Investigating of the genetic diversity of black halva fish (Parastromateus niger) and sokla (Rachycentron canadum) in the Persian Gu lf using 16SrRNA gene sequencing

Abstract

Introduction: Molecular identification of the economic species of the Persian Gulf is
necessary to protect the resources of endemic species and to introduce new species. This
research was conducted with the aim of determining the genetic diversity and genetic
distance of two species of Sokla and Black Halva in the Persian Gulf compared to other
samples from nearby locations such as the Indian Ocean and far away locations such as the
Pacific Ocean.
Materials & Methods: 120 samples from each of the waters of the two regions of Bandar
Mahshahr in Khuzestan province and Bandar-Abbas in Hormozgan province and
corresponding to the main fishing areas of the desired species were randomly collected and
after separating two grams of tissue from each fin. The fish were placed in two milliliter
microtubes with ethanol and transferred to the laboratory. A portion of the mtDNA genome
called 16srRNA was successfully amplified and sequenced, and approximately 560 reliable
base pairs were selected for phylogeny analysis.
Results: As a result of comparing the sequences, the sequences of black halva specimens
from Bandar -Abbas and Bandar Mahshahr were found together with samples from
Malaysia and Japan with a total of five haplotypes in one Clyde. However, one sample from
Bandar-Abbas differed from the rest of the samples with a high genetic difference (0.072).
The second Clyde was divided into two clusters with respect to Sokla species, where with
samples from Bandar-Abbas and Khuzestan showing up as one haplotype in the first cluster,
and samples from the Blue Zone of Pakistan and America as two separate haplotypes in the
second cluster.
Conclusion: In this research, it can be concluded that overfishing and the possibility of loss
of alleles, increase in inbreeding between breeding populations, their possible entry into the
sea, the presence of physical barriers and special nursery areas and as a result in a reduced
tendency to migrate is one of the important factors for reducing the genetic diversity of the
studied species in the Persian Gulf region.