The Genetic Diversity Study Of Coilia Nasus Of Liaoning Province In China

In this study, Coilia ectenes from Liaoning province of China was the main object of study and Coilia ectenes from Taihu was the control group. From morphology, muscle biochemical composition, and molecular heredity three levels, making a comprehensive study on the genetic diversity of Coilia ectenes of the Liaohe(LH)Group, the Dayanghe(DYH) River population and the Yalujiang(YLJ) River population, respectively..The main results are as follows:(1)Forty frame scale parameters were counted to study the morphological differences of the DYH group、YLJ group and Taihu(TH) group by the traditional morphological data and the framework of measurement data in this study. As the application of principal component analysis, discrimination analysis, and clustering analysis three methods, the morphological differences were found form different groups of Coilia ectenes. The principal component analysis showed that the three populations of Coilia ectenes morphological differences which occur in the dorsal fin. The discrimination accuracy rate of the discrimination function was 100% in group and the comprehensive discrimination accuracy rate is 96.74% between groups, which can effectively distinguish the various groups belonging Coilia ectenes. The YLJ group and TH group clustered into one branch, in the form of two groups is close to. Therefore, morphogenetic variation had happened in the three groups of Coilia ectenes in different growth conditions. In conclusion, principal component analysis, discriminant analysis, and cluster analysis could identify the morphogenetic variation of them and, discrimination analysis could effectively separate the three groups.(2)The improvement of the frame data increased the discrimination accuracy between and within population discrimination. The improved frame data of Coilia ectenes in horizontal septum length(D13)’s indicated coefficient to the principle component 2 was 0.804>0.500, which was significantly contribution. Parameter D14-14′was selected from forty parameters of discrimination analysis so as to build discrimination function and improve the accuracy rate up to 100%, the accuracy rate between groups increased to 96.74%.The fish body in the framework was reflected fully by increasing the data of body thickness in different positions. There was an improvement on the existing framework of measurement method and worthiness for further study and discussion on the morphological study of other fish..(3)The difference was compared in the muscle nutritional composition of LH Group, the DYH group, the YLJ group and TH group of Coilia ectenes by the experiment of biochemical analysis. The crude protein content of the DYH and the YLJ group in Liaoning area was higher than other group, it was 84.29% and 84.27%, respectively. The difference was no significant(P>0.05). The crude fat content of Coilia ectenes descending in Liao Ning area: LH group>YLJ group>DYH river group, no differences among all groups(P<0.05). The coarse ash content of the YLJ group was lesser(3.76%) than other 3 groups, and there were no significant difference(P>0.05). YLJ group’SFA and PUFA content was the highest in Liao Ning province, its “EPA+DHA” was the highest of four groups, the differences were not signal(P<0.05). The total amino acid in the muscle of the YLJ group(TAA), total essential amino acid(TEAA) and total amino acids umami(TDAA) were significantly lower than those in the TH group, but is was significantly higher than that in the Liaoning group(P<0.05). Based on AAS analysis, Val and Met+Cys were the first and second limiting amino acid, respectively. Based on CS score analysis, the first limiting amino acid of four groups was “Met+Cys”. The second limiting amino acid of DYH group was Ile. The other three groups’ were val. YLJ group and DYH group’s EAAI was higher than others in Liao Ning area and it was 75.03% and 74.87%, respectively. But there was no significant difference(P>0.05).(4)The 34 tail Coilia ectenes mt DNA D-loop region part of 489 bp length sequence in the four geographical populations of LH, DYH, YLJ and TH were obtained from sequencing studies. The genetic diversity and genetic structure in the 4 groups of Coilia ectenes were analyzed. The results showed that the LH Group, DYH group and duck green river community Coilia ectenes haplotype diversity index were 0.85700, 0.84400 and 0.85700. The nucleotide diversity index were 0.00263, 0.00318 and 0.00351, and they were higher than that in TH group(0.41700 and 0.00091). YLJ group’s Tajima′s D number was-1.76179, and was significant deviation from neutral(P<0.05). For having experienced population expansion in its history. The range of genetic distance between the 4 groups was 0.00177~0.00323, it was significantly lower than distance between Coilia ectenes and Coilia grayi(0.0528). Fst number was 0.00543<0.05, no differentiation between the 4 groups was explained. The molecular phylogenetic tree results constructed with NJ and MP two methods supported the four groups did not occur in the differentiation between Coilia ectenes results.Results showed that no genetic differentiation happened in the four populations of LH Group, DYH group, the YLJ population and TH population. The genetic diversity of Coilia ectenes in Liaoning Province was richer than TH group and the most richest group in genetic diversity was YLJ group.