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中国对虾黄、渤海沿岸地理群的RAPD分析 总被引：43，自引：1，他引：42
采用随机扩增多态DNA(random amplified polymorphic DNA,简称RAPD)技术,对中国对虾的黄、渤海地理群的32个个体遗传多样性进行了检测,使用OPI系列的20个10bp的寡核苷酸随机引物,对每个个体的基因组DNA进行扩增,结果为:17个引物获得了谱带清晰且重复性好的产物,扩增片段的分子量在2000～2000bp之间,共检测106个位点,其中多态位点数为39个,占36.8%;平均遗传距离为0.0941+0.0206,有67个标记(占63.2%)在整个群体的32个个体间表观稳定的一致性. 相似文献
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基于RAPD的SCAR分子标记技术鉴定虎纹蛙及引进种 总被引：2，自引：0，他引：2
为了对引进种泰国虎纹蛙加强种质监测,本文对泰国虎纹蛙和中国虎纹蛙进行了SCAR标记研究。在对2种蛙随机扩增多态DNA(RAPD)标记研究的基础上,选用随机引物OPP5和OPZ19对2种蛙进行扩增,将2个特异性扩增片段OPP5-471bp和OPZ19-512bp回收、克隆和测序,并根据序列信息设计两对SCAR引物SP5和SZ19。利用两对SCAR引物对2种蛙基因组DNA扩增的结果显示:SP5显示了其特异性,在对中国虎纹蛙的扩增中出现了单一SP5-388bp特异片段,而在泰国虎纹蛙中没有扩增产物;SZ19在对2种虎纹蛙的扩增中出均出现了单一条带,但片段大小不同,在中国虎纹蛙中为SZ19-456bp,在泰国虎纹蛙中为SZ19-497bp。3个分子标记都可作为基于RAPD成功转化后的SCAR分子标记对2种虎纹蛙进行鉴定。 相似文献
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采用扩增片段长度多态性(AFLP)技术分析了香鱼(Plecoglossus altivelis)养殖群体的遗传多样性,并筛选性别特异性分子标记。结果表明,15对选扩引物组合共扩增到889个位点,其中多态性位点380个,多态率为42.74%;群体Nei氏遗传多样性指数为0.1454,Shannon氏指数I为0.2174。香鱼养殖群体的遗传多样性较丰富,处于中等偏上水平。仅引物组合E-ATG/M-CTG扩增到1条雄性特异性条带,长度为139bp。以该雄性特异性AFLP条带的DNA序列为模板,设计1对特异的PCR引物并在10尾已知性别的香鱼(雌雄各5尾)中扩增检验,结果显示5尾雄鱼均可扩增到目的条带而5尾雌鱼均无扩增。表明该序列是雄性特异性分子标记,可用于鉴别香鱼的遗传性别,并为香鱼的性别决定机制和性别控制研究奠定基础。 相似文献
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采用磁珠富集法及利用生物素标记的(CA)15寡核苷酸探针从波纹唇鱼(Cheilinus undulatus)基因组DNA Bsp143Ⅰ酶切位点的400~1000 bp片段中筛选CA/GT微卫星位点。洗脱的杂交片段克隆到PMD18-T载体上构建富集微卫星基因组文库后,通过PCR筛选出阳性克隆进行测序。在120条序列中有88条序列包含有重复次数不少于5次的微卫星位点,阳性序列比例达到73.33%。其中完美型(perfect)类型微卫星最多的重复次数为26次。在88条非冗长序列中,共有28条(31.82%)微卫星重复序列两端有侧翼序列能够进行引物设计。用波纹唇鱼3个个体的混合基因进行引物筛选,其中的24对具有清晰的扩增条带。将筛选的24对引物对波纹唇鱼1个群体的39个个体进行遗传多样性分析,其中4对引物扩增产物为单态,20对扩增产物呈多态性;20对扩增多态的引物在39个个体中扩增出等位基因数为2~12,平均有效等位基因数为3.5。该波纹唇鱼群体的PIC、Ho、He的平均值分别为0.0782、0.8513、0.5667。这20个微卫星位点适于波纹唇鱼群体遗传结构的研究分析。 相似文献
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大菱鲆(Scophthalmus maximus)生长性状相关的微卫星标记筛选 总被引：4，自引：2，他引：2
采用分群分离分析法,以同一批受精卵孵化的同池养殖大菱鲆生长性状发生分离的群体为材料,进行微卫星DNA遗传分析,以揭示影响大菱鲆生长发育速度方面的遗传信息。30个多态性微卫星位点对生长高值组(F组)和生长低值组(S组)各10个样本建立的DNA混合池进行扩增时,在两池间出现了7个差异片段。通过对两组大菱鲆个体PCR扩增出的差异条带进行统计,分析微卫星位点与大菱鲆生长性状的相关性。结果表明,有1个微卫星位点(SmaC10)在355bp的等位基因片段与大菱鲆生长性状存在一定的负相关性;有4个微卫星位点(SmaC02、SmaC06、SmaC09、B11-I12/6/3)分别在258bp、182bp、226bp、175bp的等位基因片段与大菱鲆生长性状存在正相关性,其中位点Smac09在226bp的等位基因片段与生长性状的正相关性极显著,相关系数达到0.354。位点SmaC09所扩增出的等位基因片段可作为具有良好生长特性人工选育群体的分子标记,指导大菱鲆的辅助育种。 相似文献
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丹江口水库赤眼鳟(Squaliobarbus curriculus)遗传多样性的RAPD和ISSR分析 总被引：1，自引：0，他引：1
利用RAPD和ISSR两种分子标记技术,分析了丹江口水库野生赤眼鳟30个个体的遗传多样性。用11个RAPD引物对其基因组DNA进行扩增,共获得101个重复性好且谱带清晰的扩增位点,片段大小在100—3000bp之间,其中多态性位点63个,多态位点比例为62.38%;个体间遗传距离在0.1049—0.3417之间,平均为0.1742。用10个ISSR引物共检测到88个位点,其中多态性位点61个,多态位点比例为69.32%;个体间遗传距离在0.1088—0.3847之间,平均为0.1907。结果显示,丹江口水库野生赤眼鳟群体的多态位点比例和平均遗传距离均较大,说明其有较高的遗传多样性。 相似文献
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皱纹盘鲍(Haliotis discus hannai Ino)和杂色鲍(Haliotis diversicolor Reeve)遗传多样性的RAPD研究 总被引：13，自引：0，他引：13 
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下载免费PDF全文 于 2 0 0 1年 8月— 2 0 0 2年 7月 ,选用 2 0条能产生清晰可重复扩增产物的随机引物 ,对皱纹盘鲍 (HaliotisdiscushannaiIno)、杂色鲍 (HaliotisdiversicolorReeve)进行了RAPD分析 ,共检测到 2 1 3个位点 ,在群体之间和个体之间都存在差异。利用PopGen32软件计算各群体扩增位点的多态性比例、群体遗传杂和度和群体间的遗传距离 ,多态比例分别为 43.66%、5 3 0 5 % ,2个群体的平均杂合度为 0 .1 5 5 7、0 .1 686。结果表明皱纹盘鲍与杂色鲍的亲缘关系较远。 相似文献
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凡纳滨对虾引进亲虾及其子一代的遗传多样性研究 总被引：1，自引：0，他引：1
采用Operon公司的16个引物对两个凡纳滨对虾(Litopenaeus vannamei)引进亲本群体及其子一代对虾的基因组DNA多态性进行了检测。第一个亲虾群体对16个引物共获得78个位点,其中多态位点数为48个,占61.54%;其子代对虾共获得89个位点,其中多态位点数为50个,占56.18%。第二个亲虾群体对16个引物共获得97个位点,其中多态位点数为49个,占50.52%,其子代对虾共获得93个位点,多态位点数为28个,占30.11%。单个引物获得的标记数为1～8个。第一个亲本群体及其子代个体间的平均遗传距离分别是0.1959±0.0392和0.1435±0.0268;第二个亲本群体及其子代个体间的平均遗传距离分别为0.0922±0.0189和0.0621±0.0148。两个亲本群体间的遗传距离为0.6546±0.0794,两个子代群体间的遗传距离为0.7087±0.0656。在OPF-09、OPZ-11两个引物的扩增结果中,发现两个亲本群体及其子代有差异标记。 相似文献
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Chandralata Raghukumar G. Sheelu P. A. Loka Bharathi Shanta Nair C. Mohandass 《Marine Georesources & Geotechnology》2001,19(1):1-16
In order to assess the impact of deep-sea mining on the in situ benthic life, we measured the microbial standing stock and concentration of organic nutrients in the deep-sea sediments of the Central Indian Ocean Basin in the Indian pioneer area. Sediments were collected using box core and grab samples during September 1996. The total bacterial numbers ranged from 10 10 -10 11 cells per g -1 dry weight sediment. There was a marginal decrease in the number of bacteria from surface to 30 cm depth, though the subsurface section registered a higher number than did the surface. The highest numbers were encountered at depths of 4-8 cm. The retrievable number of bacteria were two orders less in comparison with the direct total counts of bacteria. An almost homogeneous distribution of bacteria, total organic carbon, living biomass, and lipids throughout the depth of cores indicates active microbial and benthic processes in the deep sea sediments. On the other hand, a uniform distribution of total counts of bacteria, carbohydrates, and total organic carbon in all the cores indicates their stable nature and suggests that they can serve as useful parameters for long-term monitoring of the area after the benthic disturbance. Further studies on temporal variability in this region would not only verify the observed norms of distribution of these variables but would also help to understand restabilization processes after the simulated benthic disturbance. 相似文献
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海上大直径钢管桩打桩过程中,桩周土体受到强烈扰动而发生强度弱化,掌握桩周土体强度弱化规律对于准确预测打桩过程、保证工程安全具有重要意义。为研究土体强度弱化规律,开展了环剪试验模拟打桩对桩周土体的扰动,测试土体强度随剪切速率的变化规律,建立了描述土体强度弱化规律的拟合公式,引入到打桩分析软件中。研究结果表明：土体的强度折减程度不仅与土体本身的性质有关还受到土体的埋深和剪切速率的影响,埋深越深土体强度折减程度越低,剪切速率越高土体强度折减越高,在打桩分析中可采用这里推荐的线性折减方法来模拟不同深度处土体强度的折减规律。 相似文献
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Geoacoustic Inversion via Genetic Algorithm and Its Application to Manganese Sediment Identification
An acoustic inversion method using a wide-band signal and two near field receivers is proposed and applied to multiple layered seabed models including a manganese sediment. The inversion problem can be formulated into a probabilistic model comprised of signals, a forward model, and additive noise. The forward model simulates wide-band signals, such as chirp signals, and is chosen to be the source-waveletconvolution plane wave modeling method. The wavelet matching technique, using weighted least-squares fitting, estimates the sediment sound-speed and thickness on which determination of the possible numerical ranges for a priori uniform distribution is based. The genetic algorithm is applied to a global optimization problem to find a maximum a posteriori solution for determined a priori search space. Here the object function is defined by an L 2 norm of the difference between measured and modeled signals. Not only the marginal pdf but also its statistics are calculated by numerical evaluation of integrals using the samples selected during importance sampling process of the genetic algorithm. 相似文献
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Derek V. Ellis 《Marine Georesources & Geotechnology》2001,19(1):51-63
This article reviews information recently available from existing marine and coastal mining for responses to environmental issues affecting marine mining at different depths. It is particularly but not exclusively concerned with those issues affecting seabed biodiversity impact and recovery. Much information has been gathered in the past 10 years from shallow mining operations for construction aggregate, diamonds, and gold, from coastal mines discharging tailings to shallow and deep water, and from experimental deep mining tests. The responses to issues identified are summarized in a series of eight tables intended to facilitate site-specific consideration. Since impacts can spread widely in the surface mixing layer SML, and can affect the biologically productive euphotic zone, the main issues considered arise from the depth of mining relative to the SML of the sea. Where mining is below the SML, the issue is whether it is environmentally better to bring the extraction products to the surface vessel for processing (and waste discharge), or to process the extraction products as much as possible on the seabed. Responses to the issues need to be sitespecific, and dependent on adequate preoperational environmental impact and recovery prediction. For deep tailings disposal from a surface vessel, there are four important environmental unknowns: (1) the possible growth of "marine snow" (bacterial flocs) utilizing the enormous quantities of fine tailings particles (hundreds or thousands of metric tons per day) as nuclei for growth, (2) the possibility that local keystone plankton and nekton species may migrate diurnally down to and beyond the depth of deep discharge and hence be subjected to tailings impact at depth, (3) the burrow-up capability of deep benthos and their ability to survive high rates of tailings deposition, and (4) the pattern and rate of dispersion of a tailings density current through the deep water column from discharge point to seabed. Actions to obtain relevant information in general and site-specifically are suggested. 相似文献
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G. Parthiban 《Marine Georesources & Geotechnology》2000,18(3):223-235
Particle fluxes were measured 7 m above the sea bottom during the predisturbance, disturbance, and postdisturbance periods by using time series sediment traps attached to seven deep-sea moorings deployed in the INDEX experiment site in the Central Indian Basin. The predisturbance particle fluxes varied between 22.3 to 55.1 mg m -2 day -1 . Increased and variable particle fluxes were recorded by the sediment traps during the disturbance period. The increase observed was 0.5 to 4 times more than the background predisturbance fluxes. The increases in particle fluxes (~4 times) recorded by the sediment trap located in the southwestern direction (DMS-1) were the greatest, which could be the result of preferential movement of resuspended particles generated during the deep-sea benthic disturbance along the general current direction prevailing in this area during the experimental period. Also, the traps located closer to the disturbance area recorded greater fluxes than did the traps far away, across the Deep Sea Sediment Resuspension System path. This variability in recorded particle fluxes by the traps around the disturbance area clearly indicates that physical characteristics such as grain size and density of the resuspended particles produced during the disturbance had an important effect on particle movement. The postdisturbance measurements during ~5 days showed a reduction in particle fluxes of ~50%, indicating rapid particle settlement. 相似文献
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Phylogenetic diversity and phenotypic characterization of cultivable bacterioplankton isolated from polar oceans 总被引：1，自引：0，他引：1
A set of 27 marine planktonic bacteria isolated from the polar regions was characterized by 16S rDNA sequencing and physiological and biochemical testing. More than half of these bacteria were positive for caseinase, gelatinase and 13-glucosidase, and could utilize glucose, maltose or malic acid as carbon source for cell growth. Twelve isolates expressed nitrate reduction activities. Except for one antarctic isolate BSwlO175 belonging to Actinobacteria phylum, these isolates were classified as γ-Proteobacteria, suggesting that γ-Proteobacteria dominated in cultivable marine bacterioplankton at both poles. Genus Pseudoalteromonas was the predominant group in the Chukchi Sea and the Bering Sea, and genus ShewaneUa dominated in cultivable bacterioplankton in the Prydz Bay. With sequence similarities above 97%, genus Psychrobacter was found at both poles. These 27 isolates were psychrotolerant, and significant 16S rDNA sequence similarities were found not only between arctic and antarctic marine bacteria （ 〉 99% ）, but also between polar marine bacteria and bacteria from other aquatic environments （ ≥ 98.8% ）, including temperate ocean, deep sea, pond and lake, suggesting that in the polar oceans less temperature-sensitive bacteria may be cosmopolitan and have a bipolar, even global, distribution at the species level. 相似文献
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The advanced piston corer (APC) has been used by the Ocean Drilling Program since 1985 for recovering soft sediments from the ocean floor. The pullout force measured on extracting the core barrel from the sediment is shown to correlate with the average shear strength of the sediment core measured in the ship's laboratory. A simple rule of thumb is derived relating the shear strength of the sediment to the pullout force. Multiple APC holes at individual sites allow the consistency of the pullout measurements to be assessed. The effects of different operational procedures during APC coring are also explored. Although generally applicable, the correlation between pullout force and laboratory measurements of shear strength breaks down for some APC holes, possibly because of the disturbance of some sediment types during the APC coring process. A better understanding of the physical process of APC coring, and its effect on the properties of the sediment both inside and immediately outside the core barrel, would indicate what confidence can be put on the measurement of pullout force as a way of evaluating the in situ shear strength of deep sea sediments. 相似文献
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Oedometer tests have been carried out on 70 undisturbed surficial clays (at approximately 250 mm below the mudline), mostly collected by free-fall corers from sites widely scattered throughout the deep-sea North Atlantic. Acoustic measurements were also made, initially on contiguous samples and ultimately on the same sample using a geophysically instrumented oedometer which also collected electrical resistivity data. Apart from those quiescent areas below the carbonate compensation depth, such as north of the West Indies where very fine clays exist, most of the samples are silty clays whose geotechnical-geophysical properties are dependent on the type of clay minerals present (and their ability to take in moisture), the sand-size fraction, and the quantity of carbonate present. Thus the pure clays have high compressibilities which decrease on the addition of coarse particles, while the converse is true for the acoustic parameters, these increasing with the sand fraction. Using the notion of the intrinsic compression line for all samples, and comparison to it of the measured compression curves, it is clear that, contrary to some previously held ideas, most deep-sea clays are normally consolidated; the addition of carbonate has the effect of creating an open, stronger sediment skeleton. Interestingly, where information is available, the variation with depth of a sample's acoustic velocity follows the void ratio pressure relationship of the compression curve. This allows the construction of an in-situ sediment compression curve using the in-situ geophysical observations. 相似文献