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1.
4种养殖扇贝的群体遗传多样性及特异性AFLP标记研究 总被引：29，自引：2，他引：27
应用AFLP技术对我国4种主要养殖扇贝进行了遗传分析.虾夷扇贝、海湾扇贝、华贵栉孔扇贝、栉孔扇贝4种养殖扇贝群体中,种内遗传相似度依次分别为0.841 5,0.786 3,0.719 0和0.673 1,香侬氏指数分别为43.52,58.87,80.16和92.83,栉孔扇贝和华贵栉孔扇贝的遗传多样性水平明显高于海湾扇贝和虾夷扇贝;AFLP标记共享位点分布表明,在4种扇贝中栉孔扇贝与华贵栉孔扇贝之间的共享位点最多,同时4种扇贝的种间遗传相似度也以栉孔扇贝和华贵栉孔扇贝之间为最高(0.769 5),海湾扇贝和虾夷扇贝之间为最低(0.662 6),揭示所研究的几种扇贝中栉孔扇贝和华贵栉孔扇贝的遗传关系最近(遗传距离为0.262 1);找到了21个种内特异性AFLP标记和种间共享标记,可用于种质鉴定和分子辅助分类. 相似文献
2.
栉孔扇贝不同种群的遗传结构及其杂种优势 总被引：15，自引：4，他引：15
采用来自韩国野生的栉孔扇贝和中国养殖的栉孔扇贝以及发病区存活个体作为亲本 ,构建韩国野生×韩国野生、韩国野生×中国养殖、韩国野生×中国养殖发病区存活个体以及中国养殖×中国养殖共 4个交配组合 ,通过对F1 代个体壳宽、壳高和体重的测量 ,比较不同群体的生长情况。同时采用RAPD技术对F1 代不同群体的遗传结构进行比较 ,研究群体内的遗传变异与杂种优势的关系。结果表明 ,杂交后代具有明显的生长优势 ,说明栉孔扇贝种内不同种群之间存在杂种优势。韩国野生种群和中国养殖群体以及发病区存活群体的遗传距离分别为 0 0 3 6 6和 0 0 0 5 7,以上 4个F1 代群体的平均杂合度的理论值分别为 0 2 83、0 2 6 7、0 2 6 8和 0 2 6 6 ;多态位点比例分别为 0 76 5、0 76 0、0 76 0、0 73 5。表明栉孔扇贝不同地理种群之间存在遗传分化 ,其杂种优势与群体的遗传多样性相关 相似文献
3.
为了解栉孔扇贝(Chlamys farreri)、虾夷扇贝(Patinopecten yessoensis)及其杂交子代(F1)的种群遗传多样性和遗传结构,对3个群体的线粒体COI和Cytb基因的部分序列进行了扩增和分析。经比对分别获得781bp和725bp核苷酸片段,74个样本共检测到47个单倍型;F1群体的单倍型数、单倍型多样性指数、核苷酸多样性及平均核苷酸差异数都是最高的,而双亲的较低;F1和栉孔扇贝间的遗传距离最小,其次为栉孔扇贝和虾夷扇贝群体之间,F1和虾夷扇贝群体之间的遗传距离最大;F1和栉孔扇贝之间的遗传分化系数较小而两者间的基因流比较大,F1和栉孔扇贝与虾夷扇贝之间的遗传分化系数较大而基因流较小,说明栉孔扇贝和虾夷扇贝群体群体很早就发生了遗传分化;采用UPGMA法和简化的中介网络法构建的系统树表明,3个群体的所有个体被分为2个族群,栉孔扇贝和F1交叉聚为一类,虾夷扇贝独自聚为一类,2个分支间没有交叉;使用特异性引物分别对3个群体进行PCR扩增检验,结果栉孔扇贝的特异引物能在杂交子代中扩增,而虾夷扇贝的特异引物不能在子代中扩增出条带,说明栉孔扇贝和虾夷扇贝杂交,其子代的线粒体遗传模式为严格的母系遗传。本研究结果表明杂种优势的形成与线粒体遗传多样性的变化有关。 相似文献
4.
采用单一自由度独立比较的方法,研究了两个栉-华杂交组合HCH(栉孔扇贝长岛群体×华贵栉孔扇贝)和HJH(栉孔扇贝胶南群体×华贵栉孔扇贝)以及栉孔扇贝种内交配组合ZZ的胚胎发生及幼虫生长发育过程。结果表明,栉孔扇贝和华贵栉孔扇贝的种间杂交F1在生长和发育的两个环节上是不一致的,在涉及器官及其功能形成的发育环节上,杂交表现负效应;而在涉及形态变化和增大的生长环节上,杂交表现正效应,存在杂种优势现象。两个杂交组合中,HJH综合效果较好,授精22h平均孵化率达到95.8%,与ZZ基本接近;30日龄平均变态率达61.5%,明显好于组合HCH的42.0%;8日龄幼虫平均大小达143.4μm×123.2μm,表现出更强的生长优势。这些结果为全面评价栉孔扇贝与华贵栉孔扇贝杂交体系应用价值和选配优良杂交组合提供了理论依据。 相似文献
5.
几何形态学(morphometrics)是基于笛卡尔地标点的统计分析方法,主要运用广义普鲁克分析(GPA)、薄板样条分析(TPS)、主成分分析(PCA)、典型变量分析(CVA)等方法,定量的对形态变化进行识别,结果更为客观。本研究运用几何形态学方法对8种常见扇贝(栉孔扇贝Azumapecten farreri、虾夷盘扇贝Mizuhopecten yessoensis、海湾扇贝Argopecten irradians、平濑掌扇贝Volachlamys hirasei、北海道扇贝Swiftopecten swiftii、荣套扇贝Gloripallium pallium、华贵类栉孔扇贝Mimachlamys nobilis、美丽环扇贝Annachlamys striatula)间形态关系进行研究,运用界标点和半界标点对扇贝的壳盘和壳耳进行数字化标点,利用PCA、CVA、TPS方法,获得8种扇贝的形态差异并进一步分析,建立系统发育树。PCA和CVA分析结果表明可以通过几何形态测量学分析方法将8种扇贝基于形态差异进行有效区分。此外,结合TPS的分析结果,发现壳耳和壳盘在扇贝中具有种间规律性差异。通过其形态分异进行表型聚类,从结果可知:美丽环扇贝、虾夷盘扇贝和海湾扇贝距离较近,壳型有共同的特征:扇贝壳盘较椭圆,壳耳相对较小;荣套扇贝和华贵类栉孔扇贝距离较近,壳型有共同的特征:扇贝壳盘更扁平,前耳相对较大;北海道扇贝、平濑掌扇贝和栉孔扇贝与其他种类没有交集。在聚类过程中,华贵类栉孔扇贝和荣套扇贝有交集,10个标本混淆,其他标本均成功聚类,正确率为95.5%。 相似文献
6.
栉孔扇贝♀×华贵栉孔扇贝♂受精及早期胚胎发育过程的细胞学荧光显微观察 总被引：4，自引：0，他引：4
为探讨贝类杂交优势 ,利用HOECHST3 3 2 5 8对已固定样品进行染色的方法 ,连续观察了栉孔扇贝♀×华贵栉孔扇贝♂受精的细胞生物学过程 ,初步证明了这 2种远缘扇贝种类之间进行杂交的可行性。结果表明 ,栉孔扇贝的成熟未受精卵子处于第一次减数分裂中前期 ,部分来自华贵栉孔扇贝的异源精子可顺利进入卵子并激发后者完成 2次减数分裂 ,排出第一及第二极体。成熟的雌雄原核形成后完成融合过程 ,形成合子核 ,受精过程结束。大部分杂交受精卵及杂种早期胚胎可以正常发育 ,但其发育进程较种内近交对照组有明显的差别 ,具体表现在延缓性和不同步性 2个方面。 相似文献
7.
栉孔扇贝大规模死亡问题的对策与应急措施 总被引：32，自引：5，他引：27
在对山东沿海栉孔扇贝大规模死亡原因进行分析的基础上,从理论和技术上提出了解决栉孔扇贝死亡问题的对策和应急措施,包括坚持可寺续发展,产业结构调整,加强科技意识,实施“外延稀养”战略等对策和改良种质,增强抗逆能力,切实合理降低养殖密度,研究死亡原因和防病措施,开展多元化养殖,建立浅海持续养殖示范区,保护栉孔扇贝自然种群和建立扇贝良种场等应急措施。 相似文献
8.
本文采用DAPI染色荧光显微方法连续观察了栉孔扇贝♀×海湾扇贝♂的受精细胞学过程,发现海湾扇贝精子可以正常入卵,并能完成后续的发育过程获得杂交后代。同时进行栉孔扇贝♀×海湾扇贝♂杂交组及栉孔扇贝、海湾扇贝自交组3组实验,对各组的受精率、卵裂率、D形幼虫孵化率、幼虫生长速度、幼虫存活率进行统计分析,实验结果表明:杂交组的受精率为92.77%,卵裂率为81.46%,D形幼虫孵化率为51.23%,杂交组幼虫在培育到第7天时全部死亡,栉孔扇贝和海湾扇贝自交组的幼虫可正常发育到眼点幼虫,杂交组幼虫在其存活阶段的生长和2自交组无显著性差异,但成活率差异显著。 相似文献
9.
栉孔扇贝×虾夷扇贝的杂交技术 总被引：7，自引：0，他引：7
以栉孔扇贝与虾夷扇贝为实验材料,进行了两者之间自交和栉孔扇贝♀×虾夷扇贝♂和虾夷扇贝♀×栉孔扇贝♂的杂交的实验。实验结果表明:两者的杂交是可行的,在幼虫阶段表现出一定的生长优势,幼虫成活率间没有差异,但在幼虫附着变态方面,杂交组低于自交组,两者之间有明显的差异。然后以具有生长优势的栉孔扇贝♀×虾夷扇贝♂组进行了生产性育苗实验,取得明显的经济效益。 相似文献
10.
应用MSAP技术研究扇贝全基因组DNA甲基化水平 总被引：1，自引：0，他引：1
DNA甲基化作为真核生物基因组重要的表观遗传学修饰,对生物体基因的表达有重要的调控作用。为获得扇贝基因组DNA甲基化修饰水平及模式等表观遗传学信息,以栉孔扇贝(Chlamys farreri)、海湾扇贝(Argopecten irradians)、虾夷扇贝(Mizuhopecten yessoensis)以及本课题组培育的"海大金贝"为材料,建立了甲基化敏感扩增多态性方法(Methylation-sensitive amplified polymorphism,MSAP)的反应体系,利用该方法对其基因组DNA CCGG区域的甲基化水平进行分析。结果表明,本研究筛选得到的引物组合可用于贝类DNA甲基化的研究,在栉孔扇贝、海湾扇贝、普通虾夷扇贝和"海大金贝"的甲基化比例分别为32.08%、25.99%、32.88%和34.97%。几种扇贝基因组CCGG序列中,胞嘧啶的全甲基化率要高于半甲基化率,推测扇贝基因组中主要的甲基化模式是CpG型。通过对"海大金贝"和普通虾夷扇贝闭壳肌甲基化谱进行比较,筛查得到46个差异位点,这些位点可能参与"海大金贝"闭壳肌积累类胡萝卜素的调控。 相似文献
11.
Arne Schnack-Friedrichsen Angela M. Davis Jim D. Bennell Dei G. Huws 《Marine Georesources & Geotechnology》2001,19(4):221-243
The interdependence between the seismo-acoustic properties of a marine sediment and its geotechnical/physical parameters has been known for many years, and it has been postulated that this should allow the extraction of geotechnical information from seismic data. Though in the literature many correlations have been published for the surficial layer, there is a lack of information for greater sediment depths. In this article, a desktop study on a synthetic seafloor model illustrates how the application of published near-surface prediction equations to subsurface sediments (up to several tens of meters burial depth) can lead to spurious predictions. To test this further, acoustic and geotechnical properties were measured on a number of sediment core samples, some of which were subjected to loading in acoustically-equipped consolidation cells (oedometers) to simulate greater burial depth conditions. For low effective pressures (representing small burial depths extending to around 10 meters subsurface), the general applicability of established relationships was confirmed: the prediction of porosity, bulk density, and mean grain size from acoustic velocity and impedance appears generally possible for the investigated sedimentary environments. As effective pressure increases through, the observed relationships deviate more and more from the established ones for the near-surface area. For the samples tested in this study, in some instances increasing pressure even resulted in decreasing velocities. There are several possible explanations for this abnormal behavior, including the presence of gas, overconsolidation, or bimodal grain size distribution. The results indicate that an appropriate depth correction must be introduced into the published prediction equations in order to obtain reliable estimates of physical sediment properties for greater subsurface depths. 相似文献
12.
Shigehisa Nakamura 《Marine Geodesy》2000,23(1):55-61
Specific properties of the interannual sea level variations and annual tides in the Northwestern Pacific were studied. Several tide stations were monitored. The monthly mean sea level for the year of 1995 was analyzed at each tide station. A seismic event in 1995, some tectonic activity around the subject area, and the Kuroshio (the oceanic western boundary current) may possibly contaminate results which would have occurred from the astronomical annual tide alone. 相似文献
13.
The effect of different fixation and storage protocols on the flow cytometric (FCM) simultaneous analysis of bacterioplankton and phytoplankton in coastal seawater samples (Mediterranean coastal lagoons) was investigated. FCM measurements (cell number, fluorescence and scatter characteristics) were obtained through DAPI staining. Three fixatives [glutaraldehyde (GA), formaldehyde (FA) and paraformaldehyde (PFA)] and two storage (3 months duration) methods (5 °C and −196 °C) were tested. Two dominant populations were detected in studied samples: bacteria and eukaryotic picophytoplankton. Adding fixatives (2% final concentration) appears necessary to obtain FCM exhaustive counts of all the bacteria and phytoplanktonic cells. This was related to the permeation effect of fixatives which allowed a better DAPI staining of the cells. Maximum fluorescence, i.e. optimal staining of the cells was obtained with FA or PFA, and significant lower fluorescences with GA. Fixed samples stored at 5 °C induced rapid cell loss. Only storage in liquid nitrogen of samples fixed with FA or PFA, allows mid-term (≥4 months) preservation of bacteria or picophytoplankton cell numbers, and limited evolution of DAPI-induced fluorescence and scatter characteristics. 相似文献
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15.
《海洋学报(英文版)》2014,(9):F0003-F0003
<正>Acta Oceanologica Sinica(AOS)is a comprehensive academic journal edited by the Editorial Committee of Acta Oceanologica Sinica and is designed to provide a forum for important research papers of the marine scientific community which reflect the information on a worldwide basis.The journal publishes scholarly papers on marine science and technology,including physics,chemistry,biology, 相似文献
16.
The relationship between the flux of exotic benthic foraminiferal tests (i.e. tests which are supplied from open-sea sources alone) in a tidal inlet and that of bulk sediment was analysed, which can be expressed as two first-order linear equations. According to this relationship, in order to determine net sediment transport directions in the entrance, the test concentration in surficial sediments of the tidal basin can be compared against a ‘ critical level ’. The critical level is determined for the conditions that no net transport of bulk sediment is present within the entrance. If the observed concentration (averaged over the tidal basin) is higher than the simulated critical level, then the net sediment transport is directed to landward. This method is applied to the analysis of net sand transport at Christchurch Harbour, a tidal inlet system located in southern England. In this investigation, concentrations of exotic foraminiferal tests in the surficial sediments of the tidal basin and ebb tidal delta area were obtained from the analysis of sea-bed sediment samples. A series of probable critical levels were calculated based upon the data sets with regard to: (1) sediment discharge from the rivers; (2) magnitude of sediment discharge within the entrance during the ebb; (3) the test concentration outside the harbour; (4) the thickness of the moving layer; and (5) two parameters associated with dispersive processes. The results show that the concentration in the tidal basin sediment is higher than a number of simulated critical concentrations for representative cases. Consequently, the high level of the concentration of exotic benthic foraminiferal tests within the harbour should be explained as a result of landward net transport of sands within the entrance. 相似文献
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18.
Rahul Sharma 《Marine Georesources & Geotechnology》2000,18(3):237-250
Observations on seafloor features from subbottom profiling and seabed photography data show that the undisturbed and natural conditions before the benthic disturbance undergo a substantial change after operation of the disturber. The effects can be seen in the form of deep trenches and grooves, formed by the action of the sleds and the pumping of the sediment along its path, as well as sediment piles on either side of the track. Biological traces such as fecal coils, casts, tubes, burrows, and trails get obliterated in the areas of disturbance and resedimentation. The smooth, uniform nature of the seafloor observed in predisturbance phase shows microtopographic changes in and around the disturbed area as a result of sediment excavation and resettlement. Vertical mixing as well as lateral transport of sediment alter the geological, biological, physical, and chemical conditions on the seafloor, which need to be monitored over time to assess the process and the time taken for restoration of environmental conditions. 相似文献
19.
Vance P. Vicente 《Marine Ecology》1989,10(2):179-191
Abstract. Long-term changes in the distributional patterns of commercial sponges ( Spongia spp. and Hippospongia spp.) within the West Indian Region indicates that: 1) commercial sponges had a widespread distribution throughout the whole West Indian Region and were ubiquitous in very shallow water until about the first half of the present century; 2) they were fished commercially not only in the traditional northern Caribbean sites (Florida, Gulf of Mexico, Bahamas) but also in the Greater ( e. g. , Hispaniola, Jamaica) and Lesser Antilles; and 3) they became extinct throughout most of the Lesser Antilles ( e. g. , Puerto Rico, Vieques, St. Thomas) sometime during the first half of this century. Mortalities of spongiids within the Antilles were found to differ from other marine mortalities in that: 1) species disappeared from a large region; 2) species vanished from different habitats and depths; and 3) natural populations never recovered. Species richness patterns suggest that commercial sponge genera ( Spongia and Hippospongia ) evolved under slightly cooler elimatic conditions than those found at present, and that these extinctions occurred as a direct or indirect effect of positive thermal anomalies in sea surface and atmospheric temperatures between 1900–1950. The concept that species diversity is stable on a regional scale is questioned. 相似文献
20.
The behaviour of an axially pre-loaded cylindrical member of an offshore structure, hit by a supply ship, has been investigated. The effects of axial pre-loading on the dynamic properties of members, the extent of damage and propagation of dynamic instability in the tubular members have also been investigated. Numerical models have been validated using available experimental data from the literature although these are mostly static with no pre-loading. Axial pre-loading was found to change the dynamic characteristics of some cylindrical members quite dramatically while it had no significant effect on others. The study examined whether there was any change in the behaviour between local and global modes when the loading was dynamic rather than static. The effect of damping on the dynamic instability of axially pre-loaded tubes under lateral dynamic loads was also studied. It was observed that for some geometries the quasi-static response can be used to define the boundary between bounded and unbounded dynamic responses. The main contribution of this study, compared with previous investigations reported in the literature, is that both pre-loading and dynamic effects have been included. 相似文献