Abstract
The small abalone, Haliotis diversicolor supertexta, of the family Haliotidae, is one of the most important species of marine shellfish in eastern Asia. Over the past few decades, this species has drastically declined in Korea. Thus, hatchery-bred seeds have been released into natural coastal areas to compensate for the reduced fishery resources. However, information on the genetic background of the small abalone is scarce. In this study, 20 polymorphic microsatellite DNA markers were identified using next-generation sequencing techniques and used to compare allelic variation between wild and released abalone populations in Korea. Using high-throughput genomic sequencing, a total of 1516 (2.26%; average length of 385 bp) reads containing simple sequence repeats were obtained from 86,011 raw reads. Among the 99 loci screened, 28 amplified successfully, and 20 were polymorphic. When comparing allelic variation between wild and released abalone populations, a total of 243 different alleles were observed, with 18.7 alleles per locus. High genetic diversity (mean heterozygosity = 0.81; mean allelic number = 15.5) was observed in both populations. A statistical analysis of the fixation index (FST) and analysis of molecular variance (AMOVA) indicated limited genetic differences between the two populations (FST = 0.002, p > 0.05). Although no significant reductions in the genetic diversity were found in the released population compared with the wild population (p > 0.05), the genetic diversity parameters revealed that the seeds released for stock abundance had a different genetic composition. These differences are likely a result of hatchery selection and inbreeding. Additionally, all the primer pair sets were effectively amplified in another congeneric species, H. diversicolor diversicolor, indicating that these primers are useful for both abalone species. These microsatellite loci may be valuable for future aquaculture and population genetic studies aimed at developing conservation and management plans for these two abalone species.
Highlights
Pacific abalones are gastropod mollusks that are highly valued, especially in eastern Asia.Haliotis diversicolor supertexta, which belongs to the Haliotidae family, is a small abalone that varies in color and is a commercially important species distributed throughout the southern coasts of Korea, Japan, China and Taiwan [1,2]
The annual catch of this abalone has decreased drastically since its peak in 1997, and the commercial catch has declined by 90% over a 10-year period, reaching a historic low of approximately 12 tons in 2006 [3]. To compensate for these reduced fishery resources, enhancement practices have been initiated by the Jeju Province Fisheries Institute (JPFI) that involve the release of hatchery stock into natural coastal areas and have been ongoing since 2005 [4]
Because hatchery populations are often subjected to founder effects and bottlenecks that result in decreased genetic diversity, Bottleneck software, version 1.2.02 [52] was employed to test the bottleneck hypothesis under a two-phased model of mutation (TPM)
Summary
Pacific abalones are gastropod mollusks that are highly valued, especially in eastern Asia. The annual catch of this abalone has decreased drastically since its peak in 1997, and the commercial catch has declined by 90% over a 10-year period, reaching a historic low of approximately 12 tons in 2006 [3] To compensate for these reduced fishery resources, enhancement practices have been initiated by the Jeju Province Fisheries Institute (JPFI) that involve the release of hatchery stock into natural coastal areas and have been ongoing since 2005 [4]. A better understanding of the genetic structure of H. diversicolor supertexta would aid in the development of a more effective fishery management strategy for this species. We developed 20 novel polymorphic MS primer sets for H. diversicolor supertexta using 454 GS-FLX pyrosequencing, and we examined the genetic variability at these loci in a wild and released populations of this species. The polymorphic MS markers described here will be useful in future genetic studies aimed at understanding the genetic status and facilitating the conservation of two Pacific abalones, H. diversicolor supertexta and H. diversicolor diversicolor, in Korea
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
