Cross-amplification of heterologous microsatellite markers in Piracanjuba/Amplificacao cruzada de marcadores microssatelites heterologos em piracanjuba

Brycon orbignyanus, popularly known in Brazil as piracanjuba, is a fish with great economic value but whose natural population drastically decreased in number during the last years. In this context, genetic variability studies of natural stocks and in restocking programs are fundamental for the adoption of conservation measures. Current analysis verifies the cross-amplification of heterologous primers in B. orbignyanus. Fifty-two primers of the species Brycon opalinus, Brycon hilarii, Brycon insignis, Prochilodus sp., Piaractus mesopotamicus, Colossoma macropomum and Oreochromis niloticus were tested. Primers with the best reproducibility were applied to a sample of 20 individuals and the genetic parameters were calculated. Nine primers provided good results for cross -amplification with B. orbignyanus, involving (BoM5 and BoM13) of Brycon opalinus, (Bh5, Bh6, Bh8, Bh13 and Bh16) of Brycon hilarii, (Bc48-10) of Brycon insignis and (Par80) of Prochilodus argenteus. Primers of Piaractus mesopotamicus, Colossoma macropomum and Oreochromis niloticus failed to provide amplification or provided non-specificity. Results demonstrated the possibility of using primers of different species and genera of B. orbignyanus, facilitating genetic studies on the species. Key words: Brycon orbignyanus, conservation, molecular markers, heterologous primers. A piracanjuba (Brycon orbignyanus) e um peixe de grande valor economico que nos ultimos anos tem apresentado uma reducao drastica em suas populacoes naturais. Nesse contexto, estudos de variabilidade genetica dos estoques naturais e nos programas de repovoamento sao fundamentais para adocao de medidas conservacionistas. O objetivo do presente trabalho foi verificar a amplificacao cruzada de primers heterologos em B. orbignyanus. Foram avaliados um total de 52 primers das especies Brycon opalinus, Brycon hilarii, Brycon insignis, Prochilodus sp., Piaractus mesopotamicus, Colossoma macropomum e Oreochromis niloticus. Os primers com melhor reprodutibilidade foram aplicados a uma amostra de 20 individuos e os parametros geneticos foram calculados. Nove primers apresentaram resultados satisfatorios de amplificacao cruzada com B. orbignyanus, sendo das especies Brycon opalinus (BoM5 e BoM13), Brycon hilarii (Bh5, Bh6, Bh8, Bh13 e Bh16), Brycon insignis (Bc48-10) e Prochilodus argenteus (Par80). Os primers de Piaractus mesopotamicus, Colossoma macropomum e Oreochromis niloticus nao apresentaram amplificacao ou apresentaram inespec