RSAP、SSR和SRAP分析马铃薯遗传多样性的应用比较

本研究分别利用RSAP、SSR和SRAP对15份马铃薯种质进行遗传多样性分析,比较3种分子标记的分析效力。结果表明,平均每对引物扩增出的多态性位点RSAP(5.75个)SSR(6.33个)SRAP(7.75个);RSAP+SSR+SRAP联合聚类的结果与SRAP和RSAP聚类结果基本一致,相关性分别达到极显著和显著水平,与SSR的聚类结果基本相似,呈显著相关性。在分析马铃薯遗传多样性中,SRAP标记的效果最优,SSR标记效果略优于RSAP标记。RSAP分子标记能较好地分析马铃薯的遗传多样性,而以RSAP+SSR+SRAP联合分析,则能更好地评估种质的遗传多样性和亲缘关系。     

基于SSR标记分析小豆及其近缘植物的遗传关系

本研究利用87对SSR引物分析了80份栽培小豆(Vigna angularis)、22份野生小豆(V.angularis var.nipponensis)以及10份豇豆属(共7个种)近缘植物,旨在比较豇豆属不同种的遗传多样性,并分析种间的遗传关系.结果显示87对SSR引物在112份小豆及其近缘植物资源中共检测到667个等位变异.其中有75个、71个和82个SSR位点分别在栽培小豆、野生小豆和近缘植物中表现为多态.随机抽样分析发现,平均每SSR位点检测到的等位变异数目为近缘植物>野生小豆>栽培小豆,与多态信息含量(PIC)值一致,说明近缘植物及野生小豆中蕴含着丰富的遗传变异,是栽培小豆育种的重要基因来源.聚类分析显示,栽培小豆、野生小豆和近缘植物间的遗传分化比较明显,分别聚为三大类,其中栽培小豆的遗传背景与其生态环境相对应;近缘植物又可以分为三个亚类,亚类间的遗传距离与其亲缘关系相对应.本研究结果也说明利用SSR标记辅助豇豆属的种间分类是可行的.     

七种风铃草属植物亲缘关系的ISSR分析

为了解四川风铃草属植物的资源丰富度和遗传进化情况,该研究利用ISSR分子标记,探究了四川7种风铃草属植物的亲缘关系,为风铃草属植物的分子标记辅助鉴定、资源保护、花卉品种的开发与育种提供理论基础。结果表明:40条ISSR引物中有28条引物能够扩增出清晰的条带,扩增总条带数为164,其中有98.8%的扩增条带具有多态性,供试的7种风铃草属植物遗传相似性系数在0.421～0.945之间,其中钻裂风铃草与藏滇风铃草的遗传相似度最高为0.945,说明它们之间的亲缘关系很近。此外,ISSR分子标记聚类结果表明,7种风铃草属植物可以明显聚为4大类:西南风铃草、灰毛风铃草、灰岩风铃草为一类;紫斑风铃草与流石风铃草各成一类,这两种在形态上与其它各种风铃草差异较大;最后是钻裂风铃草与藏滇风铃草为一类。     

SSR分子标记在山茶属观赏资源遗传多样性研究中的应用

采用微卫星(SSR)分子标记的方法,利用20对SSR引物对33份山茶属资源(含种和品种)的DNA样品进行了PCR扩增,从中筛选出10对扩增效果较好的SSR引物,并对33份资源进行了遗传多样性分析。结果显示:10对引物在33个植物材料中共检测出123个等位基因,每个SSR位点的等位基因数为3~22个,SSR2引物检测到的等位基因数量最多,达22个,平均每对引物含有12.3个等位基因,平均多态性信息量为0.74,变化范围为0.06~0.96。利用遗传距离矩阵按UPGMA方法进行聚类,结果表明33份植物材料可分为9个分支,很好的区分了品种间的亲缘关系,可为杂交育种的组合选择提供理论基础。不同花型的山茶属植物在10个微卫星位点上共发现42个特异等位基因,可能与不同的花型性状有关。     

丝兰属6种植物叶绿体基因组特征分析

为了理清丝兰属（Yucca）叶绿体基因组特征和序列变异情况,进行丝兰属植物叶绿体比较基因组学分析,并构建基于叶绿体基因组的系统发育树。利用高通量测序技术获得无刺龙舌兰（Y. treculeana）叶绿体基因组序列,结合丝兰属现已发表的叶绿体基因组,使用生物信息学方法对6种丝兰属植物叶绿体全基因组进行基本结构、重复序列、边界收缩与扩张以及序列变异分析等在内的比较基因组学研究,并进行系统发育分析。结果表明：6种丝兰属植物叶绿体基因组大小、基因的类型及数目相近,种间基因组结构比较保守;从丝兰属植物叶绿体基因组中检测到多条重复序列,其中SSR位点多是由单核苷酸、双核苷酸和四核苷酸组成,且偏好使用A、T碱基;根据核酸多态性指数π≥0.008,在6种丝兰属植物叶绿体基因组中筛选出了psbK-psbl-trnS-GCU、rpl20-rps12和ccsA-ndhD 3个高变异区域;基于叶绿体全基因组和LSC+SSC区序列构建的系统发育关系基本一致,确定了6种丝兰属植物间的系统发育关系,其中无刺龙舌兰与克雷塔罗丝兰（Y. queretaroensis）的亲缘关系最近。本研究测序获得了无刺龙舌兰叶绿体基因组,揭示了6种丝兰属植物叶绿体基因组特征和序列变异情况,明确了各物种间的亲缘关系,研究结果可为后续丝兰属植物分子标记开发及系统发育研究提供参考。     

应用RAMP分子标记探讨拟鹅观草属的种间关系

采用RAMP (random amplified microsatellite polymorphism) 标记技术, 分析了拟鹅观草属9种1亚种和鹅观草属6 种植物之间的遗传变异和亲缘关系。33 个引物组合产生的310 条DNA扩增片段中, 286条(92 25%) 具有多态性, 每个引物组合产生5~13条多态性带, 平均为8 67条。利用310个RAMP标记, 在NTSYS pc软件中, 计算Jaccard遗传相似系数, 建立UPGMA聚类图。结果表明: (1) 物种间遗传差异明显, 具有丰富的遗传多样性; (2) 阿拉善鹅观草和大丛鹅观草与拟鹅观草属的物种聚类在一起, 表明它们与拟鹅观草属的亲缘关系较近, 而与本试验所分析的另外4个鹅观草属物种的亲缘关系较远; (3) RAMP分子标记可以将拟鹅观草属的物种分开, 而且形态相似、地理分布相同或相近的物种聚类在一起;(4) RAMP结果与形态学和细胞学的分析结果一致, 表明RAMP标记是评价拟鹅观草属种间关系十分有效的方法。     

玉米SSR引物在芒属植物遗传多样性分析的应用研究

目的:本文为了探索芒属植物的遗传多样性,方法:运用SSR分子标记的方法,用30对玉米SSR引物对15份中国湖南省的野生芒属材料进行扩增.结果:结果表明:30对引物共扩增出159条带,其中多态性条带121个,占76.10%.平均Nei's基因多样度为0.1992,平均Shannon信息指数为0.3139.UPGMA聚类分析显示,15份材料在遗传相似系数(GS)为0.75水平上,聚成三大类.第一大类由芒组成,第二大类由五节芒组成,第三大类由南获组成.这与形态学上的分类吻合.结论:玉米的SSR引物对于芒属植物遗传多样性分析仍具有很好的可行性.     

应用RAMP标记分析国产姜黄属植物的遗传多样性

本研究运用RAMP(random amplified microsatellite polymorphism)分子标记分析了10种国产姜黄属(Curcuma)植物的遗传变异和亲缘关系。结果得到520条迁移率不同的条带,其中多态性条带有509条,每条引物平均得到10.6条带和10.4条多态性带,多态性条带的百分率为97.88%。69份供试材料之间遗传相似系数最大值为0.921,最小值为0.550。当遗传距离是0.61时,可将其分为四大类群。研究结果表明种间关系与地理位置有一定的关系,同时证实了姜黄属植物种质资源遗传多样性丰富,为姜黄属植物的分类鉴定奠定了基础。     

基于SSR分子标记分析云南月季种质资源亲缘关系(英文)

利用简单重复序列SSR(simple sequence repeat)标记技术对48份月季种质资源(包括14份野生种、20份古老月季品种和14份栽培品种)的遗传多样性和亲缘关系进行了分析.结果表明,(1)18对SSR引物在18个SSR位点上共检测到160个等位基因,每一位点的等位基因变幅为6～13个,平均8.9个,材料间遗传相似系数变化范围为0.157 8～0.754 9,表明在分子水平上云南月季种质资源具有丰富的遗传多样性.(2)聚类分析结果显示,在相似系数为0.44处,可将 14个野生种明显分为6个组,这与植物形态学分类结果上基本一致;在遗传相似系数为0.40水平上将48份供试材料分为八大组群.(3)亲缘关系分析结果显示,5个野生种和所有古老月季品种与大多数栽培品种的亲缘关系较近.     

内蒙古3种生态型扁蓿豆遗传多样性与亲缘关系的分析

采用SSR分子标记结合21个表型性状对来自内蒙古3种生态型扁蓿豆种质资源的遗传多样性和亲缘关系进行了分析.结果表明:3种生态型的22份扁蓿豆材料在考察的4个质量性状上差异明显;在17个数量性状上,总体变异程度为黄花型扁蓿豆>扁蓿豆>细叶扁蓿豆;表型性状的遗传相似系数在31.59～113.27间,变异系数为43.30%.SSR分析结果显示,18对引物平均多态性比率为80.09%,引物平均等位位点数为6.06,位点多态性信息含量平均为0.32,遗传相似系数在0.37～0.47间,变异系数为61.80%.表型性状聚类、SSR分子标记聚类及主成分分析结果均显示,黄花型扁蓿豆和扁蓿豆的亲缘关系较近,与细叶扁蓿豆的亲缘关系较远.     

SSR标记在毛木耳种质资源遗传多样性研究中的应用

本研究利用基于毛木耳全基因组开发的SSR标记对27份毛木耳菌株（野生14株、栽培13株）的遗传多样性进行分析。首先随机选取3个菌株（2个野生菌株、1个栽培菌株）的DNA为模板,从144对SSR引物中筛选出扩增条带清晰、稳定性强、多态性丰富的引物24对。24对SSR引物共检测到116个多态性SSR片段,每对引物的多态性片段有3-7个,引物平均检测效率为4.83个,Shannon’s遗传多样性指数范围是0.866-1.885,多态性位点比率100%。供试菌株遗传相似系数范围是0.618-0.971,说明毛木耳种质资源具有丰富的遗传多样性。野生菌株与栽培菌株间平均遗传相似系数分别为0.746、0.779,说明毛木耳野生菌株遗传多样性更为丰富。经聚类分析,在遗传相似系数为0.680时,可将供试菌株分为无色（白色）类群Ⅰ和有色（浅黄色到红褐色）类群Ⅱ。遗传相似系数为0.704时,可将供试菌株中栽培菌株和野生菌株明显区分（14株野生菌株均在类群Ⅱ-2中,13株栽培菌株分别在类群Ⅰ和Ⅱ-1中）。本研究表明基于全基因组的SSR标记能从分子水平上揭示各菌株间的遗传差异,丰富毛木耳遗传多样性的研究手段,并为进一步进行毛木耳的品种选育、遗传学研究等提供有力手段。     

Analysis of genetic relationship on Amygdalus mira (koehne) Ricker with other peach species using simple sequence repeat (SSR)

Amygdalus mira (Koehne) Ricker is native to China and has many good economical traits. However, its genetic diversity information has not been extensively studied. In this study, to assess the genetic diversity and relationships of A. mira and other peach species (nineteen accessions from Zhengzhou, Henan Province and seven accessions from Harbin) we used simple sequence repeat (SSR) markers. Here, 10 SSR primers were used, and 100% of the SSR primers were polymorphic, with an average of 5.5 alleles per primer pairs, suggesting that these primers were informative for this study. Additionally, polymorphism information content (PIC) value ranged from 0.82 to 0.96 with an average of 0.91. All the accessions were clustered into two groups (cluster 1 and cluster 2) based on SSR data. Principal coordinate analysis recovered similar results that all accessions were divided into two major clusters. The genetic variations within and among populations were 63.9% and 36.1%, respectively. In conclusion, A. mira maintains high genetic variation levels. This research will be potentially useful to aid breeding and enhance the economic and ornamental value of this wild peach.     

基于遗传多样性构建金针菇的核心种质群体及分子身份证

金针菇Flammulina filiformis是我国产量最高的工厂化栽培食用菌。为提高优良工厂化栽培金针菇种质的育种效率,本研究以国内外收集的105份金针菇种质为材料,开展体细胞不亲和评价,并采用SSR分子标记的方法对所有种质进行遗传多样性分析和聚类分析。20对SSR引物在105份种质中共扩增得到209个等位基因位点,所有种质间的遗传相似系数为0.71-1.00,在遗传距离0.76处可分为5个大类群。105份金针菇种质共包含67种不同的遗传背景,野生金针菇种质比栽培种质具有更丰富的遗传多样性。基于SSR的聚类分析结果和体细胞不亲和评价结果既相互印证,又可互为借鉴。本研究构建了包含44份金针菇种质的核心种质群体,占所有供试材料的41.90%,保留了100%等位基因。核心种质群体覆盖区域广泛,最大限度地保留了原始群体的遗传多样性和表型变异,可为育种的亲本选择提供参考。进一步构建了能同时反映每份金针菇种质SSR分子标记指纹图谱、收集地区、子实体颜色和栽培性状的分子身份证编码,并转换成可视二维码,为金针菇种质的高效标识和快速溯源提供了科学依据。     

DNA barcodes and microsatellites: How they complement for species identification in the complex genus Tamarix (Tamaricaceae)

DNA barcoding allows the identification of an organism by comparing the sequence of selected DNA regions (barcodes) with a previously compiled database, and it can be useful for taxonomic identification of species in complex genera, such as Tamarix. Many species of this genus show convergent morphology, which leads to frequent errors in their identification. Highly variable genetic markers, such as microsatellites or short sequence repeats (SSR), could be used to differentiate species where DNA barcodes fail. Here, we tested the ability of both, 5 different marker regions (rbcL, matK, ITS, trnH-psbA, and ycf1), and 14 microsatellites, to properly identify Tamarix species, especially those from the Mediterranean Basin, and compared the pros and cons of the different analytical methods for species identification. DNA barcoding allows the genetic identification of certain species in Tamarix. The two-locus barcodes matK + ITS and ITS + ycf1 were the best-performing combinations, allowing up to 69% and 70%, respectively, correct identification. However, DNA barcoding failed in phylogenetically close groups, such as many Mediterranean species. The use of SSR can aid the identification of species, and the combination of both types of data (DNA barcoding and SSR) improved the success. The combination of data was especially relevant in detecting the presence of hybridization processes, which are common in the genus. However, caution must be exercised when choosing the clustering methods for the SSR datasince different methods can lead to very different results.     

Development of mapped simple sequence repeat markers from common bean (Phaseolus vulgaris L.) based on genome sequences of a Chinese landrace and diversity evaluation

Microsatellite or single sequence repeat (SSR) markers have been commonly used in genetic research in many crop species, including common bean (Phaseolus vulgaris L.). A limited number of existing SSR markers have been designed from high-throughput sequencing of the genome, warranting the exploitation of new SSR markers from genomic regions. In this paper, we sequenced total DNA from the genotype Hong Yundou with a 454-FLX pyrosequencer and found numerous SSR loci. Based on these, a large number of SSR markers were developed and 90 genomic-SSR markers with clear bands were tested for mapping and diversity detection. The new SSR markers proved to be highly polymorphic for molecular polymorphism, with an average polymorphism information content value of 0.44 in 131 Chinese genotypes and breeding lines, effective for distinguishing Andean and Mesoamerican genotypes. In addition, we integrated 85 primers of the 90 polymorphism markers into the bean map using an F2 segregating population derived from Hong Yundou crossed with Jingdou. The distribution of SSR markers among 11 chromosomes was not random and tended to cluster on the linkage map, with 14 new markers mapped on chromosome Pv01, whereas only four loci were located on chromosome Pv04. Overall, these new markers have potential for genetic mapping, genetic diversity studies and map-based cloning in common bean.     

Deciphering the global phylogeography of a coastal shrub (Scaevola taccada) reveals the influence of multiple forces on contemporary population structure

The phylogeography of coastal plant species is heavily influenced by past sealevel fluctuations, dispersal barriers, and life-history traits, such as long-distance dispersal ability of the propagules. Unlike the widely studied mangroves, phylogeographic patterns have remained mostly obscure for other coastal plant species. In this study, we sampled 42 populations of Scaevola taccada (Gaertn.) Roxb., a coastal shrub of the family Goodeniaceae, from 17 countries across its distribution range. We used five chloroplast DNA (cpDNA) and 14 nuclear microsatellite (simple sequence repeat [SSR]) markers to assess the influence of abiotic factors and population genetic processes on the phylogeographic pattern of the species. Geographical distribution of cpDNA haplotypes suggests that the species originated in Australia, followed by historical dispersal and expansion of its geographic range. Multiple abiotic factors, including the sealevel changes during the Pleistocene, the presence of landmasses like the Malay Peninsula, and contemporary oceanic circulation patterns, restricted gene flow between geographically distinct populations, thereby creating low haplotype diversity and a strong population structure. Population genetic processes acted on these isolated populations, leading to high nuclear genetic diversity and population differentiation, as revealed from analyzing the polymorphic SSR loci. Although genetic divergence was mostly concordant between cpDNA and SSR data, asymmetrical gene flow and ancestral polymorphism could explain the discordance in the detailed genetic structure. Overall, our findings indicate that abiotic factors and population genetic processes interactively influenced the evolutionary history and current phylogeographic pattern of S. taccada across its distribution range.     

Development and use of EST-SSR markers for assessing genetic diversity in the brown planthopper (Nilaparvata lugens Stål)

To assess genetic diversity in populations of the brown planthopper (Nilaparvata lugens St?l) (Homoptera: Delphacidae), we have developed and applied microsatellite, or simple sequence repeat (SSR), markers from expressed sequence tags (ESTs). We found that the brown planthopper clusters of ESTs were rich in SSRs with unique frequencies and distributions of SSR motifs. Three hundred and fifty-one EST-SSR markers were developed and yielded clear bands from samples of four brown planthopper populations. High cross-species transferability of these markers was detected in the closely related planthopper N. muiri. The newly developed EST-SSR markers provided sufficient resolution to distinguish within and among biotypes. Analyses based on SSR data revealed host resistance-based genetic differentiation among different brown planthopper populations; the genetic diversity of populations feeding on susceptible rice varieties was lower than that of populations feeding on resistant rice varieties. This is the first large-scale development of brown planthopper SSR markers, which will be useful for future molecular genetics and genomics studies of this serious agricultural pest.     

印度蔊菜与无瓣蔊菜形态变异特征的比较及分类关系

印度蔊菜(Rorippa indica)与无瓣蔊菜(R. dubia)的分类关系仍存在较大争议, 为阐明二者的分类学关系, 本研究综合利用形态指标测量、DNA相对含量检测、体细胞染色体观察和基于SSR分子标记的遗传距离分析等方法, 系统地比较了二者的分类学特征和细胞遗传学差异。结果表明: 印度蔊菜(2n = 48)为六倍体, 无瓣蔊菜(2n = 32)为四倍体。同时, 前者DNA相对含量约为150, 是后者的1.5倍。通过45对SSR分子标记的遗传距离分析得出, 相对于球果蔊菜(R. globosa)与欧亚蔊菜(R. sylvestris), 二者亲缘关系较近, 独立聚类为一支, 但在遗传距离为0.23处可以明确划分为两个种。同时, 利用角果长度和结籽密度两个形态指标可以将二者明显区分为两个种。另外, 二者存在明显的生殖障碍, 通过正反交授粉实验得出: 印度蔊菜与无瓣蔊菜自花授粉的结实率分别为97.73%和95.65%, 而以印度蔊菜为母本的杂交处理结实率为0, 以无瓣蔊菜为母本的杂交处理结实率为47.06%, 但其种子萌发率为0。综上所述, 印度蔊菜与无瓣蔊菜为两个种。     

基于SSR标记的琅琊山球孢白僵菌寄主专化性

球孢白僵菌Beauveria bassiana是一类常见的昆虫病原真菌,其自然侵染的寄主昆虫众多,达15目149科750种。为了解球孢白僵菌自然种群的遗传多样性,探讨种群异质性和寄主来源之间的关系,分析其寄主专化性的强弱,本研究利用SSR分子标记技术,比较了安徽琅琊山国家森林公园的85株球孢白僵菌（寄主种类涉及7目24种）群体遗传多样性差异,通过构建聚类树分析菌株基因型和寄主关联性。结果表明琅琊山球孢白僵菌群体Nei’s基因多样性指数h=0.2906,Shannon信息指数I_s=0.4510,多态位点百分率P为100%。不同寄主目球孢白僵菌遗传多样性水平由高至低为鞘翅目>膜翅目>同翅目>双翅目>鳞翅目>直翅目>半翅目,其中菌株数量较多的鞘翅目、膜翅目和同翅目3个亚种群的遗传多样性较高且水平接近。聚类分析发现8对SSR引物将85株球孢白僵菌分成29个基因型,并在遗传相似系数0.70处分别聚为3个分支。分析寄主类型发现相同基因型的株系可侵染不同目的寄主,而同一类型寄主也可被不同基因型的菌株侵染。球孢白僵菌种群的总体遗传多样性较高,遗传谱系与寄主来源无明显相关性,菌株的寄主专化性弱。     

Comparative Assessment of SSR and AFLP Markers for Evaluation of Genetic Diversity and Conservation of Fig, <Emphasis Type="Italic">Ficus carica</Emphasis> L., Genetic Resources in Tunisia

This study characterises the genetic variability of fig, Ficus carica L., using simple sequence repeat (SSR) and amplified fragment length polymorphism (AFLP) markers. It compares the efficiency and utility of the two techniques in detecting variation and establishing genetic relationships among Tunisian fig cultivars. Our results show that using both marker systems, the Tunisian fig germ plasm is characterised by having a large genetic diversity at the deoxyribonucleic acid level, as most of AFLP bands were detected and all SSR markers were polymorphic. In fact, 351 (342 polymorphic) and 57 (57 polymorphic) bands were detected using AFLP and SSR primers, respectively. SSR markers were the most polymorphic with an average polymorphic information content value of 0.94, while AFLP markers showed the highest effective multiplex ratio (56.9) and marker index (45.2). The effective marker index was recorded highest (4.19) for AFLP markers and lowest (0.70) for the SSR ones. Our results demonstrate that (1) independent as well as combined analyses of cluster analyses of SSR and AFLP fragments showed that cultivars are clustered independently from their geographical origin, horticultural classifications and tree sex; (2) the analysis of molecular variance allowed the partitioning of genetic variation within and among fig groups and showed greater variation within groups and (3) AFLP and SSR markers datasets showed positive correlation. This study suggests the SSR and AFLP markers are suitable for diversity analysis and cultivars fingerprinting. An understanding of the genetic diversity and population structure of F. carica in Tunisia can also provide insight into the conservation and management of this species.