The Application Of Molecular Markers In Genetic Breeding Of Abalone And Scallop

In this research, molecular markers, RAPD AFLP and ISSR are applied to investigate and solve problems involved in genetic breeding in abalone and scallop.Haliotis discus hannai and H. discus discus were proved to be subspecies on the levels of genome for the first time, and their hybrids with strong heterosis showed more low-frequency loci and higher variation. In order to protect the threatened stock of H, discus hannai, 12 specific markers were found to distinguish it from its hybrids efficiently. A new method using dominant markers was developed to identify different families from mixed population, which offered a convenient way to breed pure lines. To reveal the influence of stock size on population structure, groups with different number of parents were analyzed, and it was indicated too fewer parents easily caused the loss of rare loci and temporal increase of heterozygosity. Through pseudo-testcross mapping strategy, the linkage maps of H, discus were constructed, providing new way to construct shellfish map using existing biological material. By ISSR technique, we found the rich microsatellites distributing in scallop. And the inheritance and segregation of microsatellite markers from two species, Chlamys farreri and C. nobilis to their hybrid were studied, it proved the two species with different chromosomes could be fertilized successfully, whereas their hybrid was more similar to one parent, C. farreri.