Study On Genetic Structure And Genetic Diversity Of Three Cultrinae Fishes In The Pearl River

The study analyzed the genetic structure and genetic diversity of wild fish collected from the Pearl River, including Culter Alburnus, Ancherythroculter lini Luo and Sinibrama macrops, by using the method of morphological marker, mitochondrial DNA marker and microsatellite molecular marker.In morphology: 1) The main differences of samples of C. Alburnus, which were collected from Xun River, Gui River, Rong River, Yu River, Zuo River and You River, Bei River and Xi River, were in the tail and trunk. In cluster analysis, the relationship between individuals from Zuo River and You River is close. 2) The main differences of samples of S.macrops collected from Gui River, Duliu River, Rong River, Yu River and Bei River were in the weight and trunk. Especially, some morphological characteristics of individuals from You River were at an advantage among others. In cluster analysis, the relationship between populations from Yu River and others was far apart. 3) The main differences of samples of A. lini Luo, which were collected from Rong River, Gui River, You River and Bei River,were in the head and trunk. Among, some morphological characteristics of population from Bei River were at a disadvantage. In cluster analysis, the relationship between populations from Gui River and You River was close. Likewise, the populations from Rong River and Bei River clustered into one clade either.In the results of the mitochondrial marker: 1) The overall population of C. Alburnus presented high haplotype diversity(Hd=0.87506/0.87357) and high nucleotide diversity(?=0.00700/0.0089). Whereas, genetic diversity of different populations varied greatly.Through the study of genetic differentiation(AMOVA and FST), the overall population of C.Alburnus did not have significant genetic differentiation(FST=0.1883/0.21929). Among the results of pairwise comparison, the populations of Gui River and You River had significant differentiation with others. Genetic distance showed that the phylogenetic relationshipamong different populations was still nearly. There was no specific difference in the haplotype phylogenetic tree and the network tree. 2) The overall population of S.macrops presented high haplotype diversity and high nucleotide diversity(Hd=0.70301/0.71456,?=0.00878/0.01569), while the genetic diversity index of population from Bei River was low(Hd=0.57143/0.95238, ?=0.00001/0.00177). Through the study of genetic differentiation(AMOVA and FST), the population of Bei River have significant genetic differentiation with other populations(FST=0.42144/0.58279). Also, genetic distance showed that the relationship between populations from Bei River and others was distant. In the haplotype phylogenetic tree and the network tree, the population of Bei River had significant distance from other populations. 3) The overall population of A. lini Luo presented high haplotype diversity and high nucleotide diversity(Hd=0.91600/0.847,?=0.00693/0.00569). Through the study of genetic differentiation(AMOVA and FST), the population of Bei River had significant genetic differentiation with other populations(FST=0.16594/0.16844). Genetic distance showed that the relationship between population from Bei River and others was distant.In the results of microsatellite molecular marker: 1) The analysis of C. Alburnus, 20 pairs of microsatellite primers, showed high polymorphism information content(0.7517)and expected heterozygosity heterozygosity(0.7803). The molecular variation illustrated that the inbreeding coefficient was high(Fis=0.62/Fit=0.59). The genetic differentiation among different populations was similar to the result of mitochondrial DNA. In addition to You River and Gui River, genetic differentiation of populations from Xun River and Yu River was higher than others. In the cluster analysis, Zuo River and You River clustered into one clade, the result was consistent with the morphological classification. 2) The analysis of S. macrops, 18 pairs of microsatellite primers, showed high polymorphism information content(0.8129) and expected heterozygosity heterozygosity(0.8327). The molecular variation illustrated that the inbreeding coefficient was high(Fis=0.60/Fit=0.56).The results of genetic differentiation and genetic were similar to the result of mitochondrial DNA. In the cluster analysis, the population of Bei River is far away from other population.3) The analysis of A. lini Luo, 20 pairs of microsatellite primers, showed highpolymorphism information content(0.7598) and expected heterozygosity heterozygosity(0.7765). The molecular variation illustrated that the inbreeding coefficient was high(Fis=0.45/Fit=0.43). The genetic differentiation among different populations was similar to the result of mitochondrial DNA. In the cluster analysis, the population of Bei River is far away from other population.