Study On The Distribution Patterns And Genetic Diversity Of Crucian Carp Populations In Hunan Province

As an important freshwater fish in China,crucian carp also plays an indispensable role in the fishery economy of Hunan province.In this experiment,samples were collected from crucian carp in different sections of the four rivers of the Xiang-Zi-Yuan-Li River and Dongting Lake in Hunan province.Morphological markers were used to classify them,and differences in phenotypic traits and genes of each population were explored by microsatellite and mt DNA molecular techniques.This paper aims to grasp the status and dynamics of the genetic resources of crucian carp in Hunan province,that is,the genetic diversity,genetic differentiation information and the causes of genetic differentiation of crucian carp population in each water system section,to realize the scientific and adequate protection and sustainable development of the resources of crucian carp.The conclusions of this study are as follows:(1)By comparing the morphological data of the crucian carp population in the Four rivers of "Xiang Zi Yuan Li" and Dongting Lake in Hunan Province,one-way ANOVA showed that there were specific differences in morphological indicators among crucian carp populations.Still,such disputes could not reach the level of subspecies and could not be specifically distinguished.The covariance analysis showed that there was a significant difference in populations of crucian carp in five basins.Cluster analysis showed that there was no significant difference in the remaining groups except BMH and XYX(P > 0.05).The results of the principal component analysis showed that the first principal component accounted for 93.11%,and the main contributing traits were fish growth-related traits.Body length,head length,head height,tail stalk length,and tail stalk height were correlated with body shape traits.According to the LDA analysis,"Xiang,Zi,Yuan,and Li River" and Dongting Lake all converge into one body,except for a few groups.(2)Ploidy identification of the crucian carp group in the four rivers and Dongting Lake of Hunan Province,Triploid was the central part of this sample,and the proportion of triploid reached 63.23%.No tetraploid was found.All populations in Hunan province deviated from the Hardy-Weinberg equilibrium to varying degrees,which was characterized by excessive heterozygosity.Among them,CLJ,YJS,GZX,XJH,and XPX5 populations were negative values,which may have the heterozygous deletion.The largest population deviating from the Hardy-Weinberg equilibrium was WGX.A total of 55 haplotypes were detected in the mitochondrial COⅠ gene sequence(605bp)of the crucian carp population in Hunan province.Forty-eight haplotypes were detected in mitochondrial 16 SrRNA.According to the results of the maximum pseudo-natural tree(ML)constructed by the mitochondrial gene of the crucian carp population in Hunan province,the 55 haplotypes of COⅠ were separately clustered into HN16 and HN42,which were corresponding to(MK843659.1 and NC＿001606.1)to form a large branch.The largest cluster is 16 SrRNA48haplotypes,which are different from the most recent haplotype(KU668573.1)of crucian carp.AMOVA analysis showed that there was no population expansion of crucian carp in Hunan province recently.The results show that there is no distinct differentiation in the morphology of C.auratus in Hunan province,and the genetic diversity is at a relatively high level.