Phylogeographies Of Zacco Platypus Populations From Different Places In China And The Biological Study Of Yongjiang Population

The phylogeographies of Zacco platypus were investigated in the present study,and the specimens collected from 8 different places in China,including Anyang?AY,Henan Province?,Beijing?BJ?,Dalian?DL,Liaoning Province?,Hangzhou?HZ?,Wenzhou?WZ?and Ningbo?YJ??Zhejiang Province?,Huangshan?HS?and Xuancheng?XC??Anhui Province?.The phylogeographic pattern,genetic diversity,population genetic structure and historical demography of Z.platypus were analyzed.In addition,the biological study on 411 Z.platypus population,collected in Ningbo from 2015 to 2016,were discussed in age composition,sex ratio,body volume and fecundity.The major results are summarized as follows:1.The phylogeographic patterns of Z.platypus were examined based on the mitochondrial COI gene.A total of 191 individuals of Z.platypus obtained from 8places in China were sequenced for the analyses and then grouped into 38 defined haplotypes with undetectable geographic structure.The phylogenetic tree?NJ tree?displayed distribution pattern of 3 main lineages exhibted which was as similar as that of network showed.Low haplotype diversity and low nucleotide diversity revealed that the level of genetic diversity was low.Analyses of pairwise Fst,Exact test and molecular variance?AMOVA?revealed significant genetic differentiation and lack of gene flow among the 8 Z.platypus groups,implying that Z.platypus was nonrandom mating.But there was no significant genetic differentiation between BJ group and DL group.Both mismatch distribution analysis and neutrality tests hinted that there was no evidence to prove the population expansion for Z.platypus groups,but BJ,DL and WZ group appearing significant negative value in neutrality tests showed these groups might experience population expansion.2.The phylogeographic patterns of Z.platypus were examined based on the mitochondrial Cytb gene.A total of 191 individuals of Z.platypus obtained from 8localities were sequenced for the analyses and grouped into 54 defined haplotypes with undetectable geographic structure.The phylogenetic tree?NJ tree?revealed a distribution pattern of 3 main lineages and network showed the similar structure as NJ tree.In genetic diversity,haplotype diversity was high and nucleotide diversity was low.Analyses of pairwise Fst,Exact test and molecular variance?AMOVA?revealed significant genetic differentiation and lack of gene flow among the 8 Z.platypus groups,implying that Z.platypus was nonrandom mating.But there was no significant genetic differentiation between BJ group and DL group.Both mismatch distribution analysis and neutrality tests revealed that there was no evidence to prove the population expansion for Z.platypus groups,but DL and WZ group appearing significant negative value in neutrality tests showed these groups might experience population expansion.In conclusion,Cytb gene had higher sensitivity in testing genetic diversity and population genetic structure,and COI gene was sensitive in analyzing historical demography,while both of them have consistency in reflecting phylogeographic pattern.3.Z.platypus population,411 individuals collected at Tingxia Reservoir in Ningbo,was composed of three groups,Age1,Age 2 and Age 3.Group Age 2 was the main part of this population.The length?L?of Z.platypus population ranged from 7.0to 14.0 cm and the weight?W?of Z.platypus population ranged from 4.0 to 36.0g.According to the gender the curve fittings were as follows to show the relation between body-length and weight:W_?=2×10^-5L^2.9337,W_?=3×10^-5L^2.8471.The proportion of male and female was 127:238,which showed a significant difference comparing with theoretical ratio 1:1 a Chi-square test.The individual absolute fecundity of the population ranged from 532 grain to 13717.89 grain,and the average was 2850.39±2107.49;the individual relative weight fecundity of the population was91.25 to 1027.56 grain/g,with a mean value of 363.73±178.55 grain/g.The multiple stepwise regression equation of individual absolute fertility was F=3392.97+1563.72W_G-1267.53A,R²=0.381;the multiple stepwise regression equation of the relative fertility of individual body length was F_L=474.58+148.273W_G-154.557A,R²=0.316;the multiple stepwise regression equation of relative fertility of individual weight was F_W=646.56-141.42 A,R²=0.129.These biological data enriched the information of Z.platypus and references for rational utilization of natural resources.