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1.
额尔齐斯河银鲫形态学及COI基因序列分析 总被引：1，自引：0，他引：1
采用传统形态学方法和线粒体COI基因序列分析对额尔齐斯河银鲫(Carassius auratus gibelio)两个群体的形态和遗传差异进行了比较。结果显示:通过对8个可量性状和20个框架数据的主成分分析可以看出,两个群体分别占据两个不相重叠的区域,两个群体在形态上存在明显分化。COI基因序列分析显示,两群体之间遗传距离为0.012,群体间遗传距离是群体内最大遗传距离的4倍,两群体间在编码的氨基酸序列上出现了一处替换,群体遗分化指数值为0.96078,基因流值为0.01,表明群体间缺乏基因交流,群体间有明显的遗传分化。 相似文献
2.
Sequence variation of the mitochondrial DNA was analyzed to examine the genetic structure and demographic history of the goldlined
spinefoot Siganus guttatus in the northwestern Pacific. In total, 451 nucleotide sequences spanning from the tRNAThr gene to the middle of the control region were determined from 254 specimens collected from five localities; three in the
Ryukyu Islands (Okinawa, Miyako, and Ishigaki Islands), Taiwan, and Cebu Island of the Philippines; 73 variable sites and
75 haplotypes were detected. Our results showed restricted gene flow and genetic differentiation among all populations, with
the exception of genetic homogeneity between the Miyako and Ishigaki populations; that is, this species will be able to cross
between Miyako and Ishigaki (ca. 120 km) by the transport of pelagic larvae, and gene flow between Okinawa and Miyako/Ishigaki
Islands (ca. 330–450 km) is restricted. A non-dispersal strategy will lead to restricted gene flow and genetic structuring
in S. guttatus. Both the neutrality tests and the mismatch distribution indicated that S. guttatus might have been in populations at demographic equilibrium. This suggests that population range expansion may have been restricted
owing to a non-dispersal strategy that may have restrained S. guttatus from demographic expansion after glaciation. The result will be of fundamental importance for resource management of this
species. 相似文献
3.
河鲈为我区优质经济鱼类之一,在我国仅分布于新疆阿勒泰地区。为更好的保护和合理开发利用这一有限资源,我们基于mtDNA控制区序列对额尔齐斯河-乌伦古河水系的5个野生群体进行了遗传多样性和遗传结构进行了研究。PCR-SSCP标记结果显示,18个单倍型分布于5个群体的100个个体中。对这18个单倍型个体的mtDNA控制区序列克隆和测序,最终确定13个单倍型,检测到14个变异位点,占分析序列的1.60%。河鲈总种群表现高的单倍型多样度（0.942±0.034）和偏低的核苷酸多样度（0.00242±0.00450）。Tajima’s D和Fuand Li’s D指数的估算结果显示,河鲈5个群体遗传分化不显著（P〉0.1）,具有较稳定的种群结构。YBW,BEJH和LSW群体间存在着一定的基因流（Nm〉1）,WLGH群体与其他群体间的基因流水平低（Nm〉0.6）,存在着由于遗传漂变而产生分化的危险。5个群体间的单倍型序列差异为0.003,说明单倍型间未出现分化。 相似文献
4.
Can female preference drive intraspecific diversity dynamics in brown trout (Salmo trutta,L.)? 
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下载免费PDF全文 Intraspecific diversity can be strongly impacted by the dynamics of reproductive isolation during secondary contacts. The high levels of hybridisation and introgression between Atlantic and Mediterranean lineages in contemporary populations of brown trout in the Northern part of the French Alps are a good case in point. After a long period of allopatry, which one assumes has facilitated their divergent phenotypic and genetic evolution, man has removed a geographical reproductive barrier via stocking the Atlantic lineage in the Mediterranean area, thereby potentially enabling gene flow between native and non native populations. We investigate how much a prezygotic reproductive behaviour, that is female preference for male phenotype, can influence hybridisation in natural environments, using subaquatic video recording of reproduction. Our statistical model indicates that female preference appears to be largely heterogamous: females tend to select dissimilar males with respect to their own phenotype; thus, rather than acting as a barrier to gene flow, female preference is favouring gene flow between lineages that have been artificially placed in sympatry. This finding based on observational data is in agreement with previously reported genetic data, high levels of hybridisation between the lineages. We suggest that a knowledge of reproductive behaviour in natural environments is an essential tool for biodiversity managers to assess the potential risks associated with the introduction into recipient populations of non‐native lineage fish at the intraspecific level. 相似文献
5.
ABSTRACT: The genetic diversity and population structure of Cyclina sinensis were assessed using amplified fragment length polymorphism (AFLP). Three hundred and fifty-four AFLP loci were analyzed in 160 individuals collected from Lvshun, Lianyungang, Yueqing and Dongxing of coastal China. High levels of genetic diversity were detected, where the percentage of polymorphic loci and average expected heterozygosity ranged 88.4–98.9% and 0.304–0.365, respectively. Analysis of molecular variance showed that variation among populations (24.4%) was highly significant ( P < 0.001). Accordingly, the global fixation index ( θ B ) averaged over loci was high (0.205). The large genetic differences among populations indicate restricted gene flow, congruent with limited dispersal capability of C. sinensis . The unweighted pair group method with arithmetic mean (UPGMA) tree topology constructed on the basis of Nei's genetic distances between populations showed a clear separation of the northern two populations from the southern two populations, suggesting that gene flow between the northern and southern regions is extremely low. This finding is additionally supported by the separate clustering of the four populations in the results of principal coordinate analysis. The useful information obtained in this study will offer insights to fine-tune conservation and fishery management measures in the future. 相似文献
6.
Qianhong Gu Huihui Wu Chuanjiang Zhou Xiaojuan Cao Weiming Wang Yanhong Wen Fuguang Luo 《Aquaculture Research》2020,51(4):1323-1335
The current genetic structure of a species is determined by both historical demographics and contemporary gene flow among populations. As an economically important snail in China, Bellamya has attracted much attention for its breeding and aquaculture and has provided a good study system for this theoretical structure. Our results showed that high genetic diversity occurred in most populations distributed in the Pearl River basin, except for the population in Nanning, Guangxi Zhuang Autonomous Region. A lack of distinct genealogical branches or geographic clades was found for the Bellamya complex across the Pearl River basin. Nevertheless, low but significant genetic structure and high differentiation were detected between Anshun (in Guizhou Province) and other geographic populations segregated by the Yunnan–Guizhou Plateau, suggesting that geographic barriers exist around this region, while this scenario was not applicable to the populations in Yuxi, Yunnan Province. The demographic history described a relatively stable pattern before the last glacial period, but the effective population sizes have drastically decreased since the late Pleistocene. The lack of genetic structure across the Pearl River basin is mainly attributed to a high level of gene flow by passive migration due to flooding and anthropogenic and animal translocation. The vicariance caused by the uplift of the Yunnan–Guizhou Plateau during the early Pleistocene likely contributed to the divergence of the plateau and plain sublineages in the Pearl River basin. A genetic diversity and phylogeography analysis are valuable to developing further guidance on breeding and conservation strategies for Bellamya germplasm resources. 相似文献
7.
Nian Xu Zhong Yang Yanfu Que Fang Shi Bin Zhu Meihua Xiong 《Journal of the World Aquaculture Society》2013,44(4):520-527
Chinese Sucker, Myxocyprinus asiaticus, is a valuable and endangered freshwater species in China. We investigated genetic diversity and differentiation of four M. asiaticus broodstock populations using 10 microsatellite loci. Three populations showed weak genetic differentiation among them. The other and the most distant population exhibited the lowest genetic diversity. It was inferred that wild M. asiaticus ancestry in the Yangtze River had sufficient gene flow among localities, while under the situation of population decline and fragmentation, restocking programs without genetic management might aggravate loss of genetic diversity and increase genetic differentiation. Maintenance of population connectivity among localities requires real attention in future restocking efforts. 相似文献
8.
An analysis of the effect of an extensive restocking programme on genetic differentiation and gene flow of the Atlantic salmon, Salmo solar L., in the River Shannon system in Ireland is presented, using allozyme electrophoresis to estimate population differentiation. The observed differentiation in the River Shannon is attributed to random genetic drift, caused by small effective population sizes in some of the tributaries, coupled with the confounding effect of extensive stocking of indigenous fish which were largely derived from a single tributary. The methods of analysis are assessed by applying numerical resampling techniques to determine confidence levels for each of the estimates. 相似文献
9.
黑龙江流域哲罗鲑的遗传结构分析 总被引：2，自引：0，他引：2
哲罗鲑(Hucho taimen)是中国土著濒危鱼类,仅黑龙江和新疆存在极小的繁殖群体,本研究利用17对微卫星分子标记对黑龙江流域哲罗鲑4个野生群体的遗传结构现状进行了分析。结果表明,黑龙江流域哲罗鲑野生群体具有中等水平的遗传多样性,其遗传多样性水平与种群数量具有相关性,呈逐年下降的趋势。遗传结构分析表明,群体间遗传分化显著,黑龙江流域哲罗鲑分化为2个遗传类型,HM遗传类型和WSL遗传类型,且WSL类型群体出现了进一步亚分化。黑龙江流域哲罗鲑各群体具有较小的有效群体,造成了各群体较大的近交压力。较小的有效群体主要是由于群体数量的变化及遗传瓶颈造成的。对黑龙江流域哲罗鲑野生群体近期和长期基因流检测发现,各群体间基因流不一致,迁入和迁出率不对称,表现为大群体向小群体流动。以上分析结果表明,环境的变迁、群体数量的下降等已造成黑龙江流域哲罗鲑遗传多样性的降低、遗传结构的分化,并导致了较小的有效群体数量,且对群体间基因流造成了障碍。本研究旨在为制定哲罗鲑的遗传保护措施提供基础科学依据。 相似文献
10.
基于线粒体D-loop基因的中国海三疣梭子蟹遗传多样性与遗传分化研究 总被引：1，自引：1，他引：0
为探明分布于中国四大海区的天然三疣梭子蟹群体遗传多样性与遗传分化状况,实验以大连(DL)、东营(DY)、连云港(LYG)、舟山(ZS)、湛江(ZJ)和漳州(ZZ)6个三疣梭子蟹地理群体为研究对象,采用线粒体控制区D-loop全基因序列为分子标记,对中国海三疣梭子蟹野生群体的遗传多样性及群体遗传结构进行了分析。结果发现,在用于分析的1 141 bp的D-loop全基因序列中共有185个变异位点,129个简约信息位点。60个个体中共计48个单倍型,单倍性多样性指数和核苷酸多样性指数显示中国沿海三疣梭子蟹群体具有较高的遗传多样性,而且三疣梭子蟹在过去没有出现很强的选择效应,群体大小稳定。6群体三疣梭子蟹遗传分化指数(FST)为0.189 7,将中国沿海三疣梭子蟹作为一个大群体来讲已产生了中度分化,群体分化时间推断为(19.68～26.05)万年。LYG分别和DY、ZJ、ZZ,以及ZJ和ZZ这4组之间无明显分化,基因流较大(Nem>5),而其他11个群组间已存在一定程度的分化。特别是ZS与其它5群体产生了高度的遗传分化,DL与其他4群体发生了中度分化。遗传距离与地理距离不存在显著的相关性,群体发生与扩散可能有更复杂的原因。 相似文献
11.
青海湖裸鲤繁殖群体遗传多样性的RAPD分析 总被引：19，自引：0，他引：19
采用随机扩增多态性DNA(RAPD)方法对青海湖裸鲤的3个洄游繁殖群体-黑马河(HM)、布哈河(BH)及沙柳河(SL)群体各30个个体的DNA多态性进行了分析。用13个引物在三个群体中共检测出85个位点,其中多态性位点68个。青海湖裸鲤群体总的DNA多态位点百分率为80．0％。数据分析结果显示：青海湖裸鲤3个群体总的Nei基因多样性为0．3395,Shannon遗传多样性信息指数为0．4861,存在着较为丰富的遗传多样性。青海湖裸鲤3个群体间平均遗传距离为0．0788,基因分化系数Gst为0．1070,表明3个繁殖群体间产生了一定程度的遗传分化,通过UPGMA方法进行聚类分析显示,HM群体和BH群体优先聚类,表示它们之间的基因交流程度要高于它们分别与SL群体之间的交流。 相似文献
12.
Genetic population structure of <Emphasis Type="Italic">Nibea albiflora</Emphasis> in Yellow Sea and East China Sea 总被引：1，自引：0，他引：1
Zhi Qiang Han Tian Xiang Gao Takashi Yanagimoto Yasunori Sakurai 《Fisheries Science》2008,74(3):544-552
ABSTRACT: The population genetic structure and level of gene flow of Nibea albiflora from the Yellow Sea and the East China Sea were examined with a 479-bp segment of a mtDNA control region. In total, 65 samples were collected from three locations and 37 haplotypes were obtained. Mean haplotype diversity and nucleotide diversity for the three populations ranged from 0.9130 ± 0.0308 (Zhoushan) to 0.9926 ± 0.0230 (Xiamen), and from 0.0073 ± 0.0043 (Qingdao) to 0.0099 ± 0.0057 (Xiamen). Analysis of molecular variance and pairwise F ST revealed little genetic structure between the Yellow Sea and the East China Sea in N. albiflora . But based on the exact test of differentiation, the null hypothesis that N. albiflora within the Yellow Sea and the East China Sea constitutes a panmictic mtDNA gene pool was rejected. This might be caused by the broad spawning areas but not by the Yangtze River outflow. Mismatch distribution revealed that N. albiflora has undergone population expansion, possibly before the last 85 000–170 000 years. The existence of high gene flow between stocks in the studied area was supported by our results. Annual migrations, larval drift in the ocean currents, and recent range expansion could be the reasons for little genetic structure in the studied area. 相似文献
13.
14.
淇河鲫与两野生鲫鱼群体遗传多样性的ISSR分析 总被引：2，自引：0，他引：2
应用ISSR技术对淇河鲫、金堤河鲫、沁河鲫3个群体进行遗传多样性研究。结果表明:(1)筛选8个引物共得到94个扩增位点,其中多态位点82个,多态位点百分率为87.23%。(2)Popgene分析结果,淇河鲫群体的遗传多样性水平相对较低,PPB=61.70%,H=0.2036,I=0.3085。(3)3个群体间的遗传分化系数GST=0.1303,基因流Nm=3.3359。表明3个群体的遗传分化尚未达到种群的分化水平。(4)金堤河鲫和沁河鲫群体间遗传距离较近,淇河鲫有一定的遗传分化,形成了较稳定的、独立的遗传结构。 相似文献
15.
Disentangling individual movement between populations from effective dispersal in the facultative anadromous Salmo trutta L. 下载免费PDF全文
下载免费PDF全文 Séverine Masson Olivier Lepais Aurélie Manicki Etienne Prévost Joelle Chat 《Ecology of Freshwater Fish》2018,27(1):323-338
Gathering information on both individual movement and gene flow is rarely possible when studying dispersal among populations in fish species. It is, however, possible to assess both at a reasonable cost in Salmo trutta L. on the Atlantic coast of Europe where the facultative anadromous species is composed of discrete populations of brown trout residents occupying distinct river systems, but exchanging phenotypically distinguishable sea trout migrants. We performed two kinds of genetic analyses using individual microsatellite genotypes: the stock identification of sea trout entering each corridor and the estimates of effective dispersal through each corridor. We observed that individual movement (nonlocal individuals of each source population ranging from 4% to 35% of the sea trout run) never translates into effective dispersal except in one of four migratory corridors examined. The likely origin of this uniquely detected gene flow event is discussed in the light of well‐documented migratory fish management actions undertaken in the past in the studied area. 相似文献
16.
水电开发造成的栖息地片段化可能导致鱼类群体间出现生殖隔离,对流域内重要经济和特有鱼类的群体遗传结构产生不利影响。为探究长江流域梯级水电开发可能对泉水鱼(Pseudogyrincheilus procheilus)群体产生的遗传影响,利用线粒体控制区对泉水鱼长江流域的乌江、金沙江、大渡河3个地理群体的遗传结构进行了分析。结果表明,乌江群体的遗传多样性最高,平均核苷酸差异(k)和核苷酸多样性指数(Pi)分别为4.893和0.00668;金沙江群体遗传多样性最小,k和Pi值分别为0.561和0.00077,大渡河群体遗传多样性与乌江群体相近。泉水鱼3个地理群体之间有显著的遗传分化。乌江群体和大渡河群体间的基因流大于金沙江群体和其他2个群体间的基因流,金沙江群体和其他2个群体间有着较远的遗传距离。Fu's Fs检验结果显示,3个地理群体的Fs值均为负值,核苷酸不配对分布均呈现明显的单峰型,揭示了各个泉水鱼群体均经历了明显的群体扩张。研究结果反映出泉水鱼遗传多样性较为丰富,金沙江群体和其他群体间显著的遗传差异可能是由于历史扩张而非自然选择造成的,泉水鱼存在区域化适应的地理群体,可预见梯级水电开发对其遗传结构的影响将十分有限。 相似文献
17.
The Japanese sea cucumber Apostichopus japonicus has a pelagic-lecithotrophic larva. Here, we clarify larval dispersal among Japanese sea cucumber populations by describing the levels of distinctiveness and gene flow among red and green variant populations of A. japonicus across Toyama Bay using 11 polymorphic microsatellite markers. Samples of Japanese sea cucumber populations were collected from three localities (Noto, Shinminato, and Uozu) around Toyama Bay. Geographically separated populations of red and green variants were determined to be genetically distinct, supported by phylogenetic analysis and the distinctiveness range values of pairwise multilocus estimates of F ST. Contemporary migration analyses indicated that the majority of estimated migration events occurred within A. japonicus populations comprised of only either red or green variants. In a historical gene flow analysis, two best-fit models (n-island and stepping stone models) showed circulation for the gene migration in Toyama Bay among red variant populations. Our results provide useful information on the genetic structure of Japanese sea cucumber populations and will be helpful for genetic conservation and fisheries management of sea cucumber populations in Toyama Bay. 相似文献
18.
利用14对微卫星引物,对采捕于辽宁葫芦岛、山东青岛、江苏连云港以及浙江舟山附近海域的梭鱼(Liza haematocheila)4个野生地理群体进行群体遗传多样性分析.结果显示,14对微卫星引物均能扩增出清晰的条带且具有一定的多态性,4个野生群体的多态性百分率分别为92.86％、92.87％、100.00％和85.71％.4个群体共扩增出61个等位基因,4个群体的等位基因数为3.786-4.000,有效等位基因数为2.673-2.899,观测杂合度为0.359-0.389,期望杂合度为0.503-0.561,多态信息含量为0.465-0.513,说明4个群体遗传多样性处于中等多态水平.运用SPSS软件对杂合度期望值进行Kruskal-Wallis检验,其结果(H=0.187,df=3,P=0.980)表明,4个群体间的遗传多样性差异无统计学意义(P＞0.05),各群体大部分微卫星位点偏离Hardy-Weinberg平衡(P＜0.05).另外,研究发现,葫芦岛和舟山均出现两个位点呈现杂合子过剩,其他两群体均出现3个位点呈现杂合子过剩(Fis＜0),表明近期可能出现过瓶颈效应.所有群体间遗传分化系数为0.148,基因流值为1.444,群体间出现中度遗传分化,群体间出现一定程度基因流.两群体间的遗传相似性系数为0.623-0.818,遗传距离为0.202-0.473,青岛和葫芦岛的遗传距离最近(0.202),而连云港和舟山的最远(0.473),这可能与梭鱼幼体的扩散能力及近海沿岸生态环境及群落结构有关.采用UPGMA法对4个群体进行聚类分析,结果显示,4个地理群体按其地理位置由北向南依次聚为一类. 相似文献
19.
Population genetic structure of common bottlenose dolphins (Tursiops truncatus) in the Adriatic Sea and contiguous regions: implications for international conservation 下载免费PDF全文
下载免费PDF全文 Stefania Gaspari Draško Holcer Peter Mackelworth Caterina Fortuna Alexandros Frantzis Tilen Genov Morgana Vighi Chiara Natali Nikolina Rako Elisa Banchi Guido Chelazzi Claudio Ciofi 《水产资源保护:海洋与淡水生态系统》2015,25(2):212-222
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20.
斑节对虾7个全同胞家系间亲缘关系的微卫星分析 总被引：1，自引：0，他引：1
为了斑节对虾（Penaeus monodon）后续育种工作的需要,研究了斑节对虾7个全同胞家系的亲缘关系。从95对微卫星引物中筛选出16对,16个微卫星位点共发现79个等位基因（A）。每个位点的A为2～10个,平均4.9375,有效等位基因（Ne）1.7575～5.3980,平均3.3878,平均杂合度观测值（Ho）0.6679,平均杂合度期望值（He）0.6698。平均多态信息含量（PIC）0.6110。7个家系总近交系数（FIT）0.0099,家系内近交系数（FIS）-0.3725,家系间基因分化系数（FST）0.2709。根据遗传距离采用UPGMA法对7个家系进行聚类,F2和F6家系之间的遗传距离最小聚为一类,与F7家系遗传距离最远。结果表明,家系间基因交流较低,遗传分化程度较高,且很少发生近交,F7家系可以优先考虑与其他家系进行杂交选育。 相似文献