GENETIC VARIATION OF Tor tambroides (Bleeker, 1854) ALONG BATANG TARUSAN RIVER, WEST SUMATERA: IMPLICATIONS FOR STOCK IDENTIFICATION

Abstract

Mahseer (Tor tambroides, Bleeker, 1854) is an important consumption fish species in the Batang Tarusan River, located in the West Sumatera, Indonesia. In this study the CO1 of mtDNA sequence data were used to investigate genetic variability within and between populations of mahseer. Twenty four tissue samples were collected for genetic analysis in the Batang Tarusan River. Genetic analysis revealed two different haplotypes were existed. The overall nucleotide and haplotype variability were low in all sampling sites. Hierarchical AMOVA analysis showed that mahseer populations form a single panmictic population with low FST= 0.02794; p = 0.418 and high gene flow among population sampling. Corroborated result by genetic analysis; there is a strong argument suggesting that the populations could be treated as a single stock unit.

A Current Update on the Distribution, Morphological Features, and Genetic Identity of the Southeast Asian Mahseers, Tor Species

“…Phenotypic variations within the Tor species are other factors of taxonomic confusion [ 3 , 104 ]. Recent studies have employed molecular markers to solve taxonomic ambiguity [ 13 , 15 , 105 ] and/or assess the genetic diversity of Tor [ 43 , 106 , 107 , 108 ]. Most of the studies have employed mitochondrial genes, while others have used nuclear DNA markers, such as microsatellites, for species identification.…”

“…In this regard, different mtDNA gene sequences have been used for species identification. The most frequently used is cytochrome oxidase I ( CO1 or COX1 ) [ 13 , 15 , 44 , 107 , 111 ] followed by cytochrome b ( Cyt b ) and ATPase subunits 6 and 8 ( ATPase 6/8 ) [ 1 , 106 , 108 ]. The other mitochondrial gene used in Tor studies is the 16S rRNA [ 1 ].…”

“…Second, we performed the phylogenetic analysis of complete and partial/short sequences of the COX1 gene. For this phylogenetic analysis, we extended the first phylogenetic analysis by adding seventy-one short/partial sequences of COX1 of Tor species obtained from NCBI databases ( Supplementary 2 ) [ 13 , 15 , 107 , 127 , 128 , 129 , 130 , 131 , 132 , 133 , 134 , 135 , 136 , 137 , 138 , 139 , 140 , 141 , 142 ]. Then, the phylogenetic trees were constructed using the method and model used in the first phylogenetic analysis.…”

“…A group of unique haplotypes was observed and subsequently proposed as a cryptic lineage of T. douronensis [ 111 ]. COX1 has also been used to study the genetic diversity of T. tambroides from Sumatra, Indonesia [ 107 ]; due to the highly conserved nature of the marker, very low genetic diversity was reported.…”