Variabilidade genética em populações de tambaqui (Colossoma macropomum, Cuvier, 1816) com uso de marcadores ISSR

Abstract

The species Colossoma macropomum, popularly known as tambaqui, is a native fish of brazilian Neotropics that excels in national aquaculture as the native species most widely cultivated. However, in your natural environment, they were stocks will reduced, requiring the elabotion of management and conservation measures (including the closed season and restocking) to minimize the impacts left by human action. To manage the fishery tambaqui genetic resources in nature or captivity, must wear monitoring in populations, considering the dynamics of ecological aspects and the importance of your genetic variability. In spite of all aquaculture importance few has been studied with respect to variability reduction farmed stocks for this species, and about the variability in your natural environment. Currently different molecular markers are used for studies of genetic variability of the tambaqui, as well as to know the structure of the populations and their intra-and interpopulacionais relations. Thus the objective of assessing the genetic diversity in different captive populations and an thus the objective of assessing the genetic diversity in different captive populations and an wild population of tambaqui, through ISSR markers. Intrapopulacionais and interpopulacionais analyses were carried out to check the genetic populations diversity in the North and northeast of Brazil population of tambaqui, through ISSR markers. Intrapopulacionais and interpopulacionais analyses were carried out to check the genetic diversity of populations studied in the North and northeast of Brazil. DNA extraction was made by phenol-chloroform protocol. Twenty-nine ISSR molecular markers have been tested, being thirteen selected by presenting better degree of polymorphism and sharp picture of the patterns of bands. From the analysis of the loci read was the array of presence and absence, and with the use of statistical programmes were obtained the parameters of genetic diversity within and between populations, percentage of polymorphic bands Shannon index, Nei's genetic diversity, population differentiation and gene flow. Pondering the fixation index values, the results demonstrated a differentiation. The genetic variability in populations of fish farming was relatively low when compared to the wild population. With the findings of this work different management strategies may be suggested for the purpose of improvement of players cultivated and conservation of genetic heritage of these populations.