The Population Genetic Diversity Analysis Of Hemiculter Leucisculus From Different Water Systems In Henan Province

Hemiculter leucisculus is a fresh water fish in Cyprinidae family widely distributing in the main river basin and lakes,and inhabit in the upper and middle layers of water.The phylogenetic biogeography of freshwater fishes is important for understanding the biological significance of the evolution of river basins or watersheds.In the same way,River evolution plays an important role in the formation of spatial patterns of genetic diversity in freshwater fishes.However,the relative biogeographic patterns and causes of freshwater fishes in different water systems in Henan have not been well understood.In order to estimate and compare the genetic diversity and population structure of H.leucisculus that were located in the Yellow River Basin,Huaihe Basin,and Weihe River Basin in Henan Province,we used CO I and Cyt b sequences to estimate population genetic parameters,test for demographic fluctuations.discuss the causes of spatial patterns of genetic diversity distribution and the relationship with geographical environment;understand the resources present situation of H.leucisculus of the different water systems;Analysis of the protection of key areas,to provide reference basis for the germplasm resources protection and management.The main results were as following:1.Genetic diversity and population genetic structure of H.leucisculus based on CO I gene.The total haplotype diversity(h)of 19 geographic populations was 0.857 and the total nucleotide diversity(?)was 0.00458.The HS population with the highest haplotype diversity and nucleotide diversity(h= 0.926,?= 0.0056),whereas QLH population with the lowest haplotype diversity and nucleotide diversity(h= 0.300,?= 0.0010).The average haplotype diversity(h)of the the Yellow River,Huai River and Wei River system were 0.865,0.815,0.831 respectively,and the average nucleotide diversity(?)were 0.00538,0.00376,0.00363 respectively.Genetic differentiation among the populations was low or no significant,but there was significant genetic differentiation between QLH population and other populations.Analysis of molecular variance(AMOVE)among river systems,The results showed that genetic variation was 72.49%(P<0.0001)mainly from river systems within populations,indicating that there was no obvious genetic variation between the populations of the water systems.Phylogenetic tree and haplotype network analysis also showed that there was no obvious drainage pattern and geographical distribution among the genetic lineages.Tajima's D test,Fu's FS test and mismatch analysis showed the H.leucisculus had not experienced recent historical population expansion.Bayesian skyline plot revealed that the effective population size of the species has increased significantly 0.02 million years ago.2.Genetic diversity and population genetic structure of H.leucisculus based on Cyt b geneThe total haplotype diversity(h)of 19 geographic populations was 0.903 and the total nucleotide diversity(?)was 0.0077.The HS population with the highest haplotype diversity and nucleotide diversity(h = 0.941,?= 0.0097),whereas QLH population with the lowest haplotype diversity(h = 0.372)and ZK population with the lowest nucleotide diversity(? = 0.0021).The average haplotype diversity(h)of the the Yellow River,Huai River and Wei River system were 0.928,0.809,0.898 respectively,and the average nucleotide diversity(?)were 0.01123,0.00428,0.00514 respectively.Genetic differentiation among the populations was low or no significant,but there was significant genetic differentiation between QLH population and other populations.The results of AMOVA analysis,whether it is a as a geographical group,or different geographical water groups,the result is the main genetic variation within populations,and not from different geographical groups or groups in different populations.Phylogenetic tree and haplotype network analysis also showed that there was no obvious correlation between the genetic distance and the geographical distance,indicating that there was no genetic isolation and population differentiation between geographical populations.Neutrality test and mismatch analysis showed the H.leucisculus had not experienced recent historical population expansion.Bayesian skyline plot revealed that the stock of H.leucisculus has declined dramatically 0.036-0.0041 million years,and the effective population size of H.leucisculus has increased significantly 0.003 million years ago.The effective population of the Yellow River system declined obviously in 0.05 million years,and 0.004 million years later,the effective population showed an increasing trend.The genetic diversity of H.leucisculus in Yellow River was high,and the genetic diversity of Huaihe River and Weihe River was low.AMOVA analysis showed that genetic variation within population is the main source of the total variation.Population dynamics showed that 19 population of H.leucisculus did not occur the population expansion.Phylogenetic analysis also showed that there were no lineages corresponding to geographical lineages,and that each haplotype was star shaped and distributed in each river system.The main reason for the geographical distribution of the species is that the time of the river invasion,as well as the geographical separation and climate changes during the Quaternary glacial period.Genetic diversity of H.leucisculus was low and natural resources was in a recession.QLH population showed significant genetic differentiation and low genetic diversity,indicating that the resources was threatened to a certain extent.It is recommended that the QLH population be preferentially protected as a single management unit(MU).It is recommended that the relevant departments vigorously promote the importance of protecting the living environment of fish,improve people's resources protection,environmental protection awareness,reduce human disturbance and damage to fish resources.