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1.
Horizontal starch gel electrophoresis was used to investigate genetic structures of four populations (Dandong, Rizhao, Ningbo and Guangzhou) of redlip mullet (Chelon haematocheilus). Fourteen loci of ten enzymes (G3PDH, IDHP, LAP, LDH, MDH, MPI, PGDH, PGM, SDH, and SOD) were identified. The proportions of polymorphic loci varied from 0.07 to 0.14. The average observed and expected heterozygosities ranged from 0.02 to 0.05 and from 0.02 to 0.04 respectively among the 4 populations. The average number of efficient alleles of each locus varied from 1.02 to 1.06. The genetic distance among populations was from 0.0004 to 0.0021. The genetic distances between Dandong, Rizhao and Ningbo populations were small, while those between Guangzhou population and other three populations were relatively high. The result indicated the possible divergence of redlip mullet between the South China Sea and the other sea areas of China due to geographic isolation.  相似文献   

2.
The genetic diversity of wild and hatchery populations of half-smooth tongue sole Cynoglossus semilaevis, based on observation of amplified fragment length polymorphism (AFLP) was described. Two hundred individuals from four wild populations, Laizhou (LZ), Weihai (WH), Qingdao (QD), Rizhao (RZ), and one hatchery population, Mingbo (MB), were screened using eight different AFLP primer combinations. A total of 384 loci were screened in the five studied populations. 48.4%, 51.3%, 50.7%, 49.3% and 45.8% of these loci were polymorphic among the individuals tested in the LZ, WH, QD, RZ and MB populations, respectively. The number of polymorphic loci detected by single primer combinations ranged from 17 to 35. The average heterozygosity of the LZ, WH, QD, RZ and MB populations was 0.072, 0.093, 0.092, 0.090 and 0.063, respectively. The WH population showed the highest genetic diversity in terms of total number of AFLP bands, total number of polymorphic bands, average heterozygosity and percentage of low frequency (0-0.2) polymorphic loci among all the populations, while the LZ population was the lowest among the wild populations. Compared with the wild populations, the hatchery population showed a low genetic viability.  相似文献   

3.
To investigate the genetic structures and differentiation of different wild populations of white croaker （Pennahia argentara）, horizontal starch gel electrophoresis was performed on 133 individuals collected from five different locations in China and Japan. The eleven enzyme systems revealed 15 loci, of which eleven were polymorphic. The percentage ofpolymorphic loci of white croaker populations varied from 6.67% to 53.3.3%; the mean observed and expected heterozygosity ranged from 0.0033 to 0.0133 and 0.0032 to 0.0191, respectively. The expected heterozygosity revealed a low genetic variability for white croaker in comparison with other marine fishes. The genetic distances between populations ranged from 0.00005 to 0.00026. A weak differentiation was observed within each clade and between clades; and no significant differences in gene frequencies among populations were observed in white croaker. Among the five populations, three Chinese populations showed more genetic diversity than that in Japanese populations.  相似文献   

4.
Isozyme Analysis on the Populations of Ruditapes philippinarum   总被引：4，自引：0，他引：4  
Horizontal starch gel electrophoresis was used to investigate the genetic structure of six populations of Ruditapes philippinarum in the coast of China. Seven enzymes revealed eleven putative loci, and seven of them were polymorphic, PGM^＊, MDH-1^ ＊, MDH-3^＊, LAP-1^＊, LAP-2^＊, MPI-1^＊ and MPI-2^＊. The proportions of polymorphic loci of R. philippinarum populations varied from 0.454 5 to 0.636 4. The values of observed and expected heterozygosities were from 0.039 4 to 0.154 5 and from 0.111 1 to 0.238 5, respectively. Nei＇s genetic distance varied from 0.003 3 to 0.025 3 with an average of 0.013 5. It is suggested that the genetic diversity of R. philippinarum was high.  相似文献   

5.
The genetic variation and differentiation of the razor clam Sinonovacula constricts distributed along the coast of China were studied through amplified fragment length polymorphism(AFLP)analysis. Six primer combinations generated 193 fragments. The He values varied from 0. 322 to 0. 463 and the percentage of polymorphic loci ranged from 74. 1% to 98. 4%, which indicates a high level of genetic diversity. Cluster analysis by Nei's pairwise distance grouped all specimens by geographical origins. AMOVA consistently showed that genetic variation among populations was 8. 71%, and most of the variation came from the genetic variation within populations(91.29%). Genetic differentiation among the six populations was moderate; pairwise FST ranged from 0. 0282 to0. 1480, which indicated that S. Constricts populations along the coast of China are genetically connected. Among all the six populations, the Beihai population is the mostly differentiated from the others, suggesting that Hainan Island and Leizhou Peninsula act as barriers to gene flow. All populations abide isolation by distance model as indicated by Mantel test, except for ZS(Zhoushan)and YQ(Yueqing)populations. Information obtained in this study will provide guidelines for conservation and fishery management of this species in the future.  相似文献   

6.
近江牡蛎两个野生种群的遗传多样性分析   总被引：1，自引：0，他引：1  
采用RAPD分子标记和rDNA-ITS1序列分析了近江牡蛎Crassostrea rivularis湛江官渡和阳江程村野生种群的遗传多样性。12个RAPD引物共扩增出8838条片段,157个位点,平均每个引物可产生13个位点,片段长度在200～2200bp之间。湛江种群和阳江种群的多态位点比例分别为89.62%和89.57%,遗传多样性指数分别为0.4170和0.4334。种群间平均遗传距离为0.0327,平均遗传相似性为0.9681,平均遗传分化系数为0.0437。得到近江牡蛎18S、5.8S部分序列和ITS1全部序列,其中ITS1序列片段长度为478～485bp,共有11个变异位点,两个为转换(A/G),其他为插入/缺失(A/-、T/-)。湛江和阳江种群各获得8个单倍型,其中有一个单倍型为两个种群共享。两个种群的CG碱基平均含量较高,分别为58.29%和58.41%。种群间的遗传分化系数0.0254。结果说明,近江牡蛎湛江种群和阳江种群间具有较高的遗传多样性和较低的遗传分化。  相似文献   

7.
Genetic diversity and differentiation of the oyster Crassostreaplicatula populations from China's coast were studied basedon seven microsatellite loci.All loci showed high polymorphism for all five C.plicatula populations,with an average number of alleleper locus of 19.3-27.9 and an average expected heterozygosity of 0.889-0.952.Significant departures from Hardy-Weinberg equilib-rium and deficits of heterozygotes were observed over most populations at each locus,which were fully explained by null alleles.Microsatellite analysis revealed significant subdivision in the C.plicatula populations.According to the neighbor-joining tree con-structed on the basis of the D,A distance,the five populations fell into three regional groups,showing a relatively homogeneous geneticstructure in geographically close populations.Assignation tests correctly assigned high percentages of individuals to their originalpopulations and groups,and also confirmed the existence of genetic differentiation among C.plicatula populations.The results ob-tained in this study will facilitate the formulation of appropriate fisheries management programs,stock identification and conservationof biodiversity for the species.  相似文献   

8.
Population genetics of the left-eyed flounder, Paralichthys olivaceus, including natural and cultured stocks distributed in the coastal waters near Qingdao of eastern maritime China, was analyzed in allozyme and RAPD. The results showed that among total 29 gene loci of 15 isozymes, 9 and 7 were po- lymorphic in natural and cultured stocks, respectively. The status of genetic diversity in P. olivaceus is low in terms of polymorphic loci in chi-square test and genetic departure index of Hardy-Weinberg equi- librium. More alleles in IDHP, CAT, GDH and Ldh-C allozymes were found in the fish, which could be used as markers in assortive breeding and distinguishing stock, population or species evolution. Total 88 and 86 RAPD bands ranging from 200 to 2 500 bp were recognized individually in average of 7.8–8.0 bands per primer. The genetic diversity in cultured stock is lower than that in natural ones showing an ob- viously decreasing genetic divergence. Therefore, effective countermeasures must be taken to protect ge- netic resources of marine cultured fishes. The 2 markers have their own pros and cons. Combining the 2 markers to investigate the genetic variation of populations is suggested. The results provide basic data of this flounder and they are useful for studying genetic improvement and genetic resources of the fish.  相似文献   

9.
应用AFLP方法,从64对引物中筛选出5对用于分析胡子鲇(Claris fuscus)厦门(XM)、江门(JM)、玉林(YL)等3个养殖群体共90个个体群体内、群体间遗传多样性。扩增共得到289条清晰谱带,引物多态性介于47.8%～63.8%,平均多态性比率为56.4%。胡子鲇群体总遗传杂合度(Ht)、遗传分化系数(Hs)、遗传分化度(Gst)和基因流(Nm)分别为0.161 1、0.153 6、0.051 1和8.501 8,表明胡子鲇多态性处于中等偏下水平,群体内部遗传分化系数较高,三个群体间无较大分化,群体间基因流动较好。其中,JM群体多态性比率、有效等位基因数Ne、Nei’s指数和Shannon指数都较XM群体和YL群体高,种内分化程度较好。对群体进行两两比较发现,XM群体和YL群体间分化程度最大,XM群体和JM群体次之,JM群体和YL群体最小。基于杂交优势,推断XM和YL群体繁殖所产生的后代将具有比亲代更为优良的性状。  相似文献   

10.
Genetic diversity and differentiation of the oyster Crassostrea plicatula populations from China’s coast were studied based on seven microsatellite loci. All loci showed high polymorphism for all five C. plicatula populations, with an average number of allele per locus of 19.3–27.9 and an average expected heterozygosity of 0.889–0.952. Significant departures from Hardy-Weinberg equilibrium and deficits of heterozygotes were observed over most populations at each locus, which were fully explained by null alleles. Microsatellite analysis revealed significant subdivision in the C. plicatula populations. According to the neighbor-joining tree constructed on the basis of the D A distance, the five populations fell into three regional groups, showing a relatively homogeneous genetic structure in geographically close populations. Assignation tests correctly assigned high percentages of individuals to their original populations and groups, and also confirmed the existence of genetic differentiation among C. plicatula populations. The results obtained in this study will facilitate the formulation of appropriate fisheries management programs, stock identification and conservation of biodiversity for the species.  相似文献   

11.
Blood clam, Tegillarca granosa, is an important shellfish in Chinese mariculture industry. Investigative research in this species, such as genetic linkage mapping, requires a large panel of molecular markers. In present study, a total of 89 polymorphic microsatellite markers were developed in T. granosa using the sequence database of Life Sciences Technology 454 next generation sequencing technology. All 89 loci were characterized in 20 individual clams from a natural population inhabiting Yueqing Gulf, Zhejiang Province, China. The number of alleles per polymorphic locus varied between 2 and 15, while the observed heterozygosity, expected heterozygosity and polymorphic information content varied between 0.000 and 1.000, 0.102 and 0.921, and 0.048 and 0.886, respectively. Of the 89 loci identified, 32 loci deviated significantly from Hardy-Weinberg equilibrium following Bonferroni correction. Thirty nine markers, which were shown to be polymorphic in a full-sibling family, were tested in Mendelian segregations. As expected, 32 loci were co-dominantly segregated in a Mendelian fashion. These novel developed microsatellite markers represent useful research tools for investigation of population genetic structure and genetic diversity in this species.  相似文献   

12.
In the framework of forest resources conservation, this study aims to understand the dynamic and the genetic structure of sessile oak forests in Calabria, Italy. Two old populations of sessile oak(Quercus petraea(Mattuschka) Liebl.) from two areas of Sila and Aspromonte massifs in Calabria were analyzed for genetic diversity and population structure based on 6 nuclear simple sequence repeat(nSSR) and 4 chloroplastic SSR(cpSSR) loci. The populations displayed high amount of genetic diversity, which was toughly structured according to their geographical origins. Number of alleles at SSR loci ranged from 11 to 20 with an average of 13.5 per locus. Gene diversity(expected heterozygosity, He) estimates ranged from 0.575 to 0.834 with a mean of 0.749. The observed heterozygosity(Ho) was on average 0.458 ranging from 0.150 to 0.682. Polymorphism information content(PIC) values ranged from 0.625 to 0.865 with an average of 0.787. The analysis of molecular variance(AMOVA) highlighted a significant higher estimated variance within populations compared to among populations. Finally, the analysis of haplotypes by using cpSSR suggested a higher diversification in the population from Sila. Hierarchical clustering analysis grouped the genotypes into two major clusters, which agreed with the geographic origin of populations, and was confirmed by the Discriminant Analysis of Principal Components(DAPC). The first cluster included plants/population from Sila massif, while the second encompassed mostly plants/population sampled in Aspromonte massif. Finally, model-based clustering by STRUCTURE analysis also supported the presence of clear genetic structuring in the collection with two major populations(K=2) supported to PCoA analysis as well. Finally, our data indicated the Aspromonte population as a marginal forest with fragmented distribution suggesting different strategies of preservation than in Sila massif.  相似文献   

13.
利用近源物种马氏珠母贝的EST-SSR引物对企鹅珍珠贝DNA进行扩增,获得7对可扩增出目标条带的近缘分子标记,分析野生群体(YS)和养殖群体(YZ)企鹅珍珠贝的遗传多样性。结果显示,7个位点共获得26个等位基因;野生和养殖群体的等位基因数分别为3~5和3~4,平均期望杂合度(He)分别为0.623 5、0.496 8;平均观测杂合度(Ho)分别为0.431 8、0.302 8;HNUPM047位点的多态信息含量较低,为0.446 7,其他位点均在0.5以上,说明该遗传标记可提供比较丰富的遗传信息。表明养殖群体遗传多样性水平低于野生群体。  相似文献   

14.
Knowledge of population genetic structure plays an important role in fisheries management.In this research,In-ter-Simple-Sequence-Repeat(ISSR)markers were employed to evaluate the genetic structure of Japanese sardinella(Sardinella zun-asi)populations in the Northwest Pacific.Eighty seven individuals from 5 locations were screened using 4 highly polymorphic prim-ers.A total of 173 polymorphic loci were detected out of 191 loci amplified.Small but significant genetic differentiation was de-tected between the Chinese and Japanese populations by both AMOVA and pairwise FST analyses,which was further supported by cluster analysis.We consider that climate change during glaciations should be responsible for the genetic differentiation.Isolation by geographic distance among populations was observed,indicating that the distance might also lead to the genetic differentiation.However,no genetic structure was found within the populations off both the Chinese and Japanese coasts,indicating a high-level along-coast gene flow,which might result from ocean current transport and common ground for over-wintering.  相似文献   

15.
用同工酶电泳方法研究广东省官渡、阳江和汕尾的近江牡蛎(Ostea rivularis)的遗传变异。分析了11种同工酶20个的位点,其中出现13个位点显示为多态。结果表明官渡、阳江、汕尾种群的多态位点比例分别为0.200、0.200、0.500。官渡和阳江种群间,官渡和汕尾种群间以及阳江和汕尾种群间的遗传距离(D)分别为0.0451,0.1125,0.1088。  相似文献   

16.
Japanese flounder is one of the most important commercial species in China; however, information on the genetic background of natural populations in China seas is scarce. The lack of genetic data has hampered fishery management and aquaculture development programs for this species. In the present study, we have analyzed the genetic diversity in natural populations of Japanese flounder sampled from the Yellow Sea (Qingdao population, QD) and East China Sea (Zhoushan population, ZS) using 10 polymorphic microsatellite loci and cytochrome c oxidase subunit I (COI) sequencing data. A total of 68 different alleles were observed over 10 microsatellite loci. The total number of alleles per locus ranged from 2 to 9, and the number of genotypes per locus ranged from 3 to 45. The observed heterozygosity and expected heterozygosity in QD were 0.733 and 0.779, respectively, and in ZS the heterozygosity values were 0.708 and 0.783, respectively. Significant departures from Hardy-Weinberg equilibrium were observed in 7 of the 10 microsatellite loci in each of the two populations. The COI sequencing analysis revealed 25 polymorphic sites and 15 haplotypes in the two populations. The haplotype diversity and nucleotide diversity in the QD population were 0.746±0.072 8 and 0.003 34±0.001 03 respectively, and in ZS population the genetic diversity values were 0.712±0.047 0 and 0.003 18±0.000 49, respectively. The microsatellite data (F_st =0.048 7, P<0.001) and mitochondrial DNA data (F_st =0.128, P<0.001) both revealed significant genetic differentiation between the two populations. The information on the genetic variation and differentiation in Japanese flounder obtained in this study could be used to set up suitable guidelines for the management and conservation of this species, as well as for managing artificial selection programs. In future studies, more geographically diverse stocks should be used to obtain a deeper understanding of the population structure of Japanese flounder in the China seas and adjacent regions.  相似文献   

17.
Blood clam, Tegillarca granosa, is an important shellfish in Chinese mariculture industry. Investigative research in this species, such as genetic linkage mapping, requires a large panel of molecular markers. In present study, a total of 89 polymorphic microsatellite markers were developed in T. granosa using the sequence database of Life Sciences Technology 454 next generation sequencing technology. All 89 loci were characterized in 20 individual clams from a natural population inhabiting Yueqing Gulf, Zhejiang Province, China. The number of alleles per polymorphic locus varied between 2 and 15, while the observed heterozygosity, expected heterozygosity and polymorphic information content varied between 0.000 and 1.000, 0.102 and 0.921, and 0.048 and 0.886, respectively. Of the 89 loci identified, 32 loci deviated significantly from Hardy-Weinberg equilibrium following Bonferroni correction. Thirty nine markers, which were shown to be polymorphic in a full-sibling family, were tested in Mendelian segregations. As expected, 32 loci were co-dominantly segregated in a Mendelian fashion. These novel developed microsatellite markers represent useful research tools for investigation of population genetic structure and genetic diversity in this species.  相似文献   

18.
Fenneropenaeus penicillatus (redtail shrimp) is an important marine commercial animal in China. Recently, its resources have been depleted rapidly as a result of, for example, over-exploitation and environmental degradation of spawning grounds. Therefore, we analyzed the genetic diversity and differentiation of nine wild populations of F. penicillatus of China (Ningde, Lianjiang, Putian, Xiamen, Quanzhou, Zhangpu, Dongshan, Nanao, and Shenzhen populations) by amplified fragment length polymorphism (AFLP) technology, to provide genetic information necessary for resource protection, rejuvenation, artificial breeding, and sustainable use of the resource. Eight AFLP primer pairs were used for amplification, and 508 bands were detected among the populations. The results show that the percentage of polymorphic loci (P) ranged from 41.34% to 63.58%; the Nei’s gene diversity (H) of the populations was 0.119 4-0.230 5; and Shannon’s Information Index (I) was 0.184 1-0.342 5. These genetic data indicate that the genetic diversity of F. penicillatus was high. The genetic differentiation coefficient (GST=0.216 2) and gene flow (Nm=1.812 4) show that there was a high level of genetic differentiation and a moderate level of gene flow among populations. More studies on the genetic differentiation mechanism of F. penicillatus along the south-eastern coast of China need to be conducted to find more effective scientific protection strategies for the conservation of F. penicillatus genetic resources.  相似文献   

19.
The amplified fragment length polymorphic DNA (AFLP) technique was adopted to estimate the population genetic polymorphism among 30 sporophytes of Laminaria japonica collected from a cultivating farm in Rongcheng,China.Three methods were used for genomic DNA extraction from Laminaria japonica sporophyte and only the products obtained using the improved genomic DNA extraction kit method proved qualified for AFLP analysis.The parameters of the method were optimized.Samples of forty milligrams and the cell lysis time of 120 min were suggested to replace the parameters recommended by the manufacturer.Thirty individuals of Laminaria japonica from the same cultivating site were investigated using one pair of selective primers.A total of 21 loci were obtained and 17 of them were polymorphic.The mean percent age of polymorphic loci of this population was 80.95%.The Nei's gene diversity (H) within this population was 0.3028 and the average Shannon's Information index (I) was 0.4498.A genetic distance matrix among different individuals was constructed as well.Through this study,an applicable AFLP genetic analysis working system for Laminaria japonica sporophyte was established.The results of this research also revealed a high level of genetic diversity within the studied population.  相似文献   

20.
Amplified fragment length polymorphisms(AFLP) markers were developed to assess the genetic variation of populations and clones of Rhopilema esculentum Kishinouye(Scyphozoa,Rhizostomatidae).One hundred and seventy-nine loci from 56 individuals of two hatchery populations and two wild populations were genotyped with five primer combinations.The polymorphic ratio,Shannon’s diversity index and average heterozygosity were 70.3%,0.346 and 0.228 for the white hatchery population,74.3%,0.313,and 0.201 for the red hatchery population,79.3%,0.349,and 0.224 for the Jiangsu wild population,and 74.9%,0.328 and 0.210 for the Penglai wild population,respectively.Thus,all populations had a relatively high level of genetic diversity.A specific band was identified that could separate the white from the red hatchery population.There was 84.85% genetic differentiation within populations.Individual cluster analysis using unweighted pair-group method with arithmetic mean(UPGMA) suggested that hatchery populations and wild populations could be divided.For the hatchery populations,the white and red populations clustered separately;however,for the wild populations,Penglai and Jiangsu populations clustered together.The genetic diversity at the clone level was also determined.Our data suggest that there are relatively high genetic diversities within populations but low genetic differentiation between populations,which may be related to the long-term use of germplasm resources from Jiangsu Province for artificial seeding and releasing.These findings will benefit the artificial seeding and conservation of the germplasm resources.  相似文献   

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