Genetic Structure And Molecular Genetic Markers Of Four Populations From Pelodiscus Sinensis

Pelodiscus sinensis, which is one of the six preponderant cultivated fishes in Zhejiang province, is regarded as very important fishery resources with high economic value. However, the germplasm resources of Pelodiscus sinensis are exposed to admixture and degeneration due to the booming Pelodiscus sinensis industry. The bulk of existing data for the representative populations of Pelodiscus sinensis in China focused on morphological character, breeding performance, immunity, etc. So far, little research has investigated the genetic differentiation and structure. For better protection and utilization of Pelodiscus sinensis, the knowledge of its population genetics is essential. This paper studied on genetic structure and molecular genetic markers of four populations in Pelodiscus sinensis (Taihu, Japan, Wubie and Taiwan populations) at DNA level with the methods of random amplified polymorphic DNA (RAPD) analysis, sequences analysis of mitochondrial cytochrome b gene (cyt b) and PCR-RFLP analysis of the first exon of tyrosinase gene (TYR).1. RAPD technique was applied to access the genetic variation within and among four populations in Pelodiscus sinensis. A total of 162 loci, including 110 polymorphic ones, were detected from the four populations by using 23 random primers. The results of analyses showed that the percentage of polymorphic loci in total DNAs of the four populations was 67.90% whereas it was 48.70%~52.94% in each population with the highest value in Taihu population and the lowest value in Japan population. The average genetic similarity index within each population ranked as Japan population (0.8469) >Taiwan population (0.8429) >Wubie population (0.8317) >Taihu population (0.8254). The maximal genetic distance occurred between Taihu and Wubie populations, while the minimum occurred between Taiwan and Wubie populations. The populations had an...