Genetic polymorphism, molecular characterization and relatedness of Macrobrachium species (Palaemonidae) based on RAPD-PCR

Abstract

ABSTRACT. The prawn genus Macrobrachium belongs to the family Palaemonidae. Its species are widely distributed in lakes, reservoirs, floodplains, and rivers in tropical and subtropical regions of South America. Globally, the genus Macrobrachium includes nearly 210 known species, many of which have economic and ecological importance. We analyzed three species of this genus (M. jelskii, M. amazonicum and M. brasiliense) using RAPD-PCR to assess their genetic variability, genetic structure and the phylogenetic relationship between them and to look for molecular markers that enable separation of M. jelskii and M. amazonicum, which are closely related syntopic species. Ten different random decamer primers were used for DNA amplification, yielding 182 fragments. Three of these fragments were monomorphic and exclusive to M. amazonicum or M. jelskii and can be used as specific molecular markers to identify and separate these two species. Similarity indices and a phylogenetic tree showed that M. amazonicum and M. jelskii are closest to each other, while M. brasiliense was the most differentiated species among them; this may be attributed to the different habitat conditions to which these species have been submitted. This information will be useful for further studies on these important crustacean species.

Genetic variability and phylogenetic aspects in species of the genus Macrobrachium

“…This problem is more evident between Macrobrachium amazonicum and Macrobrachium jelskii, which are closely related and syntopic species. Furthermore, the high genetic similarity between them is consistent with the probable conditions of metapopulations or interspecific hybrids (Guerra et al, 2010).…”

“…On the other hand, the high level of intrapopulation divergence in Mj from Mendonça can be attributed to human interference, which modified the population's genetic structure. The dam from Mendonça is constantly under human interference, mainly concerning the release of specimens that are used as live bait in the sport fishing (Magalhães et al, 2005;Guerra et al, 2010).…”

“…Particularly, in the Upper Paraná and Tiete River, the occurrence of these species has been associated with ecological and conservation genetic studies; because they are exotic species, they were probably introduced as a result of human-mediated dispersion, either accidentally or for aquaculture (Magalhães et al, 2005;Guerra et al, 2010;Vergamine et al, 2011). However, besides their economic and ecological factors, Brazilian Macrobrachium species have been poorly studied, and genetic studies are important to reinforce these aspects.…”

“…According to several authors, these processes are very difficult and questionable because the prawns seem to have high morphological conservation (Zhang et al, 2009;Guerra et al, 2010). This problem is more evident between Macrobrachium amazonicum and Macrobrachium jelskii, which are closely related and syntopic species.…”

Genetic relationships of Pacific abalone (Haliotidae) species determined using universal rice primer-polymerase chain reaction fingerprinting

“…The RAPD assay has been used to construct phylogenetic trees for resolving taxonomic problems in many organisms (Guerra et al, 2010;Abdul Muneer et al, 2011;Apostolidis et al, 2011). The major limitation of the RAPD technique is repeatability.…”