Genetic monitoring by rapd markers for repopulation programs of Salminus brasiliensis (Pisces, Characiformes)

Abstract

The preservation of the genetic variability of hatchery stocks used to supplement natural populations is a priority. Current study employed RAPD markers to examine the genetic diversity of dourado samples from the middle Paranapanema river and from the broodstock used in the stock enhancement program of the Aquaculture and Hydrobiology Station at the Salto Grande Hydroelectric Power Plant. Nineteen RAPD primers were analyzed, which generated 299 bands and the latter were used for genetic analysis. The percentage of polymorphic fragments was higher in stock captured in the Paranapanema river than from fry stocks. The genetic diversity was lower in the broodstock than in natural population. Amova results showed that most interpopulation genetic variation lay within stocks (83.9%) and not between them (16.1%). Moderate genetic differentiation (F ST = 0.16) was reported. Nevertheless, differentiation decreased when the four fry stocks were mixed and analyzed as a single population (F ST = 0.07). Instead of releasing each lot separately into the water, mixing specimens produced in the various fry stocks before releasing them in the river would be more feasible. The restocked population will have a genetic structure closer to natural populations.

Genetic Variability of Brycon hilarii in a Repopulation Program

“…Genetic interaction among the fish released and wild populations may cause loss of alleles, especially those related to adaptation ). Molecular markers, especially microsatellites, have been widely used for information on the genetic variability of broodstocks and wild populations (Povh et al 2011;Almeida et al 2013;LoperaBarrero et al 2015). Microsatellites warrant a more specific analysis in population structures since they have high genetic mutation rates when compared to other DNA parts.…”

Genetic diversity of Salminus brasiliensis wild populations in downstream and upstream Cachoeira Branca, Verde River MS Brazil: a preliminary view

“…Dominant marker in current assay proved efficient in the study of genetic variability. Other studies with the same marker for S. brasiliensis (ALMEIDA et al, 2013;GOMES et al, 2011GOMES et al, , 2013LOPES et al, 2007) and in other fish species (JACOMETO et al, 2010;, 2010LOPES et al, 2009;PAULA et al, 2006;POVH et al, 2008b) also gave positive results. In fact, dominant markers still have great possibilities of information for the initial review of genetic processes in natural populations or in fish stocks.…”

Genetic variability of wild populations of Leporinus elongatus in the São Domingos River - MS Brazil: a preliminary view on the construction of the hydroelectric plant

“…Current analysis showed that dominant markers may be a simple tool to achieve these aims. According to Hilsdorf (2013), the employment of dominant markers to estimate variability is common in fresh water fish and is corroborated by several recent research works in Brazilian native species (ALMEIDA et al, 2013;GOMES et al, 2011GOMES et al, , 2013JACOMETO et al, 2010;LOPERA-BARRERO et al, 2010;RAMOS et al, 2012).…”

“…Above results coupled to exclusive and fixed fragments demonstrated that even populations with low-frequency fragments have a high intrapopulation genetic variability plus a trend for genetic differentiation. Shannon´s Index and the percentage of polymorphic fragments are genetic parameters successfully employed to estimate the genetic variability of the population (ALMEIDA et al, 2013;GOMES et al, 2011GOMES et al, , 2013JACOMETO et al, 2010;LOPERA-BARRERO et al, 2010;PAULA, 2006). The analysis of molecular variance (AMOVA) between the populations revealed a greater intra-population rather than an inter-population variation.…”

“…Further, other recent research works demonstrated the efficiency of these techniques in restocking programs or in broodstocks of other native species (ALMEIDA et al, 2013;GOMES et al, 2011GOMES et al, , 2013JACOMETO et al, 2010;LOPERA-BARRERO et al, 2010). Due to easy techniques and extensive polymorphism, markers are highly common in research on neotropical fish (HILSDORF, 2013).…”