中国江、浙地区栽培大麦遗传资源的RAPD研究

采用随机扩增多态性（RAPD）标记，探讨了我国部分栽培大麦品种的遗传背景。结果表明：200个随机引物中，有30个引物扩增出的产物具有多态性，30个引物共扩增出223条谱带，其中130条谱带具有多态性，每个引物可扩增出2~9条多态性谱带，平均4.19条。67个大麦品种平均表型多样性值0.369，裸麦的表型多样性高于皮麦的表型多样性     

菊花芽变和相似品种的RAPD分析

本实验在形态学分析的基础上,采用5对中国传统菊花的芽变品种和2组形态相似品种,运用随机扩增DNA多态性（random amplified polymorphic DNA,RAPD）分子标记方法对其进行了品种鉴定。通过反复试验,建立了稳定的RAPD反应体系;从22个20碱基随机引物中筛选出4个高效引物,扩增出13条带,扩增的多态性片段多在501～1000bp之间,其中有2个引物（ch1．21和ch1．25）能将试验中的7组材料全部清楚地区分开。研究结果表明：4个高效引物的RAPD分析能够有效地将选定的样本区分开。因此作者提出RAPD分析方法可以应用到菊花芽变及相似品种鉴定中。这就为进一步开发更多RAPD随机引物,开展菊花的品种鉴定和保护工作提供了参考资料。     

水稻抗病毒基因同源序列多态性与品种鉴定

利用已知植物抗病基因不同保守序列设计的S1／AS3和XLRRfor/XLRR rev两对引物对22个水稻品种DNA进行PCR扩增和聚丙烯酰胺凝胶电泳。分析结果表明：水稻抗病基因同源序列类型丰富，2对引物共扩增出143条带，品种间有差异的谱带92条，根据谱带差异可将供试品种完全鉴别出来，证明抗病基因同源序列分析可以用于水稻品种鉴定。     

山西冬小麦品种Waxy蛋白分析及分子标记研究

利用聚丙烯酰胺凝胶电泳(SDS-PAGE)法分析了山西100份小麦品种(系)Waxy蛋白的缺失类型,筛选出缺失Wx-B1蛋白亚基的材料8份。利用2个STS标记和1个SSR标记对不同Waxy蛋白缺失类型进行鉴定,验证其在分子标记辅助育种中的有效性,结果表明:Wx-7A位点的STS引物在野生型中扩增出1条450 bp的特异带,而在缺失Wx-A1蛋白亚基的突变材料中扩增出1条327 bp的特异带;Wx-4A位点的STS引物在野生型中扩增出1条440 bp的特异带,缺失Wx-B1蛋白亚基的突变材料中没有该扩增片段;Wx-7A,Wx-7D位点的SSR引物在野生型中分别扩增出1条265 bp和1条204 bp的特异带,在缺失Wx-A1和Wx-D1蛋白亚基的突变材料中没有扩增出该特异带。这3个标记可以用于分子标记辅助育种。     

杂交稻部分不育系与恢复系的SSR分类

选用分布于水稻(Oryza sativa L.)12条染色体上的36对SSR(simple sequence repeats)引物，分析了5个光温敏核不育系、7个细胞质雄性不育系及54份来自不同生态类型恢复系或品种的遗传差异。在供试材料中共检测出300条多态性片段，平均每对SSR引物检测到8.33条。分析结果表明，(1) SSR标记明确地把供试的66份水稻材料中的65份区分开来，和已知系谱的亲缘关系多数吻合，与表型性状聚类结果也有一定的相似性。(2) 以GD=0.73为标准，可准确地将籼稻、粳稻、野生稻三大类区分开；以GD=0.63为标准，又可区分出籼稻大类中带有粳稻或野生稻血缘的品种。表明SSR标记对籼稻、粳稻、野生稻品种的分类灵敏度高、结果可靠；并筛选出可用于鉴别水稻籼粳类型的10对特异性引物。(3) 以GD=0.56为标准，将供试材料划分在8个生态类型中，为生产上杂优组合亲本的选配提供了一些有益的参考。同时，生产上常用的一些杂交稻亲本划分在不同的生态类型中，表明强优势组合亲本间的遗传差异一般较大。     

烟草品种RAPD分子标记多态性与品种鉴定

用235个引物对来源于中国，美国等国的23个烤烟和地方晒晾烟品种基因组进行了RAPD分子标记分析。结果表明：235个不同的随机引物中有25个（占10．64％）可以扩增出至少在两个品种间表现多态性的产物，利用其中16个引物扩增出128条带，其中46条品种间具有多态性。建议将RAPD技术应用于烟草品种鉴定。     

基于SSR分子标记的41份茶树种质资源遗传多样性及亲缘关系分析

为了对豫南茶树种质资源进行初步鉴定和评价，以豫南茶树种质资源圃内41份无性系品种为材料，利用SSR分子标记技术进行遗传多样性及亲缘关系分析。结果表明：从33对引物中筛选出26对扩增较好的引物，26对引物共扩增出102条谱带，平均每对引物扩增条带4条，最少为2条，最多为7条，检测的平均观测等位基因数2个，平均有效等位基因数1.8664个，平均Nei’s遗传多样性0.4626，平均Shannon信息指数0.6550，引物多态信息量最大值0.80，最小值0.23，平均值0.62。聚类分析结果显示，在相似系数为0.5处，将41份材料分为4大类群，地理来源和遗传背景相近的大都聚在一起，供试品种的遗传距离为0.08～1.87，说明资源圃内品种间遗传基础较宽。     

苎麻栽培品种亲缘关系的RAPD分析

从1000多份苎麻种质资源中筛选出抗旱性较强和较弱的栽培品种各6个,选用25个随机引物,对其总DNA进行随机扩增.有1 2个引物扩增得到了稳定的RAPD图谱;扩增出的片段分子量在0.6～5.15kb之间,条带数在3～15条之间,共扩增出90个条带;采用聚类法中的中间距离法,对12个品种的相似系数聚类生成树状图谱,分为两类三组,揭示了供试品种     

惠州引种马铃薯品种的ISSR分子鉴定

采用ISSR分子标记技术对7个惠州市引种的马铃薯品种进行遗传多样性研究.从30条ISSR引物中共筛选出3条引物,对7个马铃薯品种基因组DNA进行有效扩增,共扩增出25条带,其中多态性带20条,多态性比率为80%.用NTSYS-pc22.10 e软件计算各马铃薯品种阃的Jaccard遗传相似系数,7个马铃薯品种之间的遗传相似性系数界于0.35～0.85,平均遗传相似性系数为0.693.利用UPGMA进行的系统聚类分析表明,7个马铃薯可划分成2组,广引1号独立聚为一类,剩下6个马铃薯聚为另一大类.试验结果说明,引种的马铃薯品种间亲缘关系较近,遗传基础狭窄,有必要进一步扩大引种的数量和范围.     

辣椒抗黄瓜花叶病毒(CMV)基因的ISSR标记

辣椒(Copicum annuum L.)抗黄瓜花叶病毒(CMV)一直是辣椒育种的主攻目标之一.本研究以辣椒抗CMV品种VC16a和感CMV品种SS69杂交的F2群体60个单株材料,通过人工接种鉴定,采用高抗单株和高感单株分别构建抗、感基因池,利用BSA法筛选了40条ISSR引物,其中引物I-34在抗感病池中扩增出450 bp多态性片段,通过F2单株验证后证明I-34450与抗CMV基因紧密连锁,其遗传距离为27.3 cM,为辣椒抗CMV分子标记辅助育种奠定了基础.     

四川省丁香假单胞猕猴桃致病变种的遗传多样性分析

为明确四川省猕猴桃溃疡病菌丁香假单胞菌猕猴桃致病变种(Pseudomonas syringae pv.actinidiae,Psa)的遗传多样性及群组划分与地理来源的相关性。以四川省不同地理来源的40个Psa菌株为研究试材,用rep-PCR技术进行分子标记,NTSYS软件分析UPGMA聚类。3对rep-PCR检测引物(REP、ERIC和BOX)共获得42个位点,其中38个为多态位点,占90.5%。UPGMA聚类结果显示,以相似系数为0.70阀值时,40个Psa菌株被分为2个类群(Ⅰ、Ⅱ),其中85.0%的菌株属于第Ⅱ类群;在相似性系数为0.80时,第Ⅰ类又可分为2个亚类(Ⅰ-1、Ⅰ-2),第Ⅱ类则分为5个亚类(Ⅱ-1、Ⅱ-2、Ⅱ-3、Ⅱ-4、Ⅱ-5),菌株无明显的采集地聚类。以上结果表明,四川省各地区的猕猴桃溃疡病菌菌株具有较高的遗传多样性,但其遗传变异与菌株地理来源无明显相关性。     

Genetic variability measures among Bromus catharticus Vahl. populations and cultivars with RAPD and AFLP markers

The objectives of this study were to optimize RAPD and AFLP techniques in B. catharticus, and to determine the genetic variability of populations and commercial prairie grass cultivars with the aforementioned molecular markers. Two populations with contrasting morphological characteristics were evaluated from individual and bulked DNA samples using RAPD markers. Both analyses showed a similar information about inter population variability. Each accession was sampled by a single leaf bulk of 10 plants. Accession similarities were established with 276 RAPD and 714 AFLP bands using Jaccard similarity coefficient. The dendrogram of the accessions using RAPD markers showed that they shared high similarity values (>94%). A similar result was obtained with AFLP markers (similarity values >98%), revealing a narrow genetic basis in the analyzed accessions. Consequently, molecular characterization of germplasm should be considered in addition to morphological criteria, to choose the parental genotypes for breeding programs of this forage crop. The AFLP technique was more efficient to detect DNA polymorphism in our experiments and unique fingerprints were detected for all the accessions. RAPD is a simple and non expensive technique, suitable to estimate genetic similarity. This revised version was published online in August 2006 with corrections to the Cover Date.     

A genomic search for the gene conferring resistance to fusarium wilt in tomato

Fusarium wilt is an economically important disease of tomatoes, caused by the soil-born fungus Fusarium oxysporum f. sp. lycopersici. There are three host-specific races of this pathogen. The dominant tomato gene I-2 confers resistance to race 2. The I-2 fusarium resistance gene was mapped genetically to chromosome 11 of tomato, between the RFLP markers TG105 and TG36, 0.4 centiMorgan (cM) from TG105. A mean value of 43 kb for each cM was assigned in the vicinity of I-2. We have generated new RFLP markers in the region by chromosome walking from TG105 towards I-2 on lambda clones, and by subcloning a 350 kb long YAC clone (YAC 8) that contains TG105. These RFLP markers were mapped physically on YAC 8 by PFGE. The location of I-2 relative to these markers was genetically estimated using a recombinant inbred (RI) segregating population. The order of the markers according to the RI population is inconsistent with their order on the physical map. A cDNA clone, D14, that was isolated by YAC 8, turned out to be 53% similar to xanthine dehydrogenase from mammals and flies. Antibodies raised against a part of the protein encoded by D14 recognize cross reacting material of MW 80 kD, that is highly enriched in nodules of legumes, and seems to be induced by various environmental and pathogenic stress conditions.     

同一病株西瓜枯萎病菌RAMS分析

利用RAMS(Randomamplifiedmicrosatellites)分子标记技术对河北省不同地区的3个西瓜枯萎病病株分离物Fon1、Fon2、Fon3各10个单孢菌株进行了基因组多态性分析。10个RAMS引物进行扩增,Fon1共扩增出39条带,其中多态性条带9条;Fon2共扩增出40条带,多态性条带5条;Fon3共扩增出40条带,多态性条带4条。结果分析表明,同一病株分离物的不同单孢菌株之间在分子水平上存在遗传差异性。     

XL-90等美洲黑杨杂交子代ISSR分子鉴别

为了探讨ISSR分子标记在美洲黑杨杂交子代分子鉴别和分子标记辅助育种中的应用,笔者以15个黑杨无性系为研究对象,进行ISSR分子标记研究。①经单因素对比实验,建立适合黑杨无性系的ISSR-PCR分子反应体系,即在25 μL反应体系中加入引物1.0 μmol/L,模板30 ng,Taq酶1.5 U,dNTP 0.25 mmol/L,Mg2+2.0 mmol/L。反应程序为94℃加热3 min,使模板DNA变性,然后进入下列温度循环：94℃变性45 s、56℃退火30 s、72℃延伸1 min,共计35个循环。循环结束后在72℃延伸5 min,以保证DNA延伸彻底。②筛选出10个ISSR引物对15个黑杨无性系进行ISSR分析。共检测到63个位点,各无性系的多态位点百分率在20.63%~30.16%之间。多态位点百分率最高的为XL-77、XL-83、XL-101、2KEN8和I-69;多态位点百分率最低的为XL-92、XL-90。③通过各无性系的Nei遗传距离与UPGMA聚类分析,除欧美杨A65/31外,其他所有美洲黑杨无性系聚为1个类群3个亚群,美洲黑杨杂交子代间遗传分化及亲缘关系通过ISSR-PCR特异性标记谱带可以得到准确鉴别。     

Breeding systems in Coix lacryma-jobi populations

Summary Six populations of Coix lacryma-jobi with distinct characters were studied to evaluate the presence of autonomous apomixis and pseudogamy, and to determine its implications and effects in the calculations of the rate of breeding. For this reason, two types of genetic markers were used-morphological markers and isozymatic markers.The results show that autonomous apomixis does not seem to occur in these populations. Further experiments are necessary to prove the presence of pseudogamy in one of the populations. The rate of natural outcrossing in the grain types Rosario, Rosadlay and I-47 fluctuated around 35.9% using estimates based on isozymatic markers. The rate of natural outcrossing was 37.4% in the Adlay population using morphological markers. A population composed of tall individuals, named Tailândia, which has a greater vegetative mass and fewer grains, presented a high level of natural outcrossing at 72.8%. This information is important for many reasons, such as: 1) guiding sampling strategies of genetic material, 2) in the organization and upkeep of germplasm banks, and 3) for plant breeding programs.     

利用RAPD分子标记分析玉米种质遗传多样性

以RAPD分子标记技术对玉米的10个品种的全基因组DNA进行PCR扩增,再用Popgene32软件和SPSS 13.0软件分析扩增结果,研究10个玉米的种质资源遗传关系。结果表明：（1）所选20个引物可扩增出214条RAPD条带;（2）所选引物扩增条带的多态性比率为86.4%,RAPD分子标记扩增10个玉米品种间的相似性系数分别在0.316-0.654之间;（3）用RAPD-PCR扩增条带的分析结果建立了遗传相关系数矩阵、构建了分子树状图、可将10个玉米品种分为3个类群;（4）RAPD分子标记适合于构建玉米的DNA指纹图谱,进行品种鉴定和遗传分析。     

Genetic organization of aromatic rice as revealed by RAPD markers: A case study in conserving crop genetic resources on farm

Summary On-farm conservation of landraces is one strategy to maintain the diversity of crop germplasm in local agro-ecosystems. The genetic structures of landraces are a key biological factor in on-farm conservation strategies. To accumulate a genetic understanding that will help establish a methodology for on-farm conservation, the genetic organization of landraces of aromatic rice in Namdinh province, Vietnam was analyzed using RAPD markers. Eighteen RAPD markers detected 38 genotypes among 320 aromatic rice samples growing at 23 sites of farmers' fields and in the experimental field that derived from 13 sites. Geographical variation was observed in the frequency of genotypes, whereas individual landraces could not be distinguished by RAPD markers. Genetic variation within a site was generally smaller than that among sites. The degree of genetic similarity of the plants in a site varied among sites, as did the number of genotypes. Changes in genetic structure over time were investigated using experimental populations each derived from approximately 30 plants from 13 farmers' fields. The differences detected by DNA markers between the genetic structural in the farmers' fields and those in experimental fields suggested that genetic drift is a major cause of these differences. The present study suggests that DNA markers are an essential means to monitor the genetic structures of heterogeneous landraces of rice, and are useful for selecting study sites for the on-farm conservation of genetic diversity as well as for successive monitoring.     

航天搭载小麦种子SP3代的遗传变异分析

为探讨航天搭载对小麦籽粒的诱变效应,给航天诱变育种提供理论支持,本研究利用酸性聚丙烯酰胺电泳和SRAP技术对航天搭载小麦品种白硬冬2号SP3 代种子的醇溶蛋白和基因组DNA进行了分析,结果表明航天诱变能够诱发醇溶蛋白和基因组DNA发生变异。在15个SP3代材料中,有8个材料的醇溶蛋白组成发生了变异,醇溶蛋白四个分区对航天诱变的敏感程度不同,以ω区最为敏感,产生的变异最多。利用25对SRAP引物对15个SP3代材料的基因组DNA变异进行了分析,共扩增出227条多态性条带,15个小麦航天诱变后代材料与对照间的遗传相似系数为0.821-0.937。     

Isolation and genetic characterization of a fertility-restoring revertant induced from cytoplasmic male sterile rice

Summary A male fertile revertant was isolated from M₁ of a cytoplasmic male sterile indica rice line II-32A, the dry seeds of which were treated with ⁶⁰Co- rays at a dose of 290 Gy. The acquired revertant T24 was morphologically and agronomically similar to II-32B, the maintainer of II-32A. Testcrosses of the revertant with II-32A and Zhenshan 97A showed that the revertant was able to restore the fertility of CMS lines. Genetic analysis of the progenies between T24 and II-32A, Zhenshan 97A XieqingzaoA and DZhenshan 97A, which have different cytoplasms, showed that the fertility restoration of four CMS lines by T24 involved one nuclear gene, indicating that T24 was a result of the mutation of one nuclear gene. The mechanism of the restoration of CMS line by T24 was obviously different from other restorers such as Minghui 63 and 20964, which were shown to behave in two gene mode in fertility restoration. The discovery of the revertant T24 contributes to the understanding of CMS and fertility restoration of CMS in rice. The T24 and its parent II-32A may constitute a pair of near isogenic lines for the restoring gene, which should be valuable materials for molecular genetic analysis of CMS.