Tudy On Genetic Markers Of Wild And Cultured Pelteobagrus Fulvidraco

Pelteobagrus fulvidraco is an important economic species of freshwater fish in East Asia. In our study, the germplasm resources of four wild and cultured Pelteobagrus fulvidraco populations were investigated using morphological markers,cytological markers,biochemical markers and SSR molecular markers, so we can understand its germplasm resources status, provide some scientific basis database and theoretical supports not only for Jiangxi Pelteobagrus fulvidraco germplasm resources protection and utilization, but also for the subsequent development of Pelteobagrus fulvidraco in deeper study. The main results are as follows:1、 Traditional morphological data and truss network data were combined to conduct a multivariate analysis to study the morphological variations and phylogenesis of four wild and cultured Pelteobagrus fulvidraco populations. comparing with wild and cultured populations of Pelteobagrus fulvidraco, we found that morphological variation is not significant in wild and cultured populations of Pelteobagrus fulvidraco. In addition, Cluster analysis showed the morphology of YSDSF YZGW and YSNC population are closer, there are morphological differences between YZJJ population and other three populations of Pelteobagrus fulvidraco.Principal component analysis indicated morphological variations of the four populations mainly came from the head,tail and the change of fish’s axis.Discriminate analysis showed the synthetic discriminating accuracy in the four populations is79.6%.2、Wild and cultured Pelteobagrus fulvidraco in Jiangxi Province was analyzed by making chromosome specimens with the kidney cell. The results showed that wild and cultured Pelteobagrus fulvidraco in Jiangxi Province had a diploid number of52chromosomes.The karyotype formula was2n=20m+14sm+14st+4t.NF=86.Cultured populations of Pelteobagrus fulvidraco in Jiangxi Province probably comes from wild populations. Comparing with the karyotypes of other fishes,we found that Pelteobagrus fulvidraco belonged to low specialization group in fish evolution history.3、Comparative analysis on the isozyme patterns of LDH and EST in six tissues(heart,liver,spleen,gills,muscle and kidney)fromwild and cultured Pelteobagrus fulvidraco was carried out to prode into their distribution by Polyacrylamide Gel Electrophoresis(PAGE).The result shows that two kinds of isozymes are no differences between the wild and cultured populations. Cluster analysis showed the genetic relationship of YZGW and YSDSF are closest which indicated that it was possible that YZGW was a branch of YSDSF population. Relatively speaking,The differences of EST isozyme are more significant than LDH isozyme in four populations, and the two isozymes were found in these tissues and have obvious tissue-specific.This specificity may be associated with differernt function of isozymes in all the tissues and organs.4、We have done some researches on the genetic diversity of four wild and cultured Pelteobagrus fulvidraco populations which were YSNC、YSDSF、YZGW and YZJJ by using SSR molecular markers. The results showed that (1)Optimizing the reaction conditions, we find10pairs of SSR primers are effective and get8microsatellite loci which all have polymorphism.Polymorphism ratio is80%.113alleles were totally detected in8microsatellite loci ranging from70bp to329bp in length,2to7alleles wereamplified in each locus.The average number of alleles in each locus was3.53.(2)The level of genetic variability was moderate in the four populations.The genetic diversity of wild populations of Pelteobagrus fulvidraco is slightly higher than the cultured.Mean polymorphic information contents of the four populations were0.4549,and the average effective alleles were2.3013.The values of average observed and expected heterozygosity were0.4251and0.5523respectively.The mean observed heterozygosity was lower than the corresponding mean exppected heterozygosity,which showed inbreeding happened in some extent in four Pelteobagrus fulvidraco populations.(3)Genetic differentiation between the four populations was moderate,the average number of Fst was0.1349,and the average number of Nm was1.6034.(4)The genetic similarity distance was from0.0664to0.0820;The clustering result showed that the genetic relationship of YZGW YSDSF and YSNC population are closer than YYJJ population.