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1.
《中国草地学报》2017,(3)
用7条ISSR引物研究我国18个野生斑茅居群的遗传多样性和遗传结构,结果表明:(1)7条ISSR引物共扩增出69条清晰条带,多态性条带59条,占83%;观测等位基因数、有效等位基因数、Shannon指数和Nei’s基因多样性指数等指标均显示我国斑茅遗传多样性丰富。(2)斑茅居群内的变异大于居群间,由此推测斑茅是异花授粉的地理广布种。(3)聚类分析发现,斑茅居群间存在明显的遗传分化,遗传距离和地理距离的Mantel检测发现两者的相关性弱。(4)斑茅各居群间的基因流较小,地理环境的隔离及生境异质影响到斑茅变异在居群内和居群间的分布、聚类结果及斑茅的居群结构。 相似文献
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四川青衣江、岷江流域鹅观草遗传多样性的溶蛋白分析 总被引：4，自引：0，他引：4
用酸性聚丙烯酰胺凝胶电泳(A-PAGE)技术对采自青衣江流域和岷江流域的97份鹅观草材料的种子醇溶蛋白进行了分析。在对四川青衣江、岷江流域鹅观草居群的醇溶蛋白分析中,鹅观草材料醇溶蛋白带谱存在显著差异,共出现27个条带,其中多态性条带25条,占总条带数的92.59%;鹅观草的遗传相似性与其地理分布较为一致,表现在:1)青衣江、岷江流域鹅观草总遗传多样性指数为0.345 1,其中青衣江流域鹅观草遗传多样性指数为0.340 0,岷江流域鹅观草遗传多样性指数为0.310 0,表明青衣江流域鹅观草比岷江流域存在更为丰富的遗传变异,多样性指数更高;但流域间遗传分化系数仅为0.04,表明两江流域间遗传分化较小;各居群间遗传变异系数达0.326,表明总遗传多样性的32.6%来自居群间。2)在同一流域不同居群也存在遗传分化,其中青衣江流域各居群(除峨眉山居群分散聚在各居群外)能聚在一起;而岷江流域各居群在成都平原区段互相渗透,但能以上、中、下游区段聚开;青衣江流域各居群中以蒙山居群遗传多样性指数最高,达0.339 8,洪雅居群最低,仅0.094 7;岷江流域上游居群多样性指数最高,为0.301 7,而下游以乐山居群遗传多样性指数最低,为0.131 7。3)同一居群内鹅观草存在遗传变异,两江流域以蒙山居群变异最大,多样性指数最高。对居群遗传多样性的研究还表明,鹅观草垂直分布的遗传多样性高于水平分布;在成都平原居群由于生境片断化,导致岷江流域鹅观草生境片断化后小居群遗传分化增加,而整个成都平原“大居群”遗传多样性降低。 相似文献
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青藏高原东南缘老芒麦自然居群遗传多样性的SRAP和SSR分析 总被引：3，自引：0，他引：3
基于SRAP和SSR分子标记分析了青藏高原东南缘8个老芒麦自然居群遗传变异及群体遗传结构,获得下述结果:1)16对SRAP引物在90个单株中共扩增出384条可统计条带,其中多态性条带334条,占86.98%;16个SSR位点共检测出等位变异221个,平均每个位点13.8个,其中具有多态性的位点数192个,占86.88%。2)2种分子标记检测到老芒麦居群水平的基因多样性(He)分别为0.1092和0.1296,而物种水平的基因多样性达0.2434和0.3732。3)基于2种标记的Nei氏遗传分化指数Gst(0.5525和0.5158)表明老芒麦居群出现了较大程度的遗传分化,居群间的基因流非常有限,分别为0.4050和0.4694,老芒麦的遗传变异主要分布在居群间,居群内变异相对较小,Shannon多样性指数和分子方差变异(AMOVA)分析显示了相似的结果。4)基于聚类分析结果表明各居群间存在较为明显的地理分化,8个居群分化为采集地范围内的南、北和中部3个分支。通过对老芒麦遗传多样性和遗传结构的分析提出了对该物种遗传多样性的保护策略。 相似文献
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应用SSR分子标记,对河南省15个居群共288份狗牙根材料进行遗传多样性及群体遗传结构分析,结果表明,10对引物共扩增出173条条带,其中163条为多态性条带,多态性条带百分率为94.29%,表明河南省狗牙根具有丰富的多态性。15个居群间的遗传分化系数为0.3857,即发生在居群间的遗传变异达到38.57%,大部分的遗传变异发生在居群内部,居群间基因流为0.7964,居群之间存在一定程度的基因交流。不同居群间遗传一致度的变化范围是0.746~0.964,平均为0.767。15个居群间的UPGMA聚类分析结果表明居群间没有完全按照地理来源进行聚类,遗传距离和地理距离矩阵之间的Mantel检验结果表明狗牙根居群间的遗传距离与地理距离之间无相关性。288份狗牙根材料之间的遗传距离为0.0173~0.5205,平均为0.3113,UPGMA聚类结果将所有材料分为3组。基于Structure软件的群体遗传结构分析结果表明,可将288份狗牙根材料分为2个亚群和一个混合型群体,与288份材料的UPGMA聚类结果基本一致,由此可判断两个亚群的遗传背景单一,混合型群体存在一定的种质基因渗透,遗传背景较为复杂。 相似文献
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《中国草地学报》2016,(4)
选择地理来源相近和生境相似的野生斑茅、割手密(甘蔗属)、蔗茅(蔗茅属)材料各10份,以5份苞子草(菅属)为外类群,利用SRAP和ISSR分子标记研究斑茅与其他两个近缘种的亲缘关系,结果表明:4个物种间遗传多样性水平非常高,SRAP和ISSR分子标记的平均多态性位点百分率分别为98.0%和97.6%,且斑茅和割手密种内具有高的遗传多样性水平;在共有带上,斑茅与割手密和蔗茅SRAP标记分别为4条和13条,ISSR标记均为7条,说明不同标记在共有带上呈现不一样的规律,但SRAP标记斑茅与蔗茅呈现较多的共有条带数;聚类分析表明,各材料明显按照物种进行聚类,相同物种的材料全部聚在一起,在物种间斑茅优先与蔗茅聚为一类,而后与割手密聚在一起形成"甘蔗属复合体",而苞子草单独聚为一类;研究支持将斑茅划离甘蔗属,划入蔗茅属。 相似文献
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本研究利用SCoT标记对洞庭湖地区9个野生南荻居群的遗传多样性和遗传结构进行分析。结果表明:27条SCoT引物共扩增出429条清晰的带,其中多态性带为394条,多态性条带比率为91.39%,平均每条引物扩增多态性条数是14.60条,多态性信息含量(PIC)为0.206~0.688,平均为0.394;该地区南荻遗传多样性丰富,遗传多样性指标水平较高(PPB=91.39%、H=0.3266、I=0.4911);其野生居群具有一定程度的遗传分化(Gst=0.1141),遗传变异主要存在于居群内;居群间的基因流(Nm)为3.88;根据非加权配对类平均法(UPGMA)聚类分析,将南荻9个野生居群分为三类,同一流域的居群聚为一类;材料间的遗传距离与地理距离不存在相关性。 相似文献
7.
本研究采用ISSR分子标记技术分析了甘肃省4个地区(合作、碌曲、阿万仓和阿孜)钝裂银莲花的11个居群的遗传多样性水平和遗传结构。结果表明,13个引物共扩增出701条带,其中392条具有多态性,多态位点百分率为55.92%。在物种水平上,Shannon多样性指数(I)为0.372,Nei基因多样性指数(H)为0.250;Nei的基因分化系数Gst和AMOVA分析表明钝裂银莲花居群遗传分化大部分存在于居群间。在居群水平上,I为0.183,H为0.114,可见钝裂银莲花居群具有较高的遗传多样性。依据Nei的遗传距离对不同居群进行UPGMA聚类,聚类结果为合作居群为一类,碌曲和阿万仓居群为一类,阿孜为一类。居群遗传多样性与环境因子间的相关性分析表明,遗传多样性水平与海拔、含水量、有效磷和经纬度之间没有相关性,而与降水量之间显著负相关。 相似文献
8.
采用SRAP方法分析,对采自中国四川岷江、青衣江和沱江流域的29份野生苞子草(Themeda caudata(Nees) A.Camus)材料进行遗传多样性分析。结果表明:用20对SRAP引物组合共得到158条可统计条带,其中多态性条带98条,平均每对引物扩增出4.9条多态带,多态性条带比率为62.03%。材料间的遗传相似系数GS值变化范围为0.6899～0.9430,平均GS值为0.8755,这些结果表明供试野生苞子草具有丰富的遗传多样性;对所有材料进行聚类分析,在GS值为0.78的水平上,可聚成2大类;在GS值为0.81的水平上,第2大类Ⅱ可聚为2亚类;在GS值为0.83的水平上,第2亚类Ⅱ又可聚为3子类,大部分来自相同或相似生态地理环境的材料聚为一类;基于Shannon多样性指数估计6个苞子草生态地理类群内和类群间的遗传分化,发现类群内的遗传变异占总变异的50.77%,而类群间的遗传变异占总变异的49.23%;对各生态地理类群基于Nei氏无偏估计的遗传一致度聚类分析说明,各生态地理类群间的遗传分化与其所处的生态地理环境具有一定的相关性。 相似文献
9.
青藏高原老芒麦种质基于SRAP标记的遗传多样性研究 总被引：7，自引：1，他引：6
采用SRAP分子标记技术,对采自青藏高原的52份老芒麦材料进行遗传多样性分析,结果表明,1)用16对随机引物组合共扩增出318条清晰可辨的条带,其中多态性条带275条,占86.48%,材料间的遗传相似系数(GS)范围为0.506 4～0.958 6,平均值为0.792 1,物种水平上的Nei氏遗传多样性为0.227 0,这些结果说明供试老芒麦具有较为丰富的遗传多样性;2)对所有材料的聚类分析发现,在GS=0.80的水平上,供试材料可聚为5类,大部分来自相同或相似生态地理环境的材料聚为一类,表明供试材料的聚类和其生态地理环境间有一定的相关性;3)对5个老芒麦地理类群基于Shannon-Weaver指数的遗传分化估算发现,类群内遗传变异占总变异的65.29%;而类群间遗传变异占总变异的34.71%;4)对各生态地理类群基于Nei氏无偏估计的遗传一致度聚类分析表明,各生态地理类群间的遗传分化与其所处的生态地理环境具有一定的相关性。 相似文献
10.
24份桑树品种资源基于SRAP分子标记的亲缘关系分析 总被引：1，自引：0，他引：1
《蚕业科学》2015,(2)
应用SRAP分子标记引物对24份桑树品种资源的基因组DNA进行PCR,检测其遗传多样性,分析品种间的亲缘关系。15对SRAP引物扩增产生126条谱带,平均每对引物产生8.4条谱带,其中多态性条带共99条,多态性比率为78.57%,说明24个桑树品种间具有丰富的遗传多样性。基于品种间遗传相似系数的UPGMA聚类图和基于品种的SRAP标记类型的主成分分析中,蒙桑种(Morus mongolica Schneid.)的品种吉蒙桑、白桑种(Morus alba L.)的品种垂枝桑和山桑种(Morus bombycis Koidz.)的品种昌农山桑单独聚类,其他来自白桑种、广东桑种(Morus atropurpurea Roxb.)、鲁桑种(Morus multicaulis Perr.)的栽培品种分为3组;白桑种种内各品种间的遗传变异较小,而广东桑种、鲁桑种种内各品种间的遗传变异相对较大;广东桑3个品种间的遗传背景差异较大;鲁桑栽培品种农桑12号与其父本桐乡青的遗传相似度高,而与母本北区一号的差异显著,并且鲁桑种内各品种间未能完全聚类,品种间的亲缘关系与地理分布位置的距离相关。筛选的15对SRAP引物能够有效地检测供试桑树品种的遗传多样性,揭示品种间的亲缘关系。 相似文献
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In this paper we discuss the use of genetic engineering in livestock production. We examine the main two different aspects of genetic engineering: cloning and transgenesis. After commenting what has been expected from both techniques in livestock production in the last 25 years, the practical difficulties for implementing cloning and transgenesis are examined. Apart from technical difficulties, problems derived from the detection of genetically superior animals and evaluation of the clones and the transgenic animals make these techniques less interesting than they appear to be. Most of the observed variability of the economically interesting traits is not genetic, genetic evaluation needs a large number of animals and cloning success will represent a serious loss of genetic variability and the loss of the flexibility needed for markets in constant evolution. There is a risk in transgenic animals of production of new intermediate biochemical products that may be toxic, allergenic or carcinogenic. The benefits produced by transgenic animals hitherto hardly justify this risk. The expectations that genetic engineering produced 25 years ago should be re-examined, considering the risks and the high investment required. 相似文献
14.
利用12对微卫星引物对毛乌素沙地油蒿种群的遗传分化、基因流进行分析,采用Nei’s指数和Shannon指数估算3个不同类型沙地种群的遗传多样性,计算种群相似系数和遗传距离,利用遗传距离构建系统树。结果表明:(1)种群遗传多样性分析显示,油蒿种群多态位点百分率为100%,说明油蒿种群基因组ISSR具有较高的多样性。(2)在遗传距离为6.0处可将184个样株大致分为三类,涵盖了135个样株,占采样总量的73.34%。结合样地定位记录,聚类结果与样株空间分布具有一致性,即可分为流动沙地、固定沙地、半固定沙地油蒿种群。(3)流动沙地与固定、半固定沙地油蒿种群间的基因流较小,分别为0.7929和0.6848,半固定与固定沙地油蒿种群间存在着较高的基因流,为6.2930。半固定与固定沙地种群间的遗传一致度较高,为93.77%;流动沙地种群Shannon指数低。 相似文献
15.
E. Thorn Hellsten A. Nsholm H. Jorjani E. Strandberg J. Philipsson 《Livestock Science》2009,121(2-3):207-214
The objective of this study was threefold: 1) To survey the use and impact of foreign stallions in the Swedish Warmblood (SWB) breed 2) To investigate the impact of including genetic groups in the genetic evaluation of the SWB and 3) To estimate the impact of incomplete pedigree information on the estimated breeding values (EBVs) for stallions. Data consisted of 189,330 horses of which 50,907 had performance information. Studbook of origin was determined for stallions with at least 5 progeny tested in Sweden. Those 757 stallions had together 116,505 progeny registered in the SWB. Genetic groups were formed according to preliminary analyses of the genetic levels in dressage and show jumping of the different populations. During the first studied period, comprising horses born before 1980, about 80% of the foals were sired by Swedish born stallions, whereas these only sired 40% of the horses born 1990–2003. In this period Holstein stallions had sired 21% of the foals and Dutch stallions (KWPN) 10%. The proportion of mares covered by foreign stallions increased after the early 1980s to about 80% in 2006. Some of the foreign populations, e.g., Holstein, Selle Francais and KWPN, have significantly affected the show jumping performance level of the SWB breed in the past although the deviation from SWB stallions has become smaller over time. Regarding dressage, no particular foreign population has consistently shown such an impact on the performance although Oldenburg stallions seem to be influential lately. The pedigree completeness (PEC values) of the horses included amounted on average to 0.845 for horses with performance data and to 0.907 for stallions with at least 15 progeny. Foreign stallions had an average PEC value of 0.858. When simulating no pedigree information available for foreign stallions, the EBVs of these stallions changed on average by 19–22 index units, which equals about one genetic standard deviation. Thus, keeping complete and correct pedigree registers is crucial for the assessment of reliable EBVs of SWB horses. Including genetic groups in the genetic evaluation of the SWB resulted in hardly any re-ranking of horses. Correlations between EBVs were about 0.99. Inclusion of genetic groups caused larger standard errors of the EBVs. Furthermore, as the pedigrees on average have great depth, and partially also because Warmblood sport horses have become a mix of many different populations, it was not recommended to include genetic groups in the model for future routine genetic evaluations of SWB. 相似文献
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Two Chinese domestic yak populations representing the Plateau type and the Huanhu Alpine type were analysed with 12 bovine microsatellite primers. All primer pairs functioned in the yak genome and polymorphism was found at all loci. The allele size ranges and frequencies of the two yak populations were similar and there was considerable overlap with the allele size ranges observed in cattle. Data for European cattle breeds was obtained from the Cattle Diversity Database(CaDBase)to interpret the heterozygosity and genetic distance estimates in yak populations. Heterozygosity estimated for the two yak populations was comparable to that of European cattle while Nei's Genetic Distance DA between the two yak populations was less than distances between the most closely related German cattle breeds. Bovine microsatellite primers proved to be a valuable tool for characterization of yak populations. 相似文献
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基于SSR分子标记的药用黄芪遗传多样性与遗传结构分析 总被引：1，自引：0，他引：1
为了能更好的了解药用黄芪（Astragali Radix）遗传多样性及遗传结构,本试验利用10对SSR引物对来自17个产地共380个样本的蒙古黄芪、膜荚黄芪进行遗传多样性及结构分析,结果显示药用黄芪具有较高程度的遗传多样性水平（I=2.112,H=0.781）,其中蒙古黄芪遗传多样性水平（I=2.241,H=0.804）要高于膜荚黄芪（I=1.982,H=0.757）,且两种黄芪的遗传变异主要发生在居群内;UPGMA聚类分析及STRUCTURE居群遗传结构分析可将其分为3组,即膜荚黄芪为单独一组,蒙古黄芪分为两组,其中来自山西产区的大部分居群分为一组,来自内蒙产区及部分山西产区的居群分为另一组。本研究结果对药用黄芪种质资源的有效利用、遗传多样性的保护、育种及开发优质黄芪种质资源提供一定的理论基础。 相似文献
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A review of genetic parameter estimates for wool, growth, meat and reproduction traits in sheep 总被引：3，自引：0，他引：3
Genetic parameters for a range of sheep production traits have been reviewed from estimates published over the last decade. Weighted means and standard errors of estimates of direct and maternal heritability, common environmental effects and the correlation between direct and maternal effects are presented for various growth, carcass and meat, wool, reproduction, disease resistance and feed intake traits. Weighted means and confidence intervals for the genetic and phenotypic correlations between these traits are also presented. A random effects model that incorporated between and within study variance components was used to obtain the weighted means and variances. The weighted mean heritability estimates for the major wool traits (clean fleece weight, fibre diameter and staple length) and all the growth traits were based on more than 20 independent estimates, with the other wool traits based on more than 10 independent estimates. The mean heritability estimates for the carcass and meat traits were based on very few estimates except for fat (27) and muscle depth (11) in live animals. There were more than 10 independent estimates of heritability for most reproduction traits and for worm resistance, but few estimates for other sheep disease traits or feed intake. The mean genetic and phenotypic correlations were based on considerably smaller numbers of independent estimates. There were a reasonable number of estimates of genetic correlations among most of the wool and growth traits, although there were few estimates for the wool quality traits and among the reproduction traits. Estimates of genetic correlations between the groups of different production traits were very sparse. The mean genetic correlations generally had wide confidence intervals reflecting the large variation between estimates and relatively small data sets (number of sires) used. More accurate estimates of genetic parameters and in particular correlations between economically important traits are required for accurate genetic evaluation and development of breeding objectives. 相似文献
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Ubbink GJ Van den Ingh TS Yuzbasiyan-Gurkan V Teske E Van de Broek J Rothuizen J 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2000,14(2):172-176
Inherited copper toxicosis in Bedlington terriers was 1st reported in 1975 and the entire Dutch population was examined from 1976 until the present for presence of the disease. To examine the effect on the prevalence of the disease of excluding affected dogs from breeding we have compared 2 time cohorts, the 1st consisting of dogs born from January 1, 1976, to January 1, 1986 (n = 155), and the 2nd of dogs born from January 1, 1990, to January 1, 1997 (n = 195). The diagnosis was made in the 1st cohort by evaluating liver biopsies, and in the 2nd cohort with a DNA marker. The population was also resolved into clusters of related dogs to analyze the familial distribution of the disease in the population and to search for ancient founders of the disease among the ancestors of sick dogs. Forty-six percent of dogs examined between 1976 and 1986 had copper toxicosis. Eleven percent of dogs examined in the 2nd cohort had evidence of disease. This reduction was achieved while maintaining the already limited genetic heterogeneity of the population: the number of clusters and the mean relatedness between the clusters were similar in both time cohorts. The disease was evenly distributed over the clusters of related dogs in both cohorts. All ancestors had contributed to the distribution of copper toxicosis and no specific founders could be identified. This indicates that when the breed was established in The Netherlands, the disease was already highly prevalent in the founding dogs. 相似文献