鄱阳湖具刚毛荸荠居群遗传多样性和克隆结构的初步研究

采用ISSR标记对鄱阳湖的2个具刚毛荸荠(Heleocharis valleculosa f.setosa)居群共120个个体的遗传多样性和克隆结构进行了研究.5条ISSR引物共检测到85个位点,其中49个为多态位点,占57.65%.具刚毛荸荠具有较高的遗传多样性(在物种水平上,Nei's基因多样性指数H=0.1545,Shannon信息指数I=0.2400),两居群间遗传分化很小.具刚毛荸荠的克隆多样性很高(D=0.9975),两居群不具有共同的基因型.空间自相关分析表明,具刚毛荸荠居群内遗传变异为随机分布格局.     

黄花杓兰云南中甸居群遗传结构及克隆多样性的分析

采用AFLP分子标记方法对云南中甸的6个黄花杓兰( Cypripedium flavum )居群进行了遗传多样性水平、遗传结构及克隆多样性研究,其中两个居群用样方取样法分析其克隆空间结构.POPGENE软件分析结果表明:两组引物共产生104个位点,其中86个为多态位点,多态位点百分率为82.69%.黄花杓兰具有丰富的遗传变异(物种水平上, He=0.2884, Ho=0.4312;居群水平上,P=64.59%, He=0.2449, Ho=0.3606),黄花杓兰居群的遗传分化不大( Gst=0.154),居群间基因交流较为频繁( Nm=2.7460).居群的克隆多样性水平高( D=0.9638-0.9960,G/N=0.83-0.96),同一克隆的分株相邻,克隆生长延伸范围狭窄.黄花杓兰居群之所以保持较高水平的遗传多样性,可能与其既能通过实生幼苗增加基因的杂合度,又能通过无性分株把杂合体固定下来有关.     

侯晨曦：附表1-附表2

本研究基于7个叶绿体DNA片段（cpDNA）和2个核DNA片段（ITS和PZ8）的测序数据,对龙血树柴胡（Bupleurum dracaenoides Huan C.Wang,Z.R.He&H.Sun）8个居群的153个样本进行了遗传多样性和分布式样研究。cpDNA片段分析结果显示：龙血树柴胡在物种水平具有较高的遗传多样性（H_d=0.862;P_i=0.00567）,但居群内遗传多样性低,遗传变异主要存在于居群间,遗传分化显著（F_st=0.959）;而核DNA片段ITS和PZ8的数据分析结果显示,其遗传多样性较低（H_d=0.532,P_i =0.00121和H_d=0.349,P_i=0.00060）,遗传变异主要存在于居群内,居群间仅存在一定程度的遗传分化。中性检验和失配分布分析结果发现龙血树柴胡没有经历过近期种群扩张事件,8个居群的153个样本从遗传成份上可被分为两组。研究结果将为龙血树柴胡的资源保护和发掘提供参考。     

珍稀濒危植物太行菊遗传多样性的ISSR分析

利用ISSR分子标记技术对太行山特有濒危物种太行菊11个自然居群的遗传多样性进行研究。用10个引物对11个居群的122个样品进行扩增,共得到150个扩增位点,其中多态性位点149个,多态位点百分率(PPL)为99.33%。POPGENE分析显示,太行菊具有较高的遗传多样性(H=0.2149,I=0.3455)。沁阳市大西天居群的遗传多样性水平最高(H=0.1910,I=0.2969),山西陵川县大双村居群的遗传多样性水平最低(H=0.1356,I=0.2155)。Nei’s遗传多样性分析表明,11个自然居群间出现了较高的遗传分化(基因分化系数Gst=0.2566,基因流Nm=1.4488)。生境的的片段化和基因流障碍可能是导致太行菊居群间遗传分化显著的主要原因。通过对太行菊居群遗传多样性和遗传结构的分析,该文提出了一些保护策略。     

异叶泽兰的遗传多样性和居群历史动态研究

异叶泽兰属于菊科泽兰属,是该属分布海拔相对较高的植物,分布在青藏高原东部和横断山海拔1700~3000 m的地区。该文利用ycf6-psbM和rpl32-trnL两个叶绿体DNA(cpDNA)片段以及核DNA片段ITS(nITS)作为分子标记,研究了异叶泽兰的遗传多样性及其分布特征,探讨了其居群历史动态。结果表明:(1)叶绿体片段联合分析结果显示,异叶泽兰在物种水平遗传多样性水平不高,单倍型多态性指数(H_d)为0.656,核苷酸多态性(π)为0.00161;而ITS的基因型多态性指数(H d)为0.687,核苷酸多态性(π)为0.00235。(2)cpDNA和nITS分析结果均显示,异叶泽兰居群水平总的遗传多样性大于居群内平均遗传多样性,遗传变异主要发生在居群间,居群间存在明显的遗传分化(cpDNA:G_st=0.679,N_st=0.655,F st=0.655;nITS:G_st=0.543,N_st=0.370,F_st=0.584),但是由于N_st值小于G_st值,因此异叶泽兰的分布不具有明显的谱系地理结构。(3)基于单倍型地理分布以及Network分析推测,横断山区南部(川西南-滇西北)和云南中部可能是异叶泽兰在第四纪冰期时的两个避难所,中性检验和失配分析的结果支持异叶泽兰在冰期后未发生过居群扩张。     

白木香遗传多样性研究

用ISSR分子标记技术对白木香(Aquilaria sinensis(Lour.)Gilg)的遗传多样性进行分析.结果表明,白木香物种水平的遗传多样性较高,而居群水平的遗传多样性相对较低,其中广东茂名居群的遗传多样性最高.白木香居群间存在较大的遗传分化,遗传分化系数G_(ST)=0.4425,表明居群内遗传分化大于居群间的分化.UPGMA聚类分析表明白木香分化为两个谱系,其中谱系Ⅰ由广东、福建、海南的5居群组成,谱系Ⅱ由广西、云南的3个居群组成.居群间的基因交流受到阻碍(Nm=0.6633<1),阻碍主要产生于两个谱系间,而谱系内部的居群间在较近的历史时期基因交流频繁(Nm分别为1.4382和1.2333),谱系分化的原因主要是地理因素,两谱系交界处有云开山脉等形成的天然屏障,阻碍物种的扩展和基因交流.     

濒危植物毛瓣金花茶遗传多样性的ISSR分析

采用ISSR分子标记对毛瓣金花茶6个自然居群的遗传多样性进行了分析。利用11个引物对150个个体进行了扩增,共扩增出92条条带,其中多态性条带74条。毛瓣金花茶在物种水平和居群水平都表现出相对较高的遗传多样性,在物种水平上,多态位点百分率(PPB)为80.43%,Nei’s基因多样性指数(h)为0.245 1,Shannon多样性指数(I)为0.377 6;在居群水平上,PPB为58.70%~66.30%,h为0.199 7~0.229 3,I为0.300 9~0.343 8。Nei’s遗传多样性分析和AMOVA分析表明,毛瓣金花茶的遗传变异主要存在于居群内,居群间的遗传分化程度较低(Gst=0.126 6,Φst=11.37%),基因流(Nm)为3.448 0。Mantel检测表明,居群间的遗传距离和地理距离之间存在显著的相关关系(r=0.755 1,P0.05)。研究认为,毛瓣金花茶较高的遗传多样性和较低的遗传分化可能与其异交型繁育系统和鸟类传粉有关。     

同域分布垂穗披碱草和达乌力披碱草遗传多样性和遗传结构分析

披碱草属(Elymus L.)是禾本科(Poaceae)小麦族(Triticeae)中的一个多年生属,该属在青藏高原地区有广泛分布,多数物种是草原和草甸的组成成分,许多种类为品质优良的牧草。垂穗披碱草(E.nutans)和达乌力披碱草(E.dahuricus)同为禾本科小麦族披碱草属异源六倍体物种,染色体组组成皆为StYH。为探究垂穗披碱草遗传多样性形成的内在机制,该研究利用微卫星(SSR)分子标记,对采自青藏高原地区同域分布的垂穗披碱草和达乌力披碱草两个居群共58个个体进行遗传多样性和遗传结构分析。结果表明:8对引物在垂穗披碱草和达乌力披碱草扩增条带分别为163条和124条,多态性位点百分率(PPB)分别为89.71%和76.07%,多态性信息含量(PIC)分别介于0.583~0.929和0.524~0.830之间。垂穗披碱草遗传多样性(H_e=0.69,I=1.34,P_p=100%)高于达乌力披碱草(H_e=0.53,I=0.80,P_p=93.75%);同域分布的垂穗披碱草和达乌力披碱草居群,垂穗披碱草呈现出更高的遗传多样性。AMOVA分子变异显示,两个物种居群内遗传变异分别80.92%和63.62%,但居群间遗传分化水平较低。遗传结构分析揭示两个物种间有基因流存在。综合分析结果认为,该地区种间杂交基因渗透引起的种内遗传分化,在这两个物种多样性形成中可能起着重要作用。     

武陵山区蛇足石杉遗传多样性的AFLP分析

采用AFLP分子标记对武陵山区蛇足石杉(Huperzia serrata)4个居群进行遗传多样性的研究,结果表明:(1)7对引物组合共扩增出条带615条,其中549条为多态性条带;在物种水平上,多态性条带百分率PPB=89.27%,有效等位基因数Ne=1.257,Nei’s基因多样度指数H=0.178,Shannon多样性信息指数Isp=0.298;在居群水平上,PPB=71.42%,Ne=1.235,H=0.154,Shannon多样性信息指数Ipop=0.251;遗传多样性在居群间有明显的差别,其中坪坝营(PBY)居群最高(PPB=81.95%),而铁峰山(TFS)居群最低(PPB=64.55%)。(2)居群间的遗传分化较低,基于Nei’s基因多样性分析结果显示,居群间遗传分化系数GST=0.159;Shannon’s居群分化系数[(Isp-Ipop)/Isp]为0.16;WINAMOVA分析显示,武陵山区蛇足石杉的遗传变异主要存在于居群内,居群内的遗传变异分量为65.057,占总变异的75.77%,而居群间的遗传变异分量为20.804,占总变异的24.23%;居群内存在极显著的遗传分化(ΦST=0.242,P0.001)。(3)由遗传分化系数(GST)估计,武陵山区蛇足石杉居群间的基因流Nm=2.647,表明蛇足石杉属于异交种。(4)两两居群间的Nei’s遗传一致度(IN)范围为0.031 0~0.969 4;Mantel检测结果显示,居群间的遗传距离与地理距离之间不存在显著的正相关关系(r=0.269,P=0.887)。研究认为,遗传多样性与遗传结构主要决定于居群历史,较少干扰而稳定的居群偏向克隆生殖,遗传多样性较低,而新建居群的遗传多样性则较高;克隆生长、生态位选择、异交,以及有效的孢子风媒传播等可能是其维持较高遗传多样性水平的因素,而过度采挖等人类活动和生境片断化是导致蛇足石杉濒危的主要因素。     

准噶尔无叶豆片断化居群的遗传变异及克隆多样性

准噶尔无叶豆(Eremosparton songoricum)是豆科无叶豆属小半灌木, 既能开花结实进行有性繁殖, 又可以靠根茎进行无性克隆繁殖, 为国家三级保护植物, 在中国仅片断化分布于新疆古尔班通古特沙漠局部区域。本文采用ISSR分子标记对采自古尔班通古特沙漠腹地及边缘的7个准噶尔无叶豆自然居群共148个个体进行了遗传变异和克隆多样性分析。8个引物共扩增出84个位点, 其中77个为多态性位点, 物种水平上的多态位点百分比PPB为91.67％, Nei's基因多样性指数I为0.3192, Shannon信息指数H为0.3540; 居群水平上的多态位点百分比PPB为58.45％, Nei's基因多样性指数I为0.2248, Shannon信息指数H为0.3270。居群间的遗传分化系数G_ST为0.2978。AMOVA分析表明, 有31.88%的遗传变异存在于居群间, 表明居群间存在显著的遗传分化。克隆多样性分析表明, 居群水平上, 居群G的Simpson多样性指数和均匀度指数最高, 分别为0.9400和0.9885; 居群E最低, 分别为0.8457和0.9021。物种水平上, Simpson多样性指数为0.9858, 均匀度指数为0.9673。本研究结果表明, 和其他荒漠植物相比, 准噶尔无叶豆表现出较高的遗传变异水平和克隆多样性, 这主要与该物种兼性生殖的繁育方式及多克隆起源有关; 而居群间产生了显著的遗传分化则主要由于人为干扰引起的生境片断化和居群减小而导致的基因交流障碍所致。遗传变异水平和遗传结构的研究将为分析准噶尔无叶豆致濒原因及进化潜力提供重要资料, 对该物种保护具有指导意义。     

Clonal diversity of Clintonia udensis Trautv. et Mey. populations and its correlation with ecological factors

The clonal diversity of Clintonia udensis Trautv.et Mey.was detected by ISSR markers among 16 populations,and its correlation with ecological factors was analyzed as well in this work.Results showed that individuals(clonal ramets)per genotype were 1.12 and 1.149 at population and species levels,respectively,and that the 16 populations were all multiclonal.The detected genotypes were localized,without exception,within populations but demonstrated relatively high clonal differentiation among populations.The clonal diversity of the studied populations was high,with the average Simpson's index of 0.975,while the genets showed a clonal architecture of"guerilla".The population genetic diversities revealed by genet were consistent with those by ramet,further confirming their genetic differentiation among populations.And its genotype diversity within populations probably resulted largely from the frequent seedling regeneration and self-compatibility.In addition,the correlation analysis further revealed that,among the ecological factors,Simpson's index of C.udensis had a significant positive correlation(P<0.05)with pH values in the soil but not others.     

Clonal diversity of <Emphasis Type="Italic">Clintonia udensis</Emphasis> Trautv. <Emphasis Type="Italic">et</Emphasis> Mey. populations and its correlation with ecological factors

The clonal diversity of Clintonia udensis Trautv. et Mey. was detected by ISSR markers among 16 populations, and its correlation with ecological factors was analyzed as well in this work. Results showed that individuals (clonal ramets) per genotype were 1.12 and 1.149 at population and species levels, respectively, and that the 16 populations were all multiclonal. The detected genotypes were localized, without exception, within populations but demonstrated relatively high clonal differentiation among populations. The clonal diversity of the studied populations was high, with the average Simpson’s index of 0.975, while the genets showed a clonal architecture of “guerilla”. The population genetic diversities revealed by genet were consistent with those by ramet, further confirming their genetic differentiation among populations. And its genotype diversity within populations probably resulted largely from the frequent seedling regeneration and self-compatibility. In addition, the correlation analysis further revealed that, among the ecological factors, Simpson’s index of C. udensis had a significant positive correlation (P<0.05) with pH values in the soil but not others.     

Clonal and spatial genetic structure in natural populations of Luohanguo (Siraitia grosvenorii), an economic species endemic to South China,as revealed by RAPD markers

Clonal growth is generally expected to have significant effects on the spatial genetic structure within populations. In this study, random amplified polymorphic DNA (RAPD) markers were used to reveal clonal and spatial genetic structure of four natural populations of Luohanguo (Siraitia grosvenorii), an economic vine species endemic to South China. A total of 351 ramets were assigned to 76 distinct multi-locus genotypes (i.e. genets), with the G/N varying from 0.121 to 0.350. No widespread genet was found across different populations. The clonal diversity (D) and evenness (E) ranged from 0.333 to 0.828 and from 0 to 0.741, respectively. While most genets consisted of fewer than five ramets, we observed some dominant genets that had much more (up to 69) ramets and spread over large areas. Spatial autocorrelation analyses revealed a spatial genetic structure (i.e. significant positive autocorrelation within 20 m and negative autocorrelation beyond 40 m) in one population, but not in other three populations with smaller population size. This study highlights the importance of clonal growth in shaping the spatial genetic structure in Luohanguo, which may have complex effects on the dynamics and evolution of its declining populations.     

Clonal diversity and structure within a population of the pondweed Potamogeton pectinatus foraged by Bewick's swans

Clonal diversity within plant populations is affected by factors that influence genet (clone) survival and seed recruitment, such as resource availability, disturbance, seed dispersal mechanism, propagule predation and the age of the population. Here we studied a population of Potamogeton pectinatus, a pseudo-annual aquatic macrophyte. Within populations reproduction appears to be mainly asexually through subterranean propagules (tubers), while recruitment via seeds is believed to be relatively unimportant. RAPD markers were used to analyse clonal diversity and genetic variation within the population. Ninety-seven genets were identified among 128 samples taken from eight plots. The proportion of distinguishable genets (0.76) and Simpson's diversity index (0.99) exhibited high levels of clonal diversity compared to other clonal plants. According to an analysis of molecular variance (amova) most genetic variation occurred between individuals within plots (93-97%) rather than between plots (8-3%). These results imply that sexual reproduction plays an unexpectedly important role within the population. Nevertheless, autocorrelation statistics revealed a spatial genetic structure resulting from clonal growth. In contrast to genetic variation, clonal diversity was affected by several ecological factors. Water depth and silt content had direct negative effects on clonal diversity. Tuber predation by Bewick's swans had an unexpected indirect negative effect on clonal diversity through reducing the tuber-bank biomass in spring, which on its turn was positively correlated to clonal diversity. The disturbance by swans, therefore, did not enhance seed recruitment and thus clonal diversity; on the contrary, heavily foraged areas are probably more prone to stochastic loss of genets leading to reduced clonal diversity.     

特有珍稀濒危植物景东报春遗传多样性的ISSR分析

景东报春(Primula interjacens Chen)是一分布在中国云南中南部的稀有的、分布区狭窄的特有种.该种含2个变种:原变种景东报春(P.interjacens Chen var.interjacens),现存一个居群;和光叶景东报春(P.interjacens Chen var.epilosa C.M.Hu),有2个居群.本文用ISSR分子标记对景东报春现存的3个居群进行了遗传多样性分析.和我们最初的预计相反,尽管居群小、分布区狭窄,景东报春的遗传多样性却很高(在居群水平的多态位点率P=59.75%,基因多样性HE=0.236 8,Hpop=0.345 9;在种的水平的多态位点率P=75.47%,遗传多样性HT=0.320 5,总的遗传多样性Hsp=0.4618).推测异型花和杂交可能是维持高的遗传多样性的原因.Nei的遗传多样性水平(26.13%)和Shannon多样性指数(25.09%)显示居群间存在中度分化.尽管景东报春原变种和变种在形态上有区别,但用非加权配对算数平均法(UPGMA)聚类分析的结果表明,两者并没有明显的遗传分化,可处理为一个单一的分类单元.基于观察到的居群遗传信息,建议采取就地保护和迁地保护的保护措施.     

CONTRIBUTIONS OF SEXUAL AND ASEXUAL REPRODUCTION TO POPULATION STRUCTURE IN THE CLONAL SOFT CORAL,ALCYONIUM RUDYI

Numerous studies of population structure in sessile clonal marine invertebrates have demonstrated low genotypic diversity and nonequilibrium genotype frequencies within local populations that are monopolized by relatively few, highly replicated genets. All of the species studied to date produce planktonic sexual propagules capable of dispersing long distances; despite local genotypic disequilibria, populations are often panmictic over large geographic areas. The population structure paradigm these species represent may not be typical of the majority of clonal invertebrate groups, however, which are believed to produce highly philopatric sexual propagules. I used allozyme variation to examine the population structure of the temperate soft coral, Alcyonium rudyi, a typical clonal species whose sexually produced larvae and asexually produced ramets both have very low dispersal capabilities. Like other clonal plants and invertebrates, the local population dynamics of A. rudyi are dominated by asexual reproduction, and recruitment of new sexually produced genets occurs infrequently. As expected from its philopatric larval stage, estimates of genetic differentiation among populations of A. rudyi were highly significant at all spatial scales examined (mean θ = 0.300 among 20 populations spanning a 1100-km range), suggesting that genetic exchange seldom occurs among populations separated by as little as a few hundred meters. Mapping of multilocus allozyme genotypes within a dense aggregation of A. rudyi ramets confirmed that dispersal of asexual propagules is also very limited: members of the same genet usually remain within < 50 cm of one another on the same rock surface. Unlike most previously studied clonal invertebrates, populations of A. rudyi do not appear to be dominated by a few widespread genets: estimates of genotypic diversity (G_o) within 20 geographically distinct populations did not differ from expectations for outcrossing, sexual populations. Despite theoretical suggestions that philopatric dispersal combined with typically small effective population sizes should promote inbreeding in clonal species, inbreeding does not appear to contribute significantly to the population structure of A. rudyi. Genet genotype frequencies conformed to Hardy-Weinberg expectations in all populations, and inbreeding coefficients (f) were close to zero. In general, the population structure of A. rudyi did not differ significantly from that observed among outcrossing sexual species with philopatric larval dispersal. Age estimates suggest, however, that genets of A. rudyi live for many decades. Genet longevity may promote high genotypic diversity within A. rudyi populations and may be the most important evolutionary consequence of clonal reproduction in this species and the many others that share its dispersal characteristics.     

Local forest environment largely affects below-ground growth, clonal diversity and fine-scale spatial genetic structure in the temperate deciduous forest herb Paris quadrifolia

Paris quadrifolia (herb Paris) is a long-lived, clonal woodland herb that shows strong differences in local population size and shoot density along an environmental gradient of soil and light conditions. This environmentally based structuring may be mediated by differences in clonal growth and seedling recruitment through sexual reproduction. To study the interrelationship between environmental conditions and spatial patterns of clonal growth, the spatial genetic structure of four P. quadrifolia populations growing in strongly contrasting sites was determined. In the first place, plant excavations were performed in order to (i) determine differences in below-ground growth of genets, (ii) investigate connectedness of ramets and (iii) determine total genet size. Although no differences in internode length were found among sites, clones in moist sites were much smaller (genets usually consisted of 1-3 interconnected shoots, most of them flowering) than genets in dry sites, which consisted of up to 15 interconnected shoots, the majority of which were vegetative. Further, amplified fragment length polymorphism (AFLP) markers were used. Clonal diversity was higher in populations located in moist and productive ash-poplar forests compared to those found in drier and less productive mixed forest sites (G/N: 0.27 and 0.14 and Simpson's D: 0.84 and 0.75, respectively). Patterns of spatial population genetic structure under dry conditions revealed several large clones dominating the entire population, whereas in moist sites many small genets were observed. Nevertheless, strong spatial genetic structure of the genet population was observed. Our results clearly demonstrate that patterns of clonal diversity and growth form of P. quadrifolia differ among environments. Limited seedling recruitment and large clone sizes due to higher connectedness of ramets explain the low clonal diversity in dry sites. In moist sites, higher levels of clonal diversity and small clone sizes indicate repeated seedling recruitment, whereas strong spatial genetic structure suggests limited seed dispersal within populations.     

羊草种群克隆多样性的初步研究

 采用水平淀粉凝胶电泳技术检测了松嫩草原上两种叶色类型(灰绿型和黄绿型)羊草(Leymus chinensis)种群的克隆多样性。羊草种群中克隆多样性较高,Simpson指数平均为0.983,97.7% 的基因型为局部分布;在克隆特性上,灰绿型和黄绿型羊草也明显不同,黄绿型种群的克隆多样性低于灰绿型。由基株数据计算的种群遗传多样性与由分株计算的结果一致,进一步确认了黄绿型和灰绿型羊草间存在着明显的遗传分化。种群中不时有实生苗补充及环境异质性引起的分化选择作用可能是维持种群内基因型多样性的重要因素。     

竹叶眼子菜居群遗传多样性和克隆结构

采用ISSR技术对长江中游南岸豹澥湖和大冶湖不同生境中的竹叶眼子菜(Potamogeton malaianus)居群的遗传多样性及克隆结构进行了研究.结果表明,在两居群的106株个体中,利用6条ISSR引物共得到40条符合3/N标准并无连锁不平衡的清晰位点,竹叶眼子菜具有较高的遗传多样性,其多态位点百分率为75.0％,Shannon多样性指数为0.3736, 两居群的遗传分化很小.竹叶眼子菜的克隆多样性很高(D=0.9917),两居群间的克隆分化很大,不具有共有的基因型.竹叶眼子菜的基株分布为游击型构型,位于湖心的大冶居群克隆距离(3.0～31.5 m)明显地大于湖岸豹澥居群(2.4～6.7 m).     

Clonal and fine-scale genetic structure in populations of a restricted Korean endemic, Hosta jonesii (Liliaceae) and the implications for conservation

BACKGROUND AND AIMS: In plant populations the magnitude of spatial genetic structure of apparent individuals (including clonal ramets) can be different from that of sexual individuals (genets). Thus, distinguishing the effects of clonal versus sexual individuals in population genetic analyses could provide important insights for evolutionary biology and conservation. To investigate the effects of clonal spread on the fine-scale spatial genetic structure within plant populations, Hosta jonesii (Liliaceae), an endemic species to Korea, was chosen as a study species. METHODS: Using allozymes as genetic markers, spatial autocorrelation analysis of ramets and of genets was conducted to quantify the spatial scale of clonal spread and genotype distribution in two populations of H. jonesii. KEY RESULTS: Join-count statistics revealed that most clones are significantly aggregated at < 3-m interplant distance. Spatial autocorrelation analysis of all individuals resulted in significantly higher Moran's I values at 0-3-m interplant distance than analyses of population samples in which clones were excluded. However, significant fine-scale genetic structure was still observed when clones were excluded. CONCLUSIONS: These results suggest that clones enhance the magnitude of spatial autocorrelation due to localized clonal spread. The significant fine-scale genetic structure detected in samples excluding clones is consistent with the biological and ecological traits exhibited by H. jonesii including bee pollination and limited seed dispersal. For conservation purposes, genetic diversity would be maximized in local populations of H. jonesii by collecting or preserving individuals that are spaced at least 5 m apart.