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【目的】研究解析东亚地区柳杉属树种的遗传变异格局与种群分化,模拟其种群历史动态,为东亚植物区系演化研究和柳杉遗传资源保护提供科学依据。【方法】基于14个核基因组微卫星标记(nSSR),检测来自中国和日本共18个天然(或古树)种群的遗传变异,分析其遗传分化水平和模式,利用DIY ABC模拟其种群进化历史。【结果】柳杉属表现中等程度的遗传多样性(Ho=0.472,He=0.488),种群间具有较高的遗传分化(FST =0.136)。分子方差分析(AMOVA)结果显示,遗传变异主要来自种群内的个体间,种群内遗传变异占总变异的86.37%(P<0.001)。与地理来源一致,STRUCTURE与DAPC分析将柳杉属树种分为柳杉和日本柳杉2个地理种群,以及中国东南部、中国庐山、日本海沿岸和太平洋沿岸4个谱系。柳杉的遗传多样性(Na =4.571,Ho =0.442)低于日本柳杉(Na =4.634,Ho =0.510),但种群间存在较高的遗... 相似文献
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本文综述了自21世纪初以来DNA标记技术在国外云杉属树种中的应用情况,涉及到的树种以挪威云杉为主,多至十几种,标记种类主要包括AFLP、RAPD、RFLP、SSR、ISSR、STS、EST、VNTR和SNPs等。另外,对几种群体遗传参数进行比较分析,表明云杉天然群体遗传变异丰富,其中利用ISSR检测到白云杉天然群体多态位点百分率可达90%,利用RAPD检测到挪威云杉群体总遗传变异高至0.941;群体间存在遗传分化,产生了适应环境的变异,除一个利用mtVNTR研究所得结果外,其他研究均表明,云杉群体间遗传分化程度并不是很高,云杉群体变异主要表现为群体内变异。同时,对DNA标记在云杉属种质资源保存及遗传改良方面的前景进行了展望。 相似文献
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《内蒙古林业科技》2017,(2)
半日花是半日花科的一种半灌木或灌木,间断分布于我国内蒙古和新疆地区,由于种群数量稀少,现已被列为国家二级保护植物,开展半日花种群遗传多样性和谱系地理结构的研究对于半日花的科学保护具有重要意义。本文基于叶绿体DNA片段trnc-ycf6序列分析和AMOVA发现,半日花种群的遗传变异主要存在于居群间(93%),且居群间遗传分化很高(Gst=0.71,Fst=0.93,Nst=0.92);9个单倍型中4种为内蒙古特有,5种单倍型为新疆特有,有着显著的谱系地理学结构(NstGst)且居群间基因流较低(Nm=0.1),表明半日花种群存在地理隔离,这也是该物种现有单倍型分布格局形成的原因。单倍型最大简约树和网络状树分析,西鄂尔多斯高原可能是半日花冰期"避难所"。 相似文献
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在大、小兴安岭地区12个红皮云杉种源分布区内,分别选取调查样方,进行红皮云杉种群更新研究,同时以12个种源的144个样本为材料,采用RAPD分子标记技术进行遗传多样性研究,在种群更新研究结果的基础上分析其遗传多样性,最终为谷地红皮云杉衰退机制研究提供种群水平及分子水平的相关证据。结果表明:红皮云杉在DNA水平上具有较高的遗传变异,多态位点百分率达到98.81%;红皮云杉种源总的Nei遗传多样性指数(H)为0.363 2,Shannon指数(I)为0.540 5;种源间和种源内遗传分化分别为27.72%和72.28%,12个红皮云杉种源间的基因分化指数Gst=0.277 2,基因流系数Nm为1.304 0;各种源间具有较高水平的遗传一致度,变化范围为0.751 10.948 1。遗传距离聚类分析表明,12个种源可聚为3大类:新青、乌伊岭、红星种源为第1类;五营、友好、美溪、乌马河、带岭、南岔、双丰种源为第2类;蒙克山、塔林为第3类。种群更新数据表明:大兴安岭和小兴安岭新青、乌伊岭、红星种源为进展种群,小兴安岭五营、友好、美溪、乌马河、带岭、南岔、双丰种源为衰退种群,与遗传距离聚类分析结果一致。这一研究结果可为进一步寻找谷地云冷杉林衰退机制提供一定的数据基础,也可为红皮云杉种群遗传多样性的保护以及种群生态恢复提供科学依据。 相似文献
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《福建林业科技》2015,(3):24-28
应用ISSR分子标记技术,对沙地云杉与近缘种的种间遗传多样性进行研究,进而分析种间的亲缘关系。试验筛选出18个引物对红皮云杉、嫩江云杉、长叶云杉、粗枝云杉、白杄云杉和沙地云杉6个种进行扩增,获得171条清晰谱带,其中多态性谱带131条,多态位点百分率(PPB)为77.78%。通过POPGENE32分析表明:观察等位基因数(Na)为1.7778、有效等位基因数(Ne)为1.4803、Nei's基因多样度(He)为0.2853、Shannon多态性信息指数(I)为0.4269。采用UPGAM法聚类分析表明,6种云杉中,沙地云杉与白杄云杉亲缘关系最近,红皮云杉与嫩江云杉亲缘关系相对较近。研究结果可为云杉属的遗传评价、系统进化、物种鉴定和种间杂交育种提供参考。 相似文献
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【目的】分析长柄双花木种群遗传多样性和遗传结构,探讨其种群演化历史,加深对该物种进化过程的理解,为其遗传资源保护、开发利用提供理论基础。【方法】利用15对能获得高多态性扩增产物的SSR引物,采用TP-M13-SSR技术检测长柄双花木全分布区12个自然种群261株个体的遗传多态性,应用Gene Marker软件进行基因分型,FSTAT估算遗传参数,ARLEQUIN进行分子方差分析,STRUCTURE对所有个体进行Bayesian聚类分析,Bottleneck检测种群遗传瓶颈效应。【结果】15个SSR位点共检测到129个等位基因,平均每个位点上的等位基因数和有效等位基因数分别为8.6和3.5,观测杂合度和期望杂合度分别为0.37和0.67;种群水平上,平均每个位点上的等位基因数和有效等位基因数分别为3.4和2.1,观测杂合度和期望杂合度分别为0.35和0.43;私有基因丰富度和种群内近交系数分别为0.15和0.19。除道县种群外,其他种群极显著偏离Hardy-Weinberg平衡,表现出杂合子缺失。种群间遗传差异极显著(P0.001)。12个种群可归类为2个类群,大多数个体谱系清晰。在近期的进化过程中,种群遗传结构稳定,未经历遗传瓶颈事件。【结论】长柄双花木在物种和种群水平上,维持较丰富的遗传变异,具有较高的进化潜力。近期生境碎片化和遗传漂移对长柄双花木种群遗传多样性影响较小。种群间的自然屏障、气候变迁和人类干扰导致的种群生境碎片化,是其现代地理分布格局和种群遗传结构的主要成因,这可为该物种遗传资源保护策略的制定提供科学依据。 相似文献
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指出了生物地理学是对地球表面物种分布寻求解释的科学,其研究领域涉及生物学和地理学两个方面。在长期的自然进化历史中,动植物在地球表面的分布形成了一定的格局,这种格局尽管随着时期的变化而发生着变化,但是在特定的历史时期是相对稳定的。在今天就能看到每个树种有着其一定的自然分布区。中国幅员辽阔,具备多种气候带和气候类型,立地备件复杂多样,形成多种多样的生态气候区,为许多引种树种的生长提供了优越条件和场所。近几十年来,中国林木引种取得巨大成就。外采树种越来越成为城市绿化的重要组成部分。总结了外来树种的特点和弊端,提出了对加强外来树种应用的几点对策。 相似文献
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兴安落叶松等位酶水平的遗传多样性 总被引：1，自引：0，他引：1
兴安落叶松(Larix gmelinii)是我国高寒地区主要造林和用材树种,其群体内的遗传多样性可以反映种群进化的潜力,对基因资源保护、育种战略的制定有重要的参考价值.裸子植物遗传多样性研究可采用DNA分子标记(Kozyrenko et al.,2004;李因刚等,2008;Xu et al.,2008;张蕊等,2009),也可以采用等位酶分析技术,后者已成功地应用到松属(Pinus)(葛颂等,1988;祖元刚等,1999;虞泓等,1999)、落叶松属(Larix)(杨传平,1997;张学科等,2002)、云杉属(Picea)(张含国等,2002;罗建勋等,2006)等种群遗传多样性的研究中. 相似文献
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The evergreen Quercus alnifolia and Q. coccifera form the only interfertile pair of oak species growing in Cyprus. Hybridization between the two species has already been
observed and studied morphologically. However, little evidence exists about the extent of genetic introgression. In the present
study, we aimed to study the effects of introgressive hybridization mutually on both chloroplast and nuclear genomes. We sampled
both pure and mixed populations of Q. alnifolia and Q. coccifera from several locations across their distribution area in Cyprus. We analyzed the genetic variation within and between species
by conducting analysis of molecular variance (AMOVA) based on nuclear microsatellites. Population genetic structure and levels
of admixture were studied by means of a Bayesian analysis (STRUCTURE simulation analysis). Chloroplast DNA microsatellites
were used for a spatial analysis of genetic barriers. The main part of the nuclear genetic variation was explained by partition
into species groups. High interspecific differentiation and low admixture of nuclear genomes, both in pure and mixed populations,
support limited genetic introgression between Q. alnifolia and Q. coccifera in Cyprus. On the contrary, chloroplast DNA haplotypes were shared between the species and were locally structured suggesting
cytoplasmic introgression. Occasional hybridization events followed by backcrossings with both parental species might lead
to this pattern of genetic differentiation. 相似文献
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Charalambos Neophytou Filippos A. Aravanopoulos Siegfried Fink Aikaterini Dounavi 《European Journal of Forest Research》2011,130(4):623-635
Hybridization and introgression between Quercus alnifolia Poech and Q. coccifera L. is studied by analyzing morphological traits, nuclear and chloroplast DNA markers. The study site is a mixed stand on
Troodos Mountains (Cyprus), and the analyzed material includes both adult trees and progenies of specific mother trees. Multivariate
analysis of morphological traits shows that the two species can be well distinguished using simple leaf morphometric parameters.
A lower genetic diversity in Q. alnifolia than in Q. coccifera and a high interspecific differentiation between the two species are supported by an analysis of nuclear and chloroplast
microsatellites. The intermediacy of the four designated hybrids is verified by both leaf morphometric and genetic data. Analysis
of progeny arrays provides evidence that interspecific crossings are rare. This finding is further supported by limited introgression
of chloroplast genomes. Reproductive barriers (e.g. asynchronous phenology, postzygotic incompatibilities) might account for
this result. A directionality of interspecific gene flow is indicated by a genetic assignment analysis of effective pollen
clouds with Q. alnifolia acting as pollen donor. Differences in flowering phenology and species distribution in the stand may have influenced the
direction of gene flow and the genetic differentiation among effective pollen clouds of different mother trees within species. 相似文献
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Cyclobalanopsis glauca is a dominant species of evergreen broad-leaved forests in mainland China. This study compares the genetic variation of an artificially regenerated population with its donor population and two other wild populations, by using RAPD markers. A total of 74 clear, reproducible bands were scored for 12 RAPD primers; 72 were polymorphic (P = 97.3%). AMOVA revealed that most genetic variation was within populations and only 10.35% was among populations. Various measures indicated that there is no difference in genetic diversity between the planted and the original populations. ΦST between the planted offspring population and the donor population was larger than those between the planted and other two natural populations, indicating that artificial regeneration might lead to biased genetic composition, given that temporal differentiation is usually lower than spatial differentiation. This divergence may be due to unequal seed production among the maternal individuals and viability differences among seeds. 相似文献
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Alnus trabeculosa Hand.-Mazz. is classed as “near threatened,” and efforts should be made to conserve the species, but effective action would
require understanding of its genetic variation and structure. Therefore, the genetic variation at 12 isozyme loci was examined
in seven populations of the species in Japan. The expected heterozygosity within species (H
es=0.222) and the expected heterozygosity within populations (H
ep=0.199) were found to be slightly higher than in most other woody species. The coefficient of genetic differentiation (G
ST=0.146) was also high. The northernmost population had the lowest values for almost all measures of genetic variation, and
populations in southern Japan tended to show greater within-population variation than those in northern Japan. The level and
distribution of genetic variation in this species might be related to its life history and ecological traits, and distribution
history. 相似文献
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[目的]通过我国无患子主要分布区的居群样本,研究无患子天然居群的遗传多样性和遗传结构.[方法]采用ISSR分子标记技术,利用12条ISSR引物分析18个天然居群的265株个体样本.[结果]表明无患子遗传多样性水平较高,物种和居群水平上的多态位点百分率 (PPB)分别为95.37%和57.82%,Shannon's信息指数(I)分别为0.256 9和0.199 8,Nei's遗传多样性指数(H)分别为0.390 9和0.298 0.AMOVA分析表明,18个居群间出现一定程度的遗传分化,且遗传变异主要发生在居群内.UPGMA聚类和Mantel检验结果表明,18个天然居群可分为2大组群,且居群间的地理距离与遗传距离之间不存在显著相关性(r=0.066 7,P=0.541 7>0.05).[结论]无患子以自交为主,其天然居群遗传多样性丰富,居群内的遗传多样性高于居群间.研究结果可为无患子育种策略的科学制定和种质资源的有效保护及利用提供理论依据. 相似文献
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Dhiraj Naik Durgeshwer Singh Varsha Vartak Sharayu Paranjpe Sujata Bhargava 《New Forests》2009,38(1):99-115
Gmelina arborea is an important timber-yielding tree that grows naturally in the tropical and subtropical regions of Southeast Asia and has
also been introduced as a plantation species outside these regions. Genetic diversity in this tree species was observed in
stone/seed-related traits and in vitro responses of cultured nodal segments from plants of eight different populations representing
natural forests, fragmented forests and plantations. Variance analysis showed significant differences between populations
for these traits. However, it was not possible to separate the different populations using these traits by multivariate analysis,
even after environmental variation was reduced over six subcultures. Genetic diversity was therefore analysed using molecular
markers. Inter-simple sequence repeat (ISSR) primers yielded 95% polymorphic loci among the eight populations and UPGMA analysis
enabled separation of these populations on the basis of their genetic distances. Diversity was also analyzed using population
genetics parameters like Nei’s genetic diversity and gene differentiation. Nei’s genetic diversity was 0.29 between populations
and 0.11 within populations. AMOVA analysis indicated 41 and 59% within- and between-population genetic diversity, respectively.
Mantel test suggested that genetic differentiation between six Indian populations was positively correlated to geographic
distance (r = 0.626, P = 0.029). Assessment of the genetic variation in G. arborea populations is an important step in selection of conservation strategies for this species since diversity forms the basis
for species adaptation. 相似文献
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Taxus wallichiana is one of the most important medicinal tree species of the Himalayan region. Leaf and bark of the species yield an important
drug called taxol, which is used for treatment of many types of cancer. There is a serious threat to the existence of the
species due to over exploitation in its native habitat. Adequate information on the nature and the extent of genetic diversity
in this important species is required for developing suitable strategy for its conservation. Random amplified polymorphic
DNA (RAPD) and amplified fragment length polymorphism (AFLP) were used to assess genetic variation in nine natural populations
of T. wallichiana from western part of the Himalayan ranges. Both the markers revealed low genetic diversity in these populations. Average
heterozygosity for AFLP and RAPD were 0.3715 and 0.3072, respectively. ΦST values derived from molecular variance were 0.0855 and 0.1005 for AFLP and RAPD, respectively, whereas the corresponding
GST values were 0.1796 and 0.2140. Most part of the genetic variation was present within the populations. However, between population
variation was low but statistically significant, which suggested that the sampled populations might not constitute a single
panmictic population. Cluster analysis and Mantel’s correlation revealed that genetic differentiation broadly followed geographic
distribution of the populations. T. wallichiana thus urgently needs to be conserved using both in situ and ex situ conservation approaches. 相似文献
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[目的]研究毛红椿天然群体遗传多样性取样策略,为其种质资源收集、保存和遗传多样性保护等提供参考依据。[方法]利用8对微卫星分子标记进行毛红椿天然群体遗传多样性和空间自相关分析,综合制定其天然群体合理取样策略。[结果]毛红椿天然群体等位基因数平均为7.5个,期望杂合度(H_e)和多态性信息指数(PIC)均值分别为0.643 7和0.636 0,基因分化系数(G_(ST))均值为0.290 7。在遗传多样性取样策略方面,提出了根据毛红椿群体基因分化系数来确定取样群体遗传变异所占总变异比例的运算公式为1-(G_(ST))~(n-1),其中,n为取样群体的数量。当取样群体达到4个时,基本上能包括该树种97.5%的遗传变异;同时确定了目标群体的选择方法,应选择与其它群体间基因分化系数均值较大的4个群体,即贵州册亨(CH)、浙江遂昌(SC)、浙江仙居(XJ)和云南师宗(SZ)。通过构建云南宾川(BC)、云南师宗(SZ)和江西宜丰(YF)群体内取样单株数量与基因多样性和等位基因之间的捕获曲线,确定了群体内取样单株数量应达到15个以上;毛红椿天然群体内300～520 m范围内的单株间存在相似关系,超出此范围个体间差别较大,说明在进行群体内单株取样时,单株间距应大于520 m。[结论]取样群体数量、群体间遗传分化系数、群体内单株数量以及单株间距离等影响了毛红椿取样群体的遗传多样性。毛红椿天然群体遗传多样性取样策略为取样群体4个、每个群体最少取样15个单株,单株间距大于520 m。 相似文献
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The genetic diversity and genetic variation within and among populations of five natural Davidia involucrata populations were studied from 13 primers based on random amplified polymorphic DNA (RAPD) analysis. The results show that
natural D. involucrata population has a rich genetic diversity, and the differences among populations are significant. Twenty-six percent of genetic
variation exists among D. involucrata populations, which is similar to that of the endangered tree species Liriodendron chinense and Cathaya argyrophylla in China, but different from more widely distributed tree species. The analysis of the impacts of sampling method on genetic
diversity parameters shows that the number of sampled individuals has little effect on the effective number of alleles and
genetic diversity, but has a marked effect on the genetic differentiation among populations and gene flows. This study divides
the provenances of D. involucrata into two parts, namely, a southeast and a northwest provenance.
Translated from Scientia Silvae Sinicae, 2004, 40(4) (in Chinese) 相似文献