首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 78 毫秒
1.
大黄鱼野生与养殖群体遗传结构的比较研究   总被引:3,自引:0,他引:3  
采用垂直板型不连续聚丙烯酰胺凝胶电泳技术对福建野生与养殖大黄鱼(Pseudosciaena crocea)4个群体(湄洲野生群体、宁德野生群体、宁德养殖群体、连江养殖群体)的遗传结构进行了比较研究。结果表明,4个大黄鱼群体的平均每位点有效等位基因数为1.1250~1.1293,多态位点百分数为12.50%~18.75%,观察杂合度为0.1250,期望杂合度为0.0636~0.0677。湄洲湾野生群体的遗传多样性高于养殖群体。4个大黄鱼群体间的遗传分化很低,4个大黄鱼群体间遗传距离在0.0000~0.0001,平均遗传距离为0.0005,遗传分化系数(Fst=0.0004)低,基因流(Nm=609.6667)大。  相似文献   

2.
皱纹盘鲍(Haliotis discus hannai Ino)是我国重要的经济海洋生物资源,以其营养价值高、味道鲜美而居海产八珍之首。由于资源的过度采捕、日益增加的养殖活动及海区环境污染等,可能会使皱纹盘鲍的遗传结构发生改变,继而影响到其适合度。为了种质资源的保护和可持续利用,同时也为了进一步完善皱纹盘鲍苗种繁育技术工艺,对我国近海皱纹盘鲍野生群体的遗传结构和变异研究是很有必要的。 等位基因酶电泳技术是研究海洋贝类遗传结构与变异的重要手段之一。目前世界上已有近百种海洋贝类的遗传结构和变异得到研究(张国范,1992;张国范等, 1993),皱纹盘鲍日本分布区不同群体遗传结构和变异研究也有相关报道(Fu jino et al., 1978)。本文作者采用等位基因酶电泳技术,随机选取了24个等位基因位点,对皱纹盘鲍我国分布区内四个野生群体的遗传结构和变异进行研究,为我国皱纹盘鲍种质资源研究和可持续利用提供基础数据。  相似文献   

3.
皱纹盘鲍野生与养殖群体遗传多样性的研究   总被引:12,自引:0,他引:12  
用随机扩增多态DNA(RAPD)技术,对山东长岛(CW)、辽宁大连(DW)两个野生群体和山东崆峒岛(KC)一个养殖群体的皱纹盘鲍遗传多样性进行了分析.结果表明,CW和DW群体间的遗传距离为0.170 3,CW和KC群体间的遗传距离为0.367 3,DW和KC群体间的遗传距离为0.347 7,显示野生群体与养殖群体之间的亲缘关系已发生了变化.CW,DW和KC三个群体的多态位点比例分别为49.22%、50.78%和43.75%;平均杂合度分别为0.350 6,0.340 8和0.307 9.与野生群体相比,养殖群体的多态位点比例和杂合度都有不同程度的降低.  相似文献   

4.
采用微卫星DNA分子标记方法对中国南部沿海多鳞鱚(Sillago sihama)广西北海、广东湛江、汕尾及海南三亚4个野生地理群体进行了遗传多样性及遗传分化等研究。结果表明:(1)用于研究的34对微卫星引物在4个群体中具有丰富的多态性,有效等位基因数介于1.71—20.46之间,多态信息含量PIC介于0.40—0.95之间。4个群体总的平均期望杂合度(He)为0.598,观测杂合度(Ho)为0.572,SY群体的杂合度最大(He=0.606,Ho=0.623),SW群体的最小(He=0.586,Ho=0.508)。(2)群体间F-统计量分析表明,群体遗传分化处于高度分化水平(Fst平均值为0.306);基于奈氏遗传距离(DA)构建的NJ和UPGMA聚类树均显示地理位置相邻的群体聚在一起。  相似文献   

5.
广东沿海杂色鲍养殖群体遗传多样性的微卫星分析   总被引:1,自引:0,他引:1       下载免费PDF全文
实验选取的7个杂色鲍(Haliotis diversicolor)养殖群体分别来自广东汕头、汕尾、惠东、湛江和徐闻,深圳野生驯养,利用7对微卫星引物对上述群体进行了遗传多样性和群体遗传结构的分析。结果显示:7个位点产生的等位基因数从7~13个不等,共检测到68个等位基因,平均每个位点的等位基因数为9.71个。有效等位基因数的范围为3.8~8.1,平均观测杂合度范围为0.422~0.906,平均期望杂合度范围为0.748~0.917。7个群体的多态信息含量变化范围为0.657~0.883,PIC值均在0.500以上,表现为高度多态性。与两个野生驯养的养殖群体相比,其他5个养殖群体均存在不同程度的遗传多样性降低。AMOVA分析显示,4.79%的遗传变异来自于群体之间,95.21%的变异来自于群体内的个体之间。研究表明,广东沿岸的杂色鲍具有较高的遗传多样性水平,7个群体之间呈现一定的遗传分化。  相似文献   

6.
为评估养殖过程对漠斑牙鲆遗传结构的影响, 本研究利用微卫星标记对漠斑牙鲆(Paralichthys lethostigma)山东胶南养殖群体(子一代)和江苏南通养殖群体(子三代)的遗传结构进行分析比较, 结果表明所使用的14 对引物中, 11 对引物在所选取的群体中具有多态性, 两个群体中共检测出了70 个等位基因(42 个有效等位基因), 总群体的平均观察杂合度(Ho)和期望杂合度(He)分别为0.36 和0.60。两个群体的Shannon’s 遗传多样性指数分别为1.18 和1.07, Nei’s 遗传多样性指数分别为0. 56 和0.51, 表明山东胶南群体的遗传多样性显著高于江苏南通养殖群体。两个养殖群体间的两群体间的遗传分化系数Fst 平均为0.1246, 遗传距离(Ds)为0.171, 遗传相似度为0.8432, 表明两个群体中度分化。由此可以得出, 在中国随着漠斑牙鲆累代养殖的开展, 其遗传多样性下降显著, 遗传结构已经出现了显著分化。因此, 在将来的繁育过程中应制定合理的育苗规划以维持漠斑牙鲆的多样性水平并保障产业可持续发展。  相似文献   

7.
为了解我国养殖九孔鲍Haliotis diversicolor supertexta的遗传多样性和遗传结构,用RAPD技术对我国福建、广东和海南的九孔鲍5个养殖群体进行了遗传变异分析。12条引物共扩增出141条清晰稳定的条带,大小范围为0.2—2.4kb,其中多态性条带97条,多态位点比例为68.8%。基因多样性介于0.210±0.193与0.247±0.187之间,平均为0.224,各群体间没有显著差异。聚类分析表明,福建东山群体和广东惠来群体亲缘关系最近,聚为一支;深圳、湛江和三亚群体亲缘关系较近,聚为另一支。群体间遗传距离介于0.062与0.135之间,福建东山群体与广东惠来群体间遗传距离最小,惠来群体与深圳群体间遗传距离最大。群体间FST值介于0.176与0.326之间,随机组合检验表明,群体间遗传分化已经达到显著水平,但东山和惠来与深圳、湛江和三亚2组之间遗传分化不显著。较高的遗传多样性水平表明近年来九孔鲍大规模死亡事件可能与遗传多样性并无直接相关,而较高的遗传多样性有利于遗传选育。不同地方群体间的显著分化表明,各地方群体应分别作为单独的"管理单元(management unit)"进行遗传资源管理,群体之间的移植应严格监管。  相似文献   

8.
采用微卫星DNA分子标记方法对中国南部沿海多鳞鱚(Sillago sihama)广西北海、广东湛江、汕尾及海南三亚4个野生地理群体进行了遗传多样性及遗传分化等研究。结果表明:(1)用于研究的34对微卫星引物在4个群体中具有丰富的多态性,有效等位基因数介于1.71—20.46之间,多态信息含量PIC介于0.40—0.95之间。4个群体总的平均期望杂合度(He)为0.598,观测杂合度(Ho)为0.572,SY群体的杂合度最大(He=0.606,Ho=0.623),SW群体的最小(He=0.586,Ho=0.508)。(2)群体间F-统计量分析表明,群体遗传分化处于高度分化水平(Fst平均值为0.306);基于奈氏遗传距离(DA)构建的NJ和UPGMA聚类树均显示地理位置相邻的群体聚在一起。  相似文献   

9.
盘鲍和皱纹盘鲍等位酶的生化遗传分析   总被引:6,自引:0,他引:6  
应用聚丙烯酰胺凝胶电泳技术,对盘鲍(Haliotis discus discus)和皱纹盘鲍(Haliotis discus hannai)的养殖群体进行了10种等位酶的电泳检测和谱带遗传分析。确定了盘鲍的18个等位酶位点及21个等位基因,单态位点有15个;仅有3个位点是多态的,它们是Sod-1,Est-3,Mdh-1(P0.99标准),多态位点的百分数为16.67%,这些多态位点分析到2个等位基因。确定了皱纹盘鲍的18个等位酶位点及20个等位基因,单态位点有16个;仅有2个位点是多态的,它们是Sod-1,Est-3(P0.99标准),多态位点的百分数为11.11%,这些多态位点中也分析到2个等位基因。盘鲍和皱纹盘鲍在所有位点中共享大多数常见等位基因,因此在生化遗传上它们非常相似。该研究揭示了盘鲍和皱纹盘鲍养殖群体等位酶位点及其等位基因带谱的变异式样,为盘鲍和皱纹盘鲍的遗传结构及遗传育种的研究提供了一批等位酶位点及其等位基因的参考图谱。  相似文献   

10.
虾夷扇贝(Patinopecten (Mizuhopecten) yessoensis)于1982年从日本引进,在中国已经成为一个很重要的产业.本研究利用微卫星标记,对獐子岛海域2个养殖群体虾夷扇贝(大耗岛、褡裢岛),1个日本野生群体遗传多样性进行了评估,并对2个养殖群体的群体内繁育和群体间杂交后代进行了遗传和生长检测.结果表明:养殖群体与日本野生群体相比,其遗传多样性没有显著降低,养殖群体遗传多样性较高,养殖状况暂时良好.TL群体和DH群体遗传距离很近, DH、TL群体和RB群体的遗传距离远大于 TL群体和 DH群体间的遗传距离.说明2个养殖虾夷扇贝群体遗传分化较小.分别对4个子代群体的壳长、壳高在幼苗培育第1、5、10、15、20、100、190天进行测量,结果表明生长性状差异不显著.4个子代群体的遗传多样性差异也不显著,说明养殖群体的遗传背景不清楚,种质资源混交较严重.本研究结果反映了我国虾夷扇贝种质资源评估状况,并为虾夷扇贝的健康养殖提供基础数据.  相似文献   

11.
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.
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   

14.
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   

17.
Coastal inundation associated with extreme sea levels is the main factor which leads to the loss of life and property whenever a severe tropical cyclonic storm hits the Indian coasts. The Andhra and Orissa coasts are most vulnerable for coastal inundation due to extreme rise in sea levels associated with tropical cyclones. Loss of life may be minimized if extreme sea levels and associated coastal flooding is predicted well in advance. Keeping this in view, location specific coastal inundation models are developed and applied for the Andhra and Orissa coasts of India. Several numerical experiments are carried out using the data of past severe cyclones that struck these regions. The simulated inland inundation distances are found to be in general agreement with the reported flooding.  相似文献   

18.
19.
Grain size and water content in box-core sediments from the Clarion-Clipperton fracture zone (C-C zone) in the northeast equatorial Pacific were analyzed in detail to understand the downcore variations across a hiatus between Quaternary and Tertiary layers. Grain-size distributions in the topmost core sediments show two modes: a coarse mode (peaked at 50 μm) and a fine mode (at 2-25 μm). The coarse mode disappears gradually with depth accompanied by the dissolution of siliceous fossil tests, whereas the fine mode coarsens due to the formation of authigenic minerals. Water content increases abruptly across a color boundary between an upper pale brown layer and a lower dark brown layer that is the hiatus between Quaternary and Tertiary layers. Abundant smectites and microvoid molds, which are created by the prolonged fossil dissolution in the underlying sediment, are attributed for the abrupt downcore variation of water content. Overall variations in grain size and water content in the topmost core sediments in the western C-C zone are possibly constrained by the dissolution of biogenic siliceous fossils. Variations in geotechnical properties related to these changes must be considered in the design of nodule collectors.  相似文献   

20.
This article concerns an interrelation between the sea levels and the western boundary flow near a tectonic boundary in a local zone in the Northwestern Pacific. In this zone, sea level variations at stations located on the coast facing the Pacific are studied to find the interrelation between variations of the Kurosio flow as an index of the distance of the flow axis off a specific coast. The result is discussed after data processing of the monthly means of the sea levels, and a notice is taken of variations caused by active crustal upheavals during a seismic event, a local earthquake.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号