Abstract:
Climbing perch (Anabas testudineus) is a common tropical fresh- and brackish water fish species in Asia. Its
aquaculture has received attention in many Asian countries both as an emerging economic species and affordable
protein source. The Thai Department of Fisheries, therefore, has been interested in a selective breeding program
for this species. However, the lack of genetic data prevents such systematic breeding program. We performed
polymerase chain reaction restriction fragment length polymorphism (PCR-RFLP) analysis of mitochondrial D-loop
region to differentiate six wild and two hatchery populations of Anabas testudineus in Thailand (n = 21 - 29).
Analysis of variance indicated that hatchery populations had lower genetic diversity than wild populations (P =
0.01; average haplotype diversity = 0.52 and 0.10 in the wild and hatchery samples, respectively). However, there
was no clear relationship between the presence of haplotypes and geographic locations. Almost all populations
were genetically distinct. Analysis of Molecular Variance (AMOVA) indicated 57.83% among population genetic
variation. Pairwise FST values showed significant divergence in almost all population pairs, except for two pairs
(two hatchery samples; and Chonburi, CH and Ratchaburi, RT). Neighbor-Joining dendrogram based on Nei’s
genetic distance suggested high divergence between Sakhon Nakhon, SN and the remaining samples, but it did
not resolve the relationships among Nakhon Pathom (NP), RT, CH and Nakhon Si Thammarat (NS) representing
major river systems in Thailand. The PCR-RFLP of the mitochondrial D-loop region was an effective technique
to evaluate genetic diversity within and among populations. However, the level of polymorphism may not be
adequate to resolve the relationships among some populations. The results can aid the management of existing
genetic variation within hatcheries and the development of a base population for selective breeding.
