Genetic Diversity and Population Structure of Cultured and Wild Barramundi Lates calcarifer (Latidae) in Taiwan

Abstract

Barramundi, or Asian seabass Lates calcarifer, is a commercially important food fish with a wide geographic distribution in the Indo-West Pacific region. Despite its economic significance, particularly in Taiwan, information on the sources of fertilized eggs, fry and stock management practices remains largely unavailable. To ensure sustainable exploitation and effective selective breeding programs, assessing the genetic diversity and population genetic structure of barramundi is crucial. This study investigated the genetic diversity and population genetic structure of three cultured populations (Chiayi A, Chiayi B, and Tainan) and one wild-caught population in Taiwan using mitochondrial DNA cytochrome b and eight microsatellite loci as genetic markers. The analysis of haplotype network revealed that all populations shared an ancestral haplotype, yet each population had its own unique haplotype. Notably, the wild and cultured populations showed the largest genetic distance. However, overall, the genetic distances among all populations were small and similar. This finding suggests potential gene exchange, possibly through broodstock exchange practices between farms. The valuable genetic information obtained from this study holds the potential to improve aquaculture programs through targeted breeding initiatives and inform the development of sustainable management policies for barramundi.