12个地方鸡种遗传多态性的AFLP指纹分析

利用6对AFLP引物组合对中国12个地方鸡种进行了遗传检测，构建了各个品种的AFLP DNA指纹图谱，根据AFLP分析结果, 统计了每个引物组合在各个品种中检测到的多态性条带和特异性条带，计算了12个地方鸡种的遗传相似系数和遗传距离，并据此构建了UPGMA聚类关系图，分析了所研究鸡种的遗传关系。结果表明：6对AFLP引物组合在12个地方鸡种中共检测到279条多态性条带，平均每个引物组合产生46.5条多态性标记，同时在每个品种群体中还检测到了数量不等的特异性条带，其中寿光鸡和东乡黑鸡最多，为9条，旧院黑鸡和兴义矮脚鸡最少，为1条。12 个鸡种聚为3类，鸡种间的遗传相似系数及聚类结果与所保存的地方鸡种的地理分布、现实状况是相吻合的。从而表明AFLP指纹用于我国地方鸡种遗传多态性分析、品种的鉴定及品种间的亲缘关系分析是可行的。     

利用小麦SSR标记分析鸭茅种质资源的遗传多样性

使用小麦(Triticum aestivum)SSR引物和扩增程序,以中国春小麦(T. aestivum)品种为对照,利用SSR标记对来自国内外的45份鸭茅(Dactylis glomerata L.)种质资源进行遗传多样性研究.结果表明,20对引物扩增出295个条带,多态性条带为187条,多态性条带比率为61.15%,鸭茅种质资源的遗传相似系数范围为0.7848～0.9513.聚类分析和主成分分析将供试材料分为6大类,聚类结果不仅能反映鸭茅生态适应性特征与其生长发育状况及生产性能相关,还显示出国产鸭茅品种遗传基础较为狭窄.研究表明将小麦SSR引物用于检测鸭茅遗传多样性行之有效.     

基于SSR标记的梨资源遗传多样性分析

本研究利用SSR标记技术对56份梨资源进行了遗传多样性分析。利用筛选出的6对SSR引物共扩增40条谱带,其中多态性位点38个,多态性位点比例为95%,每对引物产生有效等位基因6.3个。各位点期望杂合度H值在0.0354～0.491,平均为0.1964;有效等位基因Ne值在1.0367～1.9648,平均值为1.2958;香农指数I值平均值为0.3256,说明了供试梨材料的遗传多样性较低。利用SSR标记可将44个栽培品种区分开,但无法区分芽变和原种。根据SSR标记揭示的多态性,采用NTSYS-pc软件,以UPGMA法进行聚类分析,结果显示所检测的56份梨材料在相似系数0.71处可分为4组,其中中国的白梨、秋子梨和砂梨相互交错在一起,没有独自各自成组。     

白菜类蔬菜遗传多样性的AFLP分子标记研究

首次对白菜（Brassica rapa)类蔬菜的遗传多样性和分类进行了AFLP分子标记研究。共采用了137份材料，从64对引物组合中选择了4对扩增条带多，多态检出率高的3＋3引物组合，检测了210个位点，并对AFLP数据进行了聚类分析，结果表明，芜菁和白菜类蔬菜各自单独聚为一类，它们的亲缘关系较远。在白菜类蔬菜当中，所有大白菜和薹菜聚为一类，它们是比较特殊的类群，且亲缘关系密切，小白菜的聚类结果与其园艺学分类差别较大。小白菜各类型间的相似性程度较低，说明小白菜的起源较大白菜要早。大白菜的聚类表明，大白菜现有品种的遗传多样性较为狭窄。     

广西地方食用木薯种质资源遗传多样性分析

为研究广西地方食用木薯材料的遗传多样性,以48份广西地方食用木薯为试验材料,分析其变异系数、遗传多样指数、聚类分析、多态性和遗传相似性系数。结果表明,收集的木薯材料的平均表型变异系数为37.9%,平均遗传多样性指数为0.807,其中主茎分叉角度的变异系数最大,为86.7%,块根内皮颜色的遗传多样性指数最大,为1.842。13对SSR引物共扩增出118个条带,其中多态性条带为106个,多态性比率为86.23%;分子标记聚类结果发现,遗传相似性系数在0.415~1.000之间;通过对比发现表型聚类和分子聚类结果不一致,其中表型聚类发现类群划分与地理来源之间没有关联,但与株型性状有一定的关联;在遗传相似系数为0.62时,SSR分子标记聚类为两类材料,第一类材料地理分布无规律,第二类材料大多分布在桂南。本研究结果表明,广西地方食用木薯资源遗传多样性具有一定的丰富度,可为创制优异食用木薯种质资源和新品种选育奠定基础。     

应用RAPD技术研究4种鲍的亲缘关系

应用RAPD技术研究 4种鲍的亲缘关系结果表明 ,4种鲍群体中 2 0个有效引物共扩增出 5 38条DNA带 ,平均每个引物扩增的条带数为 2 6 .9;扩增的多态性条带数 136 ,平均每个引物扩增的多态性条带数为 6 .8;多态位点百分数为 2 5 .3%。盘鲍群体和皱纹盘鲍群体之间遗传距离与遗传一致度分别为 0 .2 8和 0 .72 ,杂色鲍群体和九孔鲍群体之间遗传距离与遗传一致度分别为 0 .32和 0 .6 8。聚类分析把盘鲍群体和皱纹盘鲍群体聚为 1组 ,二者亲缘关系较近 ;杂色鲍群体和九孔鲍群体聚为 1组 ,二者亲缘关系也较近     

SSR和SRAP标记研究油菜杂交种骨干亲本的遗传多样性

用SSR和SRAP两种分子标记方法研究51份甘蓝型油菜杂交种亲本系的遗传多样性,并对两种分子标记研究结果进行比较。结果发现,在51份材料中,45对SSR引物共扩增出194条多态性条带,平均每对引物为4.3条,25对SRAP引物共扩增出197条多态性条带,平均每对引物为7.9条。UPGMA聚类分析表明,SSR和SRAP标记都可将51份亲本材料划分为五大类群,本所选育的玻里马细胞质雄性不育系（Polima CMS）的主要保持系和恢复系都聚在同一类群的不同亚群中。根据系谱资料分析发现,SRAP标记划分的类群与系谱资料更为接近,SRAP标记更适用于遗传关系较近材料的遗传多样性分析。SRAP标记揭示的亲本间遗传距离要大于SSR标记揭示的遗传距离。两种不同标记方法揭示出油菜亲本遗传多样性的差异主要是由不同的标记方法揭示的标记位点等位基因变异数不同造成的。     

利用SSR技术构建多花黑麦草品种指纹图谱

通过构建我国多花黑麦草主栽品种的SSR标记指纹图谱数据库,以实现对多花黑麦草品种的快速、准确鉴定.本研究利用SSR标记,基于多态性高、稳定性强和连锁群分布均匀的原则,从100对多花黑麦草(Lolium multiflorum Lam.)基因组来源的SSR引物中,筛选出12对引物用来构建了21个多花黑麦草品种(系)的指纹图谱.12对SSR引物共扩增出108种多态性基因型,多态性比率达94.15％,每对引物的基因型从5～22种不等,平均每对引物扩增出9种基因型,多态性信息量(PIC)变幅为0.744～0.934,平均为0.843,此12对引物可以在构建多花黑麦草品种DNA指纹数据库作为核心引物推荐使用.21个多花黑麦草品种(系)基因型间遗传相似性系数在0.4956～0.8571之间,UPGMA聚类分析表明,在相似系数0.69处可将全部材料分为3大类.7对引物在9个品种上具有唯一特征带,采用15-08C单对引物即可将21个多花黑麦草品种完全区分开,该对引物不仅多态性高(PIC=0.934),且具备多个品种的特征谱带.基于该引物建立了供试品种指纹图谱标准模式图,每个品种具有唯一的指纹图谱(带型),为牧草品种的审定和保护以及选配优良杂交组合培育新品种提供了重要的理论依据.     

大豆种质资源RAPD标记遗传多样性研究

为深入研究并充分利用野生大豆资源,本文利用RAPD分子标记对40份大豆材料加以分析,旨在从DNA分子水平上探索野生大豆、地方品种和育成品种之间的遗传多样性状况。结果表明:50个RAPD引物筛选出具有多态性且扩增条带清晰的引物38个,共检测出407条带,其中多态谱带309条,多态性程度为75.92%。每个引物可扩增出2～14条多态性带,平均产生多态性谱带8.1条;平均多样性指数为2.3377,变幅范围为0.5865～4.2133。遗传相似系数变幅范围为0.44～0.92,平均为0.75。野生大豆的多态比例(94.35%)、多样性指数(2.2336)分别高于育成品种(87.47%、1.7331)和地方品种(83.54%、1.6198)。遗传相似系数为野生大豆(0.6498)地方品种(0.7015)育成品种(0.7177),育成品种与地方品种间为0.6599,育成品种与野生大豆间为0.6487,地方品种与野生大豆间为0.6045。UPGMA聚类分析结果表明,40份大豆材料聚为6类,育成品种和地方品种各自聚为一类,野生大豆聚为4类。野生大豆特异等位基因数远远高于育成品种和地方品种二者的相加之和。本研究从分子水平上揭示了野生大豆与栽培大豆区别明显,宜作为一个独立的种,同时野生大豆变异幅度大,遗传基础广,是大豆育种实践中的优良基因资源。     

47份水稻品种资源的ISSR遗传多样性分析

为研究广东省惠州市种植的常规水稻品种的遗传多样性,本实验利用ISSR标记对47份水稻品种资源进行遗传多样性检测。从49条引物中筛选出5条重复性好,条带清晰的引物进行PCR扩增,共扩增出53条带,每个引物可以扩增出9～13条带,平均为10．6条,其中47条具有多态性,比率为88．7％。不同水稻品种间遗传相似系数变幅为0．319～0．936,平均达0．691,说明ISSR标记能够揭示材料间较高的遗传多样性。通过聚类,从分子水平对水稻品种资源的遗传关系进行分析,并对47份水稻品种资源进行分类,ISSR标记能将47份水稻品种完全区分开,为水稻品种资源的研究利用提供参考。     

云南杂交玉米SSR标记核心引物的筛选及多样性分析

为降低合成引物成本,加快杂交玉米品种鉴定进程,筛选适用于云南玉米杂交种SSR标记鉴定的核心引物。本研究用玉米SSR标记鉴定规程中推荐的40对SSR引物对12个杂交玉米品种DNA进行扩增,筛选出多态性高、扩增效果好、稳定性好的20对引物,推荐其作为云南玉米杂交种特异性鉴定的核心引物。并用筛选的核心引物对云南220个杂交玉米材料进行多样性分析及评价。筛选的20对SSR引物在12个杂交玉米品种中共检测到216个等位变异,平均每对引物检测到10.80个。20对SSR核心引物在220个杂交玉米材料中共检测到236个等位变异,平均每对引物检测到11.80个;平均有效等位变异为3.158 8;平均Shannon-Weaver多样性信息指数为3.028 2。聚类分析表明,220个杂交玉米材料间的相似系数为0.62~0.95。以0.62为阈值可将220个杂交玉米材料划分为两大类群,第Ⅰ类群包括10个玉米材料,占4.5%;第Ⅱ类群包括210个玉米材料,占95.5%。本研究筛选的20对SSR引物多态性高、扩增效果好、稳定性好,可作为云南玉米杂交种特异性鉴定的核心引物。     

Analysis of genetic diversity in Indian robusta coffee genepool (<Emphasis Type="Italic">Coffea canephora</Emphasis>) in comparison with a representative core collection using SSRs and AFLPs

Genetic diversity among 40 accessions (Coffea canephora) of robusta coffee genepool available in India was determined in comparison with 14 representative samples from a C. canephora core collection and three accessions of C. congensis, using amplified fragment length polymorphism (AFLP) and simple sequence repeats (SSR) markers. Both these molecular approaches were able to generate unique fingerprints for each of the accessions analysed. All the 12 SSR primers used in the present study were found polymorphic, with an average of six alleles per primer pair. Comparative analysis revealed the higher amount of diversity in representatives from a core collection than in the Indian genepool. Moreover, a total of 205 polymorphic AFLP bands were scored in all the 57 accessions analysed. The genetic relationship among 57 accessions was compared on the basis of SSR and AFLP polymorphisms. Genetic similarity dendrograms showed high correlation between the two marker systems. This study clearly established the high amount of diversity present in core samples, which is not represented in Indian genepool. Furthermore, the three accessions of C. congensis did not exhibit any significant diversity from other robusta accessions supporting the school of thought that C. congensis forms a biotype of C. canephora. The potential use of SSRs and AFLP markers in genetic diversity analysis for better ex situ management and also for exploitation of diversity in breeding programmes is discussed.     

Assessment of genetic relationships in durum wheat cultivars using AFLP markers

The genetic relationships were assessed for the first time in Turkish durum wheat cultivars using AFLP markers. In the analysis, 18 AFLP primer combinations resulted in a total of 189 polymorphic loci. All of the selective primers used are Eco and Mse primers with three nucleotide extentions on the 3 ends. The number of polymorphic markers per primer combination ranged from 4 to 24. The relationships, among nine winter and six spring type durum wheat cultivars, obtained with various algorithms are in accordance with the known pedigree information of the cultivars. Based on `Nei72' genetic distance analysis, the most distant two cultivars are `Berkmen-469' (winter type) and `Diyarbakìr-88' (spring type), and the closest two are `Selçuklu-97' and `Sofu', with the values of 0.793 and 0.115, respectively. The closest two winter type cultivars are `Akbasak-073-44' and `Kunduru-414-44' (0.128).     

Assessment of genetic relationships among Pyrus species and cultivars using AFLP and RAPD markers

Twenty-five Pyrus communis L. cultivars including eight traditional Portuguese pears, and four commercial Pyrus pyrifolia (Burm.) Nak. (Japanese pear or `nashi') cultivars were analysed by RAPD and AFLP techniques focusing on their molecular discrimination and the assessment of their genetic relatedness. Twenty-five primers generated 324 RAPD markers, among which 271 (84%) were polymorphic. The AFLP technique, using seven primer combinations, revealed a similar level of molecular polymorphisms (87%), representing 418 polymorphic bands among a total of 478 scored in autoradiographs. The high reproducibility of RAPD and AFLP techniques was confirmed comparing DNA samples from different extractions and different digestions of DNA from the same plant. Three genetic similarity matrices and respective dendrograms were elaborated on using RAPD, AFLP or joint RAPD and AFLP data. Both molecular marker techniques proved their reliability to assess genetic relationships among pear cultivars. P. pyrifolia cultivars exhibit a closer genetic relatedness, clustering apart from P. communis cultivars. Within P. communis, `William's', as well as `Doyenne du Comice', cluster close to their hybrids. Most of the Portuguese cultivars tend to cluster together, indicating to constitute a relatively independent genetic pool, which can be of interest in pear breeding programs.     

玫瑰黄链霉菌Men-myco-93-63与其突变株间的DNA多态性分析和序列特征性扩增区域(SCAR)标记

玫瑰黄链霉菌(Streptomyces roseoflavus )Men-myco-93-63是分离自马铃薯疮痂病自然衰退土壤中的一株拮抗菌。前期研究表明,该菌株及其发酵液对棉花黄萎病菌（Verticillium dahliae）等多种重要的植物病原真菌具有较强的抑制作用。利用AFLP对Men-myco-93-63及其8株抗生素生物合成阻断突变株进行了基因组DNA多态性分析。结果表明,38对AFLP引物共产生3 142条谱带,其中2 362条为多态性谱带,占总带数的75.2 %。从96对引物中筛选得到了3对引物：E-CA/M-GA,E-GA/M-AC和E-GA/M-AG,分别扩增出254、312和209 bp 3条仅在Men-myco-93-63中存在,命名为EM254、EM312和EM209。将这3个片段回收、克隆和测序,成功地将其转化为SCAR标记,可以更加方便地用于对突变株的分子检测。     

甘蓝型油菜秦优10号杂交种纯度鉴定的SSR引物筛选

为了建立一套快速可靠的油菜杂交种纯度的鉴定方法,本文以秦优10号及其亲本、杂种ZZH2为试验材料,对前人开发的2对SSR引物（7号引物,9号引物）进行了再次筛选。结果显示,7号引物不但能很好地区别出混入杂交种中的亲本,还能将杂交种子的同母异父组合种子从杂交种中分离出来,能够用于鉴别秦优10号杂交种子的真伪;9号引物能区分出杂交种和母本,但不能区分开杂交种和父本。同时,本试验利用人工制成的秦优10号杂交种标准样（纯度为100%）以及7份大田鉴定不同纯度梯度的杂交种子对7号引物鉴定结果的准确性进行了验证,鉴定结果与大田鉴定结果基本一致。本文结果将为鉴定秦优10号杂交种纯度提供更准确的技术资料。     

甘蓝SSR标记在近缘种青花菜的通用性及其应用

本研究对50条甘蓝SSR引物在其近缘种青花菜中的通用性进行了分析,结果表明,38对引物在青花菜上可有效扩增,扩增产物分子量在100～1500bp,有效扩增比率为76%,其中18%具有较好的多态性,揭示了两种作物基因组间存在一定的相似性。同时利用获得的多态性较好的9对引物对青花菜进行基因型鉴定和遗传多样性分析,20份青花菜基因型中共检测到51个基因位点,平均每个引物组合可扩增出5.67个条带,多态性为66.7%。多引物组合可鉴别出所有青花菜基因型。聚类分析结果表明同一来源的基因型间具有相近的遗传基础,且聚类与熟性具有一定的相关性。本研究为今后青花菜种质资源的收集、利用及分子标记辅助育种提供了新的SSR标记和参考。     

玉米诱变系的SSR遗传变异分析

从97对SSR引物中筛选出52对扩增产物具有稳定多态性的引物,对基础材料玉米自交系"082"及其48个诱变系进行检测,共检测到170个等位基因变异,每对引物检测出2~6个等位基因,平均为3.27个;每个位点的多态性信息量(PIC)变化于0.039~0.715之间,平均为0.327;49个材料之间的遗传相似系数变化范围在0.377~1.000,平均为0.823。UPGMA聚类分析将49个材料分成6类,表明材料间存在着广泛的遗传差异。这些遗传变异与材料的品质性状、农艺性状相关。     

Analysis of genetic diversity in Tunisian durum wheat cultivars and related wild species by SSR and AFLP markers

Thirty-four durum wheat cultivars representing the Tunisian durum (Triticum durum Desf.) wheat collection and seven wild species of wheat relatives (Triticum turgidum L., T. dicoccon Schrank., T. dicoccoides (Körn) Schweinf., T. araraticum Jakubz., T. monococcum L., Aegilops geniculata Roth, and Aegilops ventricosa Tausch) were analysed with amplified fragment length polymorphism (AFLP) and microsatellite (SSR) markers. Both marker systems used were able to differentiate durum wheat cultivars from the wild relatives and to specifically fingerprint each of the genotypes studied. However, the two marker systems differed in the amount of detected polymorphisms. The 15 SSR markers were highly polymorphic across all the genotypes. The total number of amplified fragments was 156 and the number of alleles per locus ranged from 3 to 24 with an average of 10.4. Two SSR markers alone, Xwms47 and Xwms268, were sufficient to distinguish all 34 durum wheat genotypes. The five AFLP primer pair combinations analysed yielded a total of 293 bands, of which 31% were polymorphic. The highest polymorphic information content (PIC) value was observed for SSRs (0.68) while the highest marker index (MI) value was for AFLPs (7.16) reflecting the hypervariability of the first and the distinctive nature of the second system. For durum wheat cultivars, the genetic similarity values varied between 31.3 and 81% for AFLPs (with an average of 54.2%), and between 3.6 and 72.7% for SSRs (with an average of 19.9%). The rank correlation between the two marker systems was moderate, with r = 0.57, but highly significant. Based on SSR markers, highest genetic similarity (GS) values were observed within the modern cultivars (37.3%), while the old cultivars showed a low level of GS (19.9%). Moreover, the modern cultivars showed low PIC and MI values. UPGMA Cluster analysis based on the combined AFLP and SSR data separated the wild wheat species from the durum wheat cultivars. The modern cultivars were separated from the old cultivars and form a distinct group.