17份苎麻栽培品种的RAPD分析

苎麻属于荨麻科是起源于我国的一种纤维与饲料作物，主要分布于热带、亚热带，少数达温带。我国的苎麻种质资源十分丰富，在苎麻品种资源的形态特征、农艺性状等方面已有较多的研究，建立了基于形态特征的分类系统。由于苎麻是以无性繁殖为主的宿根型作物，在遗传上高度杂合，自交难以获得纯系，加之其染色体小，从细胞遗传学的水平进行遗传背景的研究较为困难，因而人们对苎麻品种的了解大多局限于形态特征与农艺性状，在育种亲本的选配上具有较大的盲目性。通过对RAPD指纹图谱的统计分析，可以对其遗传背景与亲本选配提供DNA分子水平的依据。本研究选用在地理来源、形态特征和农艺性状上有一定差异的17份苎麻品种，利用RAPD分子标记构建其基因组指纹图谱，为苎麻种质资源研究和遗传育种提供更多的依据。     

姜品种遗传多样性的RAPD分析

利用RAPD技术对20个姜(Zingiberofficinale)品种进行了遗传多样性的研究。从200多个引物中筛选出25个有效引物,共扩增出171条DNA带,其大小分布在100￣3500bp之间,其中111条为多态性,约占总数的64.91%,平均每个引物的扩增带为6.8条。利用25个有效引物扩增的DNA带数计算出品种间的J系数,并进行UPGMA聚类分析,在此基础上,建立了中国姜品种亲缘关系系统树。在相似性系数0.67处,20个品种分为Ⅰ、Ⅱ、Ⅲ和Ⅳ类。Ⅰ类可分为A、B和C组;Ⅳ类可分为D和E组。其中,A组可再分为A1和A2亚组;B组可再分B1和B2亚组。各亚组内相似性系数较大,表明它们之间的亲缘关系较近,但也存在着一定的差异。     

白骨壤种群遗传变异及分化的生态分析研究

白骨壤（Auicennia marina)为红树植物。采用垂直板型聚丙烯酰胺凝胶电泳测定了5个白骨壤种群遗传多样性、遗传分化，分析了白骨壤种群的样地气候和土壤理化指标。研究结果表明，环境因子与白骨壤种群的Aat-1A，Aat-1D,Me-1B,Me-1C4个等位基因相关性显著，说明环境因子对这4个等位基因具有选择压力，他们的变化与环境变量有关。     

大豆空间诱变突变体的RAPD分析

本研究应用RAPD技术在分子水平进行大豆空间诱变突变体的差异性分析,为大豆空间诱变育种提供理论基础。首次应用RAPD标记对大豆空间诱变的12个品系及4个原始对照种进行多态性分析。随机选用的70个RAPD引物对原始对照种及12个空间诱变品系进行扩增,共获得247条DNA谱带,其中多态性谱带39条,总多态性位点比率为15.8%,品系间多态性位比率在1.43%~10%之间,扩增片段长度在250-2100bp之间。因此,通过空间诱变能够在DNA水平上导致大豆遗传物质变异,并且RAPD是一种研究植物空间诱变材料的较有效的分子生物学方法。     

华东竹黄菌不同居群遗传分化的RAPD分析

为了解竹黄地理居群间的遗传分化,本研究采用随机引物扩增多态性DNA分子标记技术对江苏、安徽和浙江3省的8个居群共32个竹黄样本进行了遗传多样性分析。从50个RAPD引物中筛选得到了5个随机引物,对供试材料的DNA进行扩增,共检测出77个位点,其中多态性位点52个,多态性位点比率为67.53%。UPGMA聚类分析结果表明,这8个居群分为三类：安吉居群、临安居群、宜兴居群、广德居群和泾县居群聚为一类;宁国居群和休宁居群聚为一类;淳安居群单独为一类。遗传多样性分析表明8个竹黄居群中,淳安居群的遗传多样性水平最高,安吉居群的遗传多样性水平最低。Nei＇s基因多样性指数和Shannon信息指数均表明竹黄物种水平的遗传多样性高于居群水平。     

桑树有性杂交后代与双亲基因组DNA的RAPD分析初报

用６个随机引物对桑５个杂交亲本和５个杂交后代基因组ＤＮＡ进行ＲＡＰＤ分析，它们均表现出丰富的ＤＮＡ多态性，反映了桑树遗传背景多种性和品种间的差异性。杂交后代与双亲间的基因组ＲＡＰＤ图谱比较，不同杂交组合和不同引物间有较大差异，５个Ｆ１代的ＤＮＡ片段绝大多数与双亲或单亲相同，但杂交后工中也出现了少数特异性片段。     

快中子辐照紫花苜蓿的生物学效应与RAPD分析

采用直线加速器产生3.60×1011、7.10×1011和3.54×1012/cm2 3种辐照注量的快中子处理肇东苜蓿干种子,对其进行种子发芽试验、幼苗生长和RAPD分子标记分析。研究表明,经3种注量快中子处理后,肇东苜蓿种子发芽势和发芽率显著高于对照;幼苗的苗高和根长小于对照,随着快中子处理注量的增加,幼苗苗高降低和...     

22个甘薯品种（系）遗传背景的RAPD图谱分析

通过１０个随机引物的ＤＮＡ扩增，首次报道了２２个甘薯品种的ＲＡＰＤ多态性，不同品种具有不同的ＤＮＡ扩增带型，反映了不同品种遗传背景上的差异，计算了２２个甘薯品种的Ｎｅｉ‘ｓ相似系数与遗传距离，建立了它们的ＵＰＧＭＡ系统树，并通过聚类分析与对应分析，讨论了２２个甘薯品种间的亲缘关系，ＲＡＰＤ多态性分析从分子水平上反映了甘薯品种复杂的遗传背景，并为育种的亲本选配提供了依据。     

RAPD analysis of genetic relationships of seven flax species in the genus Linum L

The wild progenitor of the cultivated flax (Linumusitatissimum L.) has been long hypothesized to beL. angustifolium Huds., largely fromseveral phytogeographic cytogenetic and phenotypic studies, but no molecularstudies on the issue are found. In this study, we genotyped 12 flax accessionsrepresenting seven flax species in the genus Linum with 527RAPD loci from 29 informative RAPD primers and analyzed their geneticrelationships with simple matching, Dice's and Jaccard's similaritycoefficients. Large RAPD variations were found among the flax species.L. usitatissimum andL. angustifolium had a higher RAPDsimilarity than the other pairs of flax species and these two species wereconsistently clustered in the same group with all of the similarity coefficientsused. This molecular finding provides an additional support for the hypothesisof L. angustifolium as the wildprogenitor of cultivated flax.     

Characterization of genetic variation and relationships among Choix germplasm accessions using RAPD markers

Choix, a plant in the tribe Maydeae of the grass family, has been cultivated in Asia for several thousand years. It is a potential gene resource for improvement of other cereal crops because of its nutritional value and tolerance to stress. Genetic variation and relationships among 21 Choix lachryma-jobi L. accessions were characterized by random amplified polymorphic DNA (RAPD) markers. A total of 205 DNA fragments across all materials were amplified with 31 random primers, averaging 6.61 per primer. Among amplified fragments, 115 showed polymorphism averaging 3.71 per primer. Of amplified markers, 56.1% were polymorphic, indicating considerable variation at the DNA level among these accessions. Some fragments were accession-specific. Pair-wise genetic similarity (GS) among 21 accessions ranged from 0.809 to 0.301. The 21 accessions clustered into two major groups. Three exotic Choix accessions clustered together. Three other Choix accessions, collected from Guangxi, China, clustered into a cohesive subgroup. Four wild types of Choix clustered into the same subgroup. These results indicated that the classification by RAPD data reflected the differences in geographic origins and evolution in Choix.     

Intraspecific and interspecific variation in Setaria revealed by RAPD analysis

Random amplified polymorphic DNA (RAPD) analysis was applied to foxtail millet (Setaria italica) and other Setaria species in order to assess the degree of polymorphism among and within the species and to investigate their genetic relationships. Twenty accessions of foxtail millet, five of green foxtail (S. viridis), five of yellow foxtail (S. glauca), one each of S. germanica, S. verticilliformis, S. pallidifusca, S. macrostachya, S. sphacelata and S. faberi, and one unidentified, were evaluated for variability using a set of 19 random 10-mer primers. A total of 148 markers were scored for all the accessions. Wide variations in banding profiles among species were observed with nearly every primer used. The results showed that foxtail millet and S. glauca had a considerable degree of variation. The geographic differentiation of RAPD patterns in foxtail millet accessions examined seemed to exist. The present study confirmed that foxtail millet is more closely related to green foxtail than to other species in Setaria, providing support for the origin of foxtail millet from S. viridis and the conspecificity of these two species. The results confirmed that S. germanica and S. italica are conspecific and the former can be replaced by the latter. Setaria glauca and S. sphacelata are distinct from foxtail millet, implying that elite traits found in these two species are relatively difficult to be used in foxtail millet improvement. This study demonstrates that RAPD analysis can be used in assessing intraspecific and interspecific variation in foxtail millet and its wild relatives.     

Genetic variation analysis in the genus Lathyrus using RAPD markers

RAPD analysis was applied to five species belonging to the genusLathyrus (Fabaceae): L.sativus, L.cicera, L.ochrus, L.sylvestris and L.latifolius. All the species under study belong to thesection Lathyrus except L.ochrus which is in section Clymenum.Nine populations representing these species were used and ten random10-mer primers were sampled. A total of 129 amplification products,ranging in size from 0.3 to 3 Kb, were generated. Partitioning ofvariation was studied using the AMOVA technique. The genetic variation proved tobe nearly equally distributed among species and among populations withinspecies. A similar approach was carried out to distinguish populations, whichproved to be efficient. The between population dissimilarities were calculatedand a dendrogram of genetic relationships was drawn. The RAPDs obtained weresufficient to distinguish between the two accessions of a species and toseparate these accessions by clustering them according to species. A highgenetic similarity between the populations of L.sylvestris and L.latifolius was established. A similar result is also shownfor the populations of L. sativus andL. cicera.     

RAPD markers in the analysis of genetic diversity among common bean germplasm from Central Himalaya

A set of 99 common bean germplasm collected from central Himalaya was investigated for their genetic variability using random amplified polymorphic DNA (RAPD) markers. Ten oligonucleotide primers, selected from 60 initially screened, generated 123 amplicon products. Of these, two amplicons were shared by all the accessions whereas 112 were polymorphic at least in two pair wise comparison. Nine unique bands identified were as low as 0.32 kb M.W. to as high as 3.5 kb and were confined to eight collections. All primers produced polymorphic amplicons though the extent of polymorphism varied with each primer. The primer OPF-17 was found to be most powerful and efficient as it generated a total of 17 bands of which 15 were polymorphic. RAPD markers data were analysed statistically using NTSYSpc.2.02e software and a dendrogram was generated using Jaccard’s similarity coefficient. The similarity coefficient values varied from 0.19 to 0.91. Grouping analysis revealed the categorization of 99 germplasm into 12 major branches with different level of similarity. Three branches namely branch 2, 3 and 5 out of 12 had only one accession. Branch 1 which consisted of three accessions was the most divergent as revealed by Jaccard’s similarity coefficient. Branching pattern of the accessions did not show any correlation with morphological data or altitudinal alignment of the accessions.     

Population genetic structure of Milicia speciescharacterised by using RAPD and nucleotide sequencing L.

Milicia species(M. excelsa andM. regia, Moraceae, theirokos) are among the most useful indigenous rain forest treespecies in Africa. They are not grown in plantations but extractedfrom the natural forest at an unsustainable rate. The majorconstraint on cultivation and afforestation is thegall-forming insect Phytolyma lata, whichdestroys seedlings through gall formation, causing dieback of theshoot. Genetic diversity studies should aid the design ofconservation and resistance-breeding strategies. This study,therefore, aimed to investigate the genetic variability inMilicia from three West African countries andthe power of bulk-family DNA in partitioning of geneticdiversity. Genetic variation within and between 5 natural populationsof Milicia from Ghana, Côte d'Ivoireand Sierra Leone was investigated using random amplified polymorphicDNA (RAPD) and non-coding chloroplast DNAsequencing. RAPD analysis of 41 DNA samples with 8 primers produced atotal of 74 bands with 40 bands (54.1%) beingpolymorphic. Dendrogram analysis produced 2 major clusters separatingdry and moist/wet ecotypes. Sub-clustering furtherseparated accessions by forest type and/or geographic region. Agreater proportion of the total genetic variability was attributed tovariation between populations (62.2%) than withinpopulations (37.8%). Sequencing of chloroplasttRNA^Leu intron (cptrnL) and intergenic spacer(cpIGS) between cptrnL and tRNA^Phe(trnF) did not show any variation. The RAPD analysissuggests that trees from wet/moist sites are mostlyM. regia, while those fromdry sites are mostly M.excelsa. Sequencing results, however, suggestthat the two species are closely related. These results are discussedwith reference to conservation strategies.     

Low levels of genetic diversity detected by RAPD analysis in geographically distinct accessions of Bacopa monnieri

Brahmi (Bacopa monnieri) is atraditional Indian medicinal plant known for its natural nootropicaction of saponins present in large amount in its shoots. Acollection of 24 B.monnieri accessions from differentagro-climatic zones of India and an introduction from Malaysiamaintained in the field genebank at CIMAP was analysed for RAPDvariation. Among the 40 random primers tested, 29 primers generatedone or more polymorphic bands. The number of polymorphic bandsgenerated was primer dependent, ranging from 2 to maximum of 8.Similarity matrices were generated from the RAPD data on the basis ofNei's estimates of similarity indices and dendrograms wereconstructed based on UPGMA clustering. All the accessions were foundto be in the range of 0.8–1.0 of similarity, which isindicative of a narrow genetic base among the various accessions witha medium level of polymorphism. It was possible to differentiateindividual accessions, showing differences in morphological andgrowth properties at DNA level. The observed low levels of geneticvariation were attributed to interplay of sexual and vegetative modesof reproduction and similarity of local environments in habitats ofB. monnieri.     

Genetic variation in captive population of chinese alligator, Alligator sinensis, revealed by random amplified polymorphic DNA (RAPD)

Chinese alligator (Alligator sinensis) is an endemic species in China. The likely extinction of it in the wild has been recognised. To prevent this species becoming extinct, the Anhui Research Centre of Chinese Alligator Reproduction (ARCCAR) was established in Xuanzhou, Anhui Province in 1979, where has been established the largest captive population of Chinese alligator (XZSP) in the world. Another farm (CXSP) was established by villagers in Changxin, Zhejiang Province. The results of an investigation of the two captive subpopulation structures by genetic analysis are presented in this paper. We examined the genetic variation in the two captive subpopulations using RAPDs. Thirty-one random primers were selected among 199 random primers screened. A total of 193 reproducible RAPD fragments were scored among 43 individuals, of which 21 (10.88%) were polymorphic. The genetic distances between 43 individuals ranged from 0 to 0.0376 with average of 0.0104±0.0055 S.E. The genetic similarity in CXSP (0.9948±0.0029 S.E.) was higher than that in XZSP (0.9894±0.0055 S.E.). The founder effect is a possible explanation for very low genetic variation in CXSP. Analysis of the RAPD data showed that the mean phenotypic band frequencies of each polymorphic loci was 0.6656±0.3730 S.E. The lowest phenotypic band frequency (0.0233) was found in four of those polymorphic loci. There was no genetic difference between the two subpopulations (D_ij=0.0009). According to the dendrogram and the distribution of polymorphic fragments in two subpopulations, CXSP originated genetically from XZSP. This paper summarises a preliminary research on genetic structure in populations of Chinese alligator. Although there is higher genetic similary (0.9896±0.0055 S.E.) in captive population of A. sinensis, we did not determine whether or not loss of genetic variation had occurred in relation to a wild control population. The data of malformed offspring will be collected carefully, and wild samples be added to set up a control population in future study.     

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     

Population genetic structure in Lens taxa revealed by isozyme and RAPD analysis

An understanding of the genetic structure of populations is vital for the formation of optimum collection, conservation and utilization strategies for plant genetic resources. This is of particular importance in the case of in-situ conservation, a strategy gaining in popularity. The population genetic structures of five wild lentil taxa, Lens culinaris subsp. orientalis, L. odemensis, L. ervoides, L. nigricans and L. lamottei were investigated using isozyme electrophoresis and random amplified polymorphic DNA (RAPD). Approximately 20 plants from each of 5 populations per taxon were screened for variation at 11 isozyme loci and using three RAPD primers. Levels of variation were generally low, although considerable variation existed in the levels of diversity found within populations of L. culinaris subsp. orientalis and L. lamottei. Comparison of the results obtained in this study with the results obtained in a previous study indicate that this is a trend occurring across all species. It implies that levels of diversity within populations must be measured and considered prior to targeting of specific populations for in-situ conservation. Analysis of molecular variance of both isozyme and RAPD data revealed that between 78% and 99% of the variation was attributable to between-population differences. Isozyme results from L. lamottei populations were, however, contradictory. Possible explanations for this difference are discussed.