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中国南海野生斑节对虾5个地理群体线粒体16S rRNA基因序列比较分析 总被引：2，自引：0，他引：2
对中国南海海域5个斑节对虾野生群体三亚群体(SY)、深圳群体(SZ)、阳江群体(YJ)、湛江群体(ZJ)、北海群体(BH)100个样品的16S rRNA 序列进行PCR扩增,并对扩增产物进行了测序.用CLUSTAL_X排序软件对测序所得的100个16S rRNA序列进行比对.通过ARLEQUIN软件对所得100个16S rRNA序列进行比较分析,共检测出28个变异位点,19种单倍型.三亚、深圳、阳江、湛江以及北海等5个野生群体的核苷酸多样性(π)依次分别为0.004 35,0.005 86,0.010 50,0.010 81,0.011 68.三亚、深圳、阳江、湛江以及北海等5个野生群体的单倍型多样性(H)依次分别为0.689 5, 0.521 1, 0.573 7, 0.600 0, 0.721 1.对5个野生群体的16S rRNA序列进行FST分析,结果表明湛江、北海群体分别与三亚、深圳两个群体有显著的遗传差异,其余群体之间的遗传差异不显著.对5个群体进行AMOVA分析结果表明,5个群体间存在显著性遗传差异.对5个群体构建分子系统树,结果表明,三亚和深圳群体之间的亲缘关系最近;北海、湛江群体与三亚、深圳群体的亲缘关系很远.实验表明,中国南海海域5个斑节对虾野生群体可以为斑节对虾的选择育种提供两个基础群体:一个是三亚、深圳野生原种基础群体;另一个是湛江和北海野生原种基础群体. 相似文献
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采用聚合酶链式反应(PCR)技术对海南三亚、深圳、湛江、北海4个斑节对虾群体共95个个体的延伸因子1-alpha 内含子序列进行了扩增，对扩增产物进行克隆转化，并将阳性克隆产物进行序列测定，最终获得了大小约216bp的可供分析的核苷酸序列。将获得的序列与从Genbank上下载的西太平洋、西印度洋序列进行比较分析。数据分析结果表明：北太平洋中国海域的基因多样性最低，西太平洋海域基因多样性水平最高；通过对遗传分化指数Fst的分析，发现西太平洋群体和西印度洋群体之间以及两者与北太平洋中国海域群体间遗传分化具有极显著性差异（P < 0.001）。UPGMA系统树显示，10个斑节对虾群体形成两大分支，一支由西太平洋群体和北太平洋中国海域群体组成，另一支由西印度洋群体单独组成；北太平洋中国海域群体中北海群体单独聚成一支。从序列差异的分析中得出，北太平洋中国海域群体与西印度洋群体之间的亲缘关系最远，与西太平洋群体之间的亲缘关系较近；中国海域内部各群体之间，北海群体与海南、深圳、湛江群体之间的亲缘关系较远，形成一个独特的地理种群。 相似文献
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采用聚合酶链式反应(PCR)技术对海南三亚野生斑节对虾(Penaeus monodon)20个个体的mtDNA 16S rRNA基因和控制区序列进行扩增,PCR产物经纯化后进行测序,得到16S rRNA基因的495 bp的核苷酸序列和控制区序列470 bp的核苷酸片段.用Clustal X软件对16S rRNA和控制区序列进行了比对,通过ARLEQUIN 2000软件对所得线粒体16S rRNA基因片段和控制区序列进行了比较分析.16S rRNA序列检测出17个多态位点,8种单倍型;控制区序列检测出100个多态位点,17种单倍型.该种群16S rRNA序列基因多样度(H)和碱基多样度(π)分别为0.700和0.0045;控制区序列的H和π分别为0.984和0.0480.研究结果表明16S rRNA序列不适应斑节对虾的种群遗传多样性分析;控制区序列适应斑节对虾种群遗传多样性研究. 相似文献
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海南三亚斑节对虾野生种群mtDNA 16S rRNA基因和控制区序列的多态性 总被引：1，自引：0，他引：1
采用聚合酶链式反应(PCR)技术对海南三亚野生斑节对虾(Penaeus monodon)20个个体的mtDNA 16S rRNA基因和控制区序列进行扩增,PCR产物经纯化后进行测序,得到16S rRNA基因的495 bp的核苷酸序列和控制区序列470 bp的核苷酸片段。用Clustal X软件对16S rRNA和控制区序列进行了比对,通过ARLEQUIN 2000软件对所得线粒体16S rRNA基因片段和控制区序列进行了比较分析。16S rRNA序列检测出17个多态位点,8种单倍型；控制区序列检测出100个多态位点,17种单倍型。该种群16S rRNA序列基因多样度(H)和碱基多样度(π)分别为0．700和0．0045；控制区序列的H和π分别为0．984和0．0480。研究结果表明：16S rRNA序列不适应斑节对虾的种群遗传多样性分析；控制区序列适应斑节对虾种群遗传多样性研究。 相似文献
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采用聚合酶链式反应(PCR)技术对北海、深圳和海南斑节对虾群体共60个个体的延伸因子1-alpha内含子序列进行了扩增,对扩增产物进行克隆转化,并将阳性克隆产物进行序列测定,最终获得了大小约200 bp的可供分析的核苷酸序列.数据分析结果表明:深圳群体的基因多样性为最高,北海群体基因多样性为最低;通过对遗传分化指数Fst的分析,发现北海群体、深圳群体和海南群体之间遗传分化不具有极显著性差异(P>0.05).UPGMA系统树显示,3个斑节对虾群体形成2大分支,1支由北海群体组成,另1支由海南群体和深圳群体组成.从序列差异的分析中得出,北海群体与海南、深圳群体之间的亲缘关系较远,海南群体与深圳群体之间的亲缘关系较近. 相似文献
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斑节对虾4个不同群体建立家系的生长及成活 总被引：1，自引：0，他引：1
以泰国（T）、非洲（A）和三亚（S）野生斑节对虾（Penaeusmonodon）群体,以及人工养殖斑节对虾群体（F）为父、母本建立家系。选择9个发育时间相近和较有代表性的家系,对其生长和饲料利用进行了为期30d的养殖试验。结果发现,大体上母本含三亚斑节对虾基因的家系成活率较高,其余较低,差异显著（P〈0．05）;母本含三亚斑节对虾基因的家系生长较差,其余较好（除T×T外）且差异极显著（P〈0．01）,A×A家系增重率是S×S的2倍;饵料系数没有显示明显的规律性。 相似文献
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Measuring and interpreting genetic structure to minimize the genetic risks of translocations 总被引：3，自引：0，他引：3
M S. Johnson 《Aquaculture Research》2000,31(1):133-143
Genetic subdivision of a species indicates the potential for local adaptation, and the genetic differences among populations are a key component of genetic diversity. Molecular genetic markers are generally used to assess the extent and pattern of subdivision. These traits provide an abundance of simple genetic markers, and they allow comparisons across studies. However, the connection of molecular genetic variation to local adaptation and, hence, to possible genetic problems of translocation, is weak. In the extreme case of no genetic subdivision, there is no reason to expect genetic problems with translocation. Where there is deep genetic structure, indicating substantial evolutionary independence of sets of populations, translocations may threaten basic components of genetic diversity. Between these extremes, however, predicting genetic problems of translocations is extremely difficult. The molecular markers used to measure genetic structure indicate where there has been opportunity for local adaptation, but they are not directly related to such adaptation. The relationship of the level of genetic divergence to genetic incompatibilities is very loose, although quantitative tests are scarce. However, studies of reproductive isolation between species illustrate the fundamental inadequacy of using measures of genetic divergence to predict interactions between populations. Although it is tempting to use simple measures as predictors, such use may provide a false sense of scientific rigour. There is no substitute for direct tests for variation in ecologically relevant traits and possible genetic incompatibilities among populations. 相似文献
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为了巩固经15年选育而成的团头鲂良种－浦江一号的成果，并建立纯系以供进一步研究和开发，1999年和2000年，先后对团头鲂选育系三龄鱼（F5）和二龄鱼（F6）进行了雌核发育（抑制第二次成熟分裂）研究。利用UV照射遗传失活的鲤鱼精子诱导，采用冷,凶制团头鲂第二体排出；探索了适合团头鲂二龄及三龄鱼卵的休克温度、起始时间和持续时间，结果发现：二龄鱼和三龄鱼诱导起始时间均在受精后3min效果最好，而在体温度和持续时间上稍有差异，其中三龄鱼在0－2℃冷休克处理30min、二龄鱼在4－6℃冷休克处理20min效果较好。2年期间，建立了源于选育系3尾雌亲鱼的3个雌核发育群体，共获得正常的雌核发鱼后代1000余尾。RAPD分析发现，选育系群体具有引物S8扩增的1100bp条带，而雌核发育群体具有引物S18扩增的860bp条带；雌核发育群体内遗传相似度显著高于选育系群体，其遗传距离仅为选育系群体内遗传距离的54％。 相似文献
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Sex change and the genetic structure of marine fish populations 总被引：1，自引：0，他引：1
The interaction between environmental forces and dispersal characteristics is largely responsible for the patterns of population structure in marine fish. Yet, crucial gaps in knowledge on life-histories and the relative contributions of numerous environmental factors still hinder a thorough understanding of marine population connectivity. One life-history trait so far overlooked by most fish population geneticists is sequential hermaphroditism, whereby individuals first mature as one sex and later in life reverse into the other sex. Population genetic theory predicts that sex-changing fish will present a higher potential for more spatially structured populations than gonochoristic species, as a result of their naturally skewed sex ratio, which is expected to reduce effective population size and hence increase genetic drift. We gathered published data on genetic population structure in marine fish, as summarized by the popular F ST index, and – after controlling for several potentially confounding factors – we tested the hypothesis that sex-changing species are more genetically structured than gonochoristic ones. Although we found no evidence to support the theoretical expectations, our results suggest new working hypotheses that can stimulate new research avenues at the intersection between physiology, genetics and fisheries science. 相似文献
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Erosion of the native genetic resources of brown trout in Spain 总被引：2，自引：2，他引：0
Abstract– We analyzed the introduction of hatchery-reared trout in the Riutort Creek, a small stream in the eastern Spanish Pyrennees. We used gene correlation matrices between individuals to analyze the fish coancestry in the Riutort Creek samples and in the hatchery stock. Hatchery fish disturbed the single ancestry in the native population of the creek, and were clearly detected with principal coordinate analysis of the gene correlation matrix. The amount of introgression produced by successful introductions was estimated from the principal coordinate analysis projections of the matrix of FST values between the putative native Riutort Creek population, the hatchery stock and the introgressed population. In only two years the amount of introgression rose to 10%, indicating that 5% of the native ancestry is lost each year as a result of the stocking program. Based on these results, we review the present understandings on the genetic impact of hatchery fish on indigenous Spanish brown trout populations. The stocking of these populations involves a non-native broodstock widespread through the Spanish hatcheries, but successful stockings appear to be limited to wild populations subjected to occasional releases in protected or unfished areas. Surprisingly, extensive stocking in fished areas result in a more limited genetic impact on the recipient native population. 相似文献
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伴随着中国水产养殖业的快速发展,原产美国的旧金山卤虫(Artemia franciscana)被引入至我国渤海湾地区.为研究旧金山卤虫被引入中国后其基因组遗传多样性改变情况,本研究利用COI线粒体分子标记,评估旧金山卤虫在非原生栖息地,即唐山曹妃甸南堡镇(渤海湾,河北省)定殖的旧金山卤虫的遗传多样性现状.研究分析发现:... 相似文献