Loss of Genetic Variation in Hatchery Produced Haliotis Asinina Using AFLP and Allozyme Markers

Abstract

The genetic diversity and differentiation between wild and hatchery Haliotis asinina populations were tested by allozyme and AFLP techniques. The results from allozyme technique showed that there was a decline in mean number of alleles per locus, percentage of polymorphic loci and observed heterozygosity and a change in allele frequency in three loci, SDH-1, AAT-1 and EST-1. Allelic richness, percentage of polymorphic loci and observed heterozygosities ranged from 1.4 (0.2) to 1.2 (0.1), from 30 to 20, from 0.150 (0.104) to 0.140 (0.103) within both wild and hatchery H.asinina populations, respectively. Compared to wild population, the hatchery population from AFLP technique also showed that there was a reduction in effective number of allele, gene diversity, shannon's information index and percentage of polymorphic loci, they ranged from 1.5215 to 1.4675, from 0.2932 to 0.2609, from 0.4252 to 0.3778 and from 69.93 to 62.09, respectively. But low level of differentiation was found between wild and hatchery H.asinina populations. It is inferred that it is small effective population size inbreeding that results in loss of genetic variation in the hatchery H.asinina seed.