Diversidade genetica do DNA mitocondrial em populações cultivadas e selvagens da Pirapitinga-do-Sul, Brycon opalinus (Cuvier, 1819) (Characiforme, Characidae, Bryconiae), na Bacia do Paraíba do Sul

AUTOR(ES)
DATA DE PUBLICAÇÃO

1999

RESUMO

.RFLP (Restriction Fragment Length Polymorphism) analysis of mitochondrial DNA was carried out to investigate the population genetic structure and its potential as a tool to identify and manage the cultured and wild populations of Pirapitinga-do-sul ? Brycon opalinus (Cuvier, 1819) (Characiforme, Characidae, Bryconiae) in the Paraíba do sul watershed. DNA samples from 283 fish, collected in 7 rivers of Paraíba watershed and in the Hydrobiology and Aquaculture Station of Paraibuna (CESP), were analysied. 24 restriction enzymes were screened and 6 (Apa I, Ava ll, EcoR I, Hinc ll, Hpa I, Nhe I) of them which produced multiple cutling sites in the molecule were selected. The combination of the 6 informative enzymes .revealed 27 haplotypes. The mtDNA of Pirapitinga-do-sul had 16.300 ( ± 500) bp long. No length heteroplasmy was found but restriction site heteroplasmy was observed in 17.5% of the fish from the Hydrobiology and Aquaculture Station of Paraibi.ma (CESP), as well as in 2.7% of the samples from Negro River, and 15.7% from Peixe River. Two haplotypes (25 and 26) were tound exclusively in the hatchery facilities. Such haplotypes can provide information on both the survival and long term reproductive success of stocked fish. Haplotype diversities were high both in the population from the Aquaculture Station (h=0.75), and from the wild (h=0.62). Nucleotide diversity among the 27 haplotypes found for the Brycon opalinus was 0.825%. The molecular variance analysis (AMOVA - nAnalysis of MOlecular V Ariancen) showed that the largest percentage of variance was observed within populations (70,02%). However, 15,97% of the total diversity were explained by interpopulation variance. Computer simulations of mt DNA variabilty indices were used to appraise the present situation of broodstock kept in captivity for stocking purposes. Also, genetic structure of natural populations, its evolution aspects and the relationship between conservation of riverine habitats and mitochondrial genetic variability of wild populations were discussed

ASSUNTO(S)

brycon peixe

ACESSO AO ARTIGO

Documentos Relacionados