ICRISAT花生微核心种质青枯病抗性鉴定

对ICRISAT花生微核心种质155份材料进行抗青枯病鉴定,获得ICG9249和ICG12625两份抗青枯病材料,平均抗性达到了91.7%。与中国核心高抗5份种质共同作为材料,以SSR技术对其亲缘关系和遗传多样性进行了分析。在选用的58对SSR引物中,24对引物能扩增出稳定的多态性条带,这些引物能在抗青枯病花生种质基因组DNA中扩增出2~7个DNA片段。结果表明,7份抗青枯病种质的遗传距离为0.17~0.71,平均为0.49。其中ICG12625和撮豆、富川大花生的遗传距离最大（0.71）,嵊县小红毛和富川大花生的遗传距离最小（0.17）。经过统计,两两品种之间遗传距离达0.50以上的有12个组合,说明了这些抗青枯病种质资源的遗传多样性。根据DNA扩增结果,绘制了抗青枯病种质的指纹图谱,明确了其SSR分子特性。通过聚类分析结果和植物学性状调查结果显示,ICG12625与其它种质距离较远,且具有优良的植物学性状,可以作为疏枝亚种的亲本材料加以研究利用。     

利用核心种质发挥及评价花生抗黄曲霉资源

黄曲霉菌极大地限制全世界的花生生产和产业发展,且生产上抗性品种较少,我国花生育种和生产中的抗性资源缺乏,迫切需要发掘抗黄曲霉菌种质。本研究以中国花生核心种质561份和ICRISAT微核心种质155份,鉴定了黄曲霉侵染和产毒抗性,发掘出抗黄曲霉侵染和产毒种质各8份,包括具优良农艺性状的抗黄曲霉产毒种质51002-6。鉴定结果表明,ICRISAT花生微核心种质中抗黄曲霉侵染和产毒种质的频率高于中国花生核心种质;普通型花生资源中抗黄曲霉侵染种质的频率较高,龙生型资源中抗黄曲霉产毒种质的频率较高。根据SSR分析,鉴定出与生产上推广应用的优良品种中花5号、中花6号、中花12和远杂9102遗传距离较远的抗黄曲霉产毒种质ICG12625和抗侵染种质ICG4750,拓宽了我国花生品种改良的遗传基础。根据抗病基因产物的NBS类型保守域设计简并引物对抗黄曲霉种质的DNA进行PCR扩增、克隆、测序和分析,获得了1条RGA片段。     

中国花生核心种质的建立及与ICRISAT花生微核心种质的比较

以中国花生种质资源数据库中记录的6 390份花生资源为材料, 以其基本数据、特征数据和评价数据为信息, 采用分层分组聚类以及随机取样与必选资源相结合的方法, 构建了由576份资源组成的花生核心种质, 占基础收集品的9.01%。除出仁率外, 核心种质与基础收集品种间的其他14个性状平均值和多样性指数差异均不明显, 表明本研究建立的核心种质是有效的。与ICRISAT花生微核心种质的比较, 中国花生资源在龙生型和珍珠豆型方面具有优势, 叶片长、叶片宽、种子长、种子宽的遗传多样性丰富; 而ICRISAT花生资源在多粒型和普通型方面具有优势, 且植株高度和总分枝数的遗传多样性比中国花生资源丰富。     

应用SRAP标记分析黑芝麻核心种质遗传多样性

利用SRAP分子标记技术对中国芝麻资源核心收集品中的黑芝麻种质进行遗传多样性分析。结果表明,13对引物组合对100份黑芝麻核心种质共扩增出稳定清晰的条带182条,其中多态性条带126条,占69.2%,每对引物组合的条带数和多态性带数分别为14.0个和9.7个;供试材料间成对遗传相似系数介于0.469~0.986,平均为0.726,通过UPGMA法,在遗传相似系数为0.68处可将供试材料聚为5个类群,表明黑芝麻核心种质具有较丰富的遗传多样性,聚类结果与地理分布没有明显的关系;遗传多样性指数是南方黑芝麻核心种质(0.3557)＞中部种质(0.3415)＞北方种质(0.2986)。本研究结果较全面反映了中国保存的黑芝麻种质资源遗传多样性特点,为我国黑芝麻资源进一步考察收集和引进,以及优异黑芝麻基因资源挖掘和育种利用提供了理论依据。     

黄麻核心种质的遴选

遴选黄麻核心种质可为黄麻种质创新及新品种选育奠定基础。本研究以300份黄麻种质资源为基础,基于SSR分子标记和农艺性状考察,结合地理来源构建核心种质。结果表明,11个农艺性状变异系数变幅在13.06%～84.87%,表现出丰富的遗传多样性。按农艺性状聚类分析可划分为8个类群,按分子标记聚类可划分为10个类群。结合2个聚类分析、地理位置并按比例取样,建立一个由108份品种(系)组成的预选核心种质。采用44对SSR引物对其进行遗传差异分析,在遗传相似系数为0.65时,可把108份品种(系)分成圆果种和长果种两大类。根据遗传差异分析,剔除遗传相似系数大于或等于0.85的遗传冗余,获得84份品种(系)的核心种质,其中圆果种60份和长果种24份。比较84份核心种质与300份种质的农艺性状变异系数及Shannon-Wiener指数发现,两者之间相差不大,表明遴选的84份核心种质可以最大限度代表300份黄麻种质资源的遗传多样性加以利用和保存。     

青萝卜种质遗传多样性分析与指纹图谱构建

采用SSR分子标记对青萝卜种质资源进行遗传多样性分析和指纹图谱构建能够为其合理保护和高效利用提供重要技术手段。本研究采用100对萝卜SSR引物对38份青萝卜种质进行PCR扩增,筛选出12对条带清晰、重复性好、多态性高的引物,平均每对引物扩增出来的条带数目为2.25条,多态性条带的比率为100%。使用Popgene 1.32软件计算出38份青萝卜种质的平均有效等位基因数(Ne)为1.642 7,Nei’s基因多样性指数(H)平均值为0.372 1,Shannon信息指数平均值(I)为0.550 2,结果表明这些青萝卜种质资源具有较丰富的遗传多样性。采用NTSYS 2.10e软件计算出38份青萝卜种质的遗传相似系数范围为0.240～0.963,基于遗传相似系数进行UPGMA聚类,在相似系数为0.61处,可将38份青萝卜种质分为三大类。利用12对引物为38份青萝卜种质构建的DNA指纹图谱具有唯一性,能够有效区分每份种质。该研究可为青萝卜的种质资源鉴定、杂交种选育等提供理论依据。     

国内外蚕豆核心种质SSR遗传多样性对比及微核心种质构建

运用24对SSR引物, 对国内外1075份初级地理蚕豆核心种质的遗传多样性分析显示, 等位变异数、有效等位变异数及Shannon’s信息指数分别为8.54、2.26和1.02;对全部参试资源进行聚类分析, 没有发现明显的群体结构, 表明初级地理核心种质的代表性较好, 遗传背景较广泛。之后采用每个类内随机抽样的方法构建含有129份国内资源和63份国外资源的蚕豆微核心种质, 等位基因变异数、有效等位变异数和Shannon’s信息指数的保留比例分别为87.32%, 101.26%, 101.82%;经t检验得出微核心种质与全部参试资源群体间遗传多样性差异不显著, 表明构建的微核心种质的遗传多样性可以代表初级地理蚕豆核心种质。     

中国石榴核心种质的初步构建

构建中国石榴的核心种质,对中国石榴种质资源的保存、研究和利用,具有重要意义。根据中国石榴135份总体种质的14个植物学、农艺学性状,采用Popgen Version 1.31软件,分析总体种质、初级核心种质以及8个不同产区石榴种质资源的遗传多样性。用SPSS 11.0 for Windows软件,以欧氏距离平方为系数,采用组间连接法,对总体种质进行系统聚类,采取系统取样和随机取样法,构建石榴初级核心种质。对不同产区初级核心种质、总体种质的香浓信息指数以及总体和初级核心种质性状的Nei基因多样性进行差异显著性测验,计算初级核心种质和总体种质性状的符合率,以检测初级核心种质构建效果。试验结果表明,135份总体种质的观察位点数是2-6、有效等位基因位点数为1.211-4.084、Nei基因多样性系数0.174-0.755、香浓信息指数0.317-1.511。选取41份资源构建了石榴初级核心种质。初级核心种质和总体种质遗传多样性t检验未达到显著水平。初级核心种质和总体种质14个性状均值、极差、标准差和变异系数的平均符合率分别为96.77%、95.1%、93.7%、92.1%,说明构建的核心种质能够代表全部种质资源的遗传多样性。     

马槟榔种质资源遗传多样性的RAPD分析

为了保护和开发中国野生马槟榔种质资源,利用RAPD技术对取自中国5个省的23份野生马槟榔种质进行遗传多样性分析。从100条RAPD随机引物中筛选出9条合适的引物,多态性条带比率(PPB)为91.35%,平均Shannon信息指数(I)为0.4205,平均Nei’s基因多样性(H)为0.2728,每位点平均有效等位基因数(NE)为1.4508。UPGMA聚类分析显示23份种质间的遗传相似系数(GS)范围为0.3846~0.9519,当相似系数为0.66时可分为3个类群。     

苏子种质资源的遗传多样性分析

为明确苏子种质资源亲缘关系,本研究以收集的44份苏子种质资源为材料,采用SSR、AFLP和SRAP分子标记对其进行遗传多样性和聚类分析.结果 表明,SSR、SRAP和AFLP引物的平均多态性分别为63.6％、85.2％和92.6％,44份种质间的遗传相似系数为0.717～0.967(平均为0.864);在遗传相似系数0...     

Population structure and linkage disequilibrium of ICRISAT foxtail millet (Setaria italica (L.) P. Beauv.) core collection

Use of diverse germplasm is a key factor which allows high level of resolution due to extensive recombination in the history. Therefore, population used in association mapping should posses as many phenotypes as possible. One of the methods to obtain most of the phenotypes is to construct the core collection. The ICRISAT foxtail millet core collection consisting of 155 accessions was genotyped using 72 simple sequence repeat (SSR) markers to investigate the genetic diversity, population structure and linkage disequilibrium (LD). A high degree of molecular diversity among the accessions was found, with an average of 16.69 alleles per locus. STRUCTURE analyses classify the accessions into four subpopulations (SP) based on SSR allelic diversity. The Neighbor joining clustering and the principal coordinate analysis were in accordance with the racial classification. The distribution of molecular genetic variation among and within the four SP and three races showed high degree of variability within each group, and low level of genetic distance (GD) among the groups. LD decay of <40 cM of GD in foxtail millet core collection was observed, which suggests that it could be possible to achieve resolution down to the 40 cM level. From this investigation, it is evident that the foxtail millet core collection developed at ICRISAT is very diverse and could be a valuable resource for trait association mapping, crop breeding and germplasm management.     

基于SSR的四川花生遗传多样性分析

[目的]研究旨在了解四川花生资源的遗传多样性及表型性状与分子标记的关联分析,为花生分子育种及资源库构建提供理论依据。[方法]鉴定分析57份不同来源花生资源材料的4个农艺性状及4个品质性状,并利用SSR标记研究57份花生材料的遗传多样性,对SSR标记与表型性状进行聚类及关联分析。[结果]表型性状鉴定结果显示花生资源的8个性状中,6个变异较大、多样性较好。67对SSR引物中,有效引物39对,获得多态性条带53条,平均每个引物扩增1.36条,平均Nei"s 基因多样性0.2288、平均Shannon"s 指数0.3695,最远遗传距离为0.51。SSR分子标记聚类分析将57份资源聚为2大类群,GLM分析发现多个与蛋白质含量、株高、含糖量的关联标记。[结论]研究结果表明,四川不同区域间花生遗传多样性较丰富,品种类型单一,聚类及关联分析结果可为四川花生突破性新品种选育的亲本选择提供提供重要参考。     

DNA profiling and genetic diversity of Korean soybean (<Emphasis Type="Italic">Glycine max</Emphasis> (L.) Merrill) landraces by SSR markers

Approximately 7,000 accessions of Korean soybean (Glycine max (L.) Merrill) landraces, largely composed of three collections, the Korea Atomic Energy Research Institute’s soybean (KAS), the Korean Crop Experiment Station’s soybean (KLS) and the Korean Agricultural Development and Technology Center’s soybean (KADTC) collections, have been conserved at the Rural Development Administration (RDA) genebank in Korea. The accessions within collections were classified based on their traditional uses such as sauce soybean (SA), sprouted soybean (SP), soybean for cooking with rice (SCR), and OTHERS. A total of 2,758 accessions of Korean soybean landraces were used to profile and to evaluate genetic structure using six SSR loci. A total of 110 alleles were revealed by at the six SSR loci. The number of alleles per SSR locus ranged from 9 to 39 in Satt187 and Satt_074, respectively. The number of alleles ranged from 87 in the KADTC collection to 96 in the KLS collection, and from 63 in the SCR group to 95 in the SP group. Nei’s average genetic diversity ranged from 0.68 to 0.70 across three collections, and 0.64 to 0.69 across the usage groups. The average between-group differentiation (G _st) was 0.9 among collections, and 4.1 among the usage groups. The similar average diversity among three collections implies that the genetic background of the three collections was quite similar or that there were a large number of duplicate accessions in three collections. The selection from the four groups classified based upon usage may be a useful way to select accessions for developing a Korean soybean landrace core collection at the RDA genebank. DNA profile information of accessions will provide indications of redundancies or omissions and aid in managing the soybean collection held at the RDA genebank. The information on diversity analysis could help to enlarge the genetic diversity of materials in breeding programs and could be used to develop a core collection.     

国外栽培豌豆遗传多样性分析及核心种质构建

从111对备选SSR引物中筛选出能扩增出清晰稳定单一带的多态性引物21对及其最佳退火温度, 并优化了豌豆SSR标记实验体系。利用上述引物, 对来自于67个国家的731份豌豆栽培种质(Pisum sativum L.)进行遗传多样性分析与核心种质构建。共扩增出109条多态性带, 每对引物平均扩增出5.19个等位变异。SSR等位变异在各大洲间分布不均匀, 有效等位变异数、Shannon’s信息指数(I)洲际间差异明显。各大洲资源群间遗传多样性差异显著, 其中亚洲最高(I = 1.1753), 欧洲其次(I = 1.1387), 俄罗斯联邦(I = 1.0285)、美洲(I = 1.0196)、非洲(I = 0.9254)、大洋洲(I = 0.8608)依次降低。利用Popgene 1.32软件, 依豌豆栽培资源洲际间Nei78遗传距离可聚类成2个组群和4个亚组群; 基于Structure 2.2软件分析, 国外栽培豌豆资源实际由3大类群组成, 并与Popgene 1.32聚类结果呼应得较好。上述两种分析方法均表明, 国外栽培豌豆类群的遗传多样性与其地理分布相关。设计并实践了一套基于Structure分析的科学可靠、逻辑性强的核心种质构建标准化方案, 并依此构建了一套以6.57%的资源(48份)涵盖总体84.4%等位变异的国外栽培豌豆核心种质。     

Microsatellite (SSR) variation in a collection of Malus (apple) species and hybrids

A collection of 142 accessions of 23 Malus species, derived hybrids and cultivar accessions from the USDA-ARS Plant Genetic Resources Unit's core collection, which represents an extensive range of Malus species, was screened with a set of previously described SSR (simple sequence repeat) markers. The markers were used to determine genetic identities, estimate genetic diversity, identify genetic relationships among the accessions, and determine the utility of SSR primers developed from Malus ×domestica for making genetic assessments across the whole Malus genus. All eight primer pairs amplified multiple fragments when used in polymerase chain reactions with DNA from these accessions. High levels of variation were detected with a mean of 26.4 alleles per locus and a mean direct count heterozygosity across all eight loci equal to 0.623. The eight primer pairs used in this study unambiguously differentiated all but five pairs of accessions in this collection of 142 accessions of 23 Malus species, derived hybrids and cultivars. These SSR data were not useful in identifying genetic relationships among this diverse collection of accessions, with the majority of the accessions not clustering in ways concordant with taxonomic information and/or geographic origin. The resulting phenogram resolved only two meaningful clusters, for the taxonomically isolated Section Chloromeles and for M. fusca accessions, reflecting genetic relationships arising from geographic origin. The detection of identical accessions in the collection, which were previously considered to be unique, highlights the critical need to further bolster collections of certain Malus species. This revised version was published online in July 2006 with corrections to the Cover Date.     

花生栽培种(Arachis hypogaea)类型间遗传差异的SSR分析

本文采用110对SSR引物分析28份花生栽培种资源(7份多粒型、5份龙生型、8份普通型和8份珍珠豆型)间的遗传差异,其中有46对引物在不同品种间检测出2～9个等位基因,多态性信息量(PIC)为0.080～0.869.对28份材料的聚类分析表明,SSR聚类结果与根据形态特征的分类结果基本一致,但在多粒型品种上存在一定差异.标记pPGSseq15C12在本研究中所有的珍珠豆型品种上均扩增出特异性条带,序列分析表明该标记在珍珠豆型与其它类型间扩增片段的差异是由于ATT重复次数不同所致.     

利用SSR标记分析橡胶草种质资源的遗传多样性

为了解橡胶草种质的遗传背景和遗传多样性,为今后橡胶草育种提供理论依据。利用23对SSR引物对96份橡胶草材料进行遗传多样性分析。结果显示,23对SSR引物通过扩增得到71个等位变异,等位变异范围2-6个,平均等位基因数为3.09个。通过聚类分析,俄罗斯材料和美国材料与新疆7个居群材料被分为2大类群,类群I包含所有俄罗斯和美国材料以及5份新疆野生材料,类群II包含其余新疆7个居群的材料;俄罗斯和美国材料同属于亚群A,平均遗传相似度为0.88,说明它们存在紧密的亲缘关系;新疆7个居群的材料被分为5个亚群,显示丰富的遗传多样性,而且相互之间存在复杂的遗传关系。本研究结果证明了SSR标记能够有效地用于橡胶草的遗传多样性研究,为以后的橡胶草种质收集和遗传育种提供重要依据。