic variability within and between populations. AFLP is a robust tool for DNA fingerprinting of genomes (Vos et al, 1995)

Methods

Results

Conclusion