Genetic diversity of blue spotted mudskipper Boleophthalmus boddarti populations in the Gulf Of Thailand using control region

Abstract

Genetic structure of blue-spotted mudskipper (Boleophthalmus boddarti) in the Gulf of Thailand was investigated, based on 320 base pairs of partial control region in mitochondrial DNA. A total of 179 samples were collected from 6 locations in the Gulf of Thailand, namely Rayong (RY), Chachoengsao (CH), Samut Songkram (SS), Petchburi (PB), Nakorn Sri Thammarat (NK), and Pattani (PT). There were 56 haplotypes, of which haplotype01 (H01) was the common haplotype, found in 88 samples from all locations. The numbers of variable sites were 60. Average haplotype diversity (h) and nucleotide diversity (π) were 0.7879 ± 0.0676 and 0.004899 ± 0.003389, respectively. AMOVA results showed that there was no significantly genetic differentation between the populations in the upper (Rayong, Chachoengsao, Samut Songkram, Petchburi) and lower (Nakorn Sri Thammarat, and Pattani) Gulf of Thailand (FCT = 0.02461, p > 0.05). However, there were significant difference between the populations within group (FSC = 0.05474, p <0.05.) and individuals within population (FST = 0.07800 p <0.01). Dendogram, generated from pairwise genetic distances, indicated the group of the populations from the inner Gulf of Thailand, consisting of Chachoengsao, Samut Songkram, and Petchburi, but the genetic structure of all populations was unclear. Network diagram of Median joining haplotype can classified into two groups. Group I contained haplotypes that found in all populations, including the common haplotype H01 that can be detected in the samples from all sampling sites, while most of member in group II were from the lower Gulf of Thailand and Rayong. For Mantel test, there was no correlation between genetic and geographical distances (p>0.05). The result showed no genetic structure of the Blue-spotted mudskipper in the Gulf of Thailand which should be the result of larval dispersal. Therefore, as far as the management plan of this fish species in the Gulf of Thailand is concerned, the species should be treated as single stock.