中国北方引种的部分越橘品种的RAPD分析

利用RAPD技术对我国北方引种的15份越橘(Vaccinium spp.)栽培品种进行了遗传多样性分析。从70条随机引物中筛选出15条引物,共扩增出94个位点,其中多态性位点83个(88.3%)。材料间遗传相似系数变化为0.5426～0.8936,表明各品种间具有一定的遗传差异。UPGMA聚类分析结果可将供试材料分为2大类、5个亚类。聚类结果与各品种的杂交系谱相对应,从分子水平揭示了品种间的亲缘关系。     

黄瓜种质核心样本构建方法初探

 对来自不同国家或地区的90份代表性黄瓜种质进行了RAPD分析, 并利用其数据对构建黄瓜核心样本的方法进行了探讨。在聚类分析的基础上, 分别按初选核心样本的10%、15%、20%、25%、35%和45%抽取核心样本, 通过对它们的多态位点数、丢失位点数和遗传多样性指数的比较, 认为25%左右是构建黄瓜种质核心样本较为理想的比例; 另外经过对组内随机取样法、最大离差度法和最大遗传距离法3种不同抽样方法的比较, 认为最大遗传距离法较为适合用RAPD数据构建黄瓜核心样本。进一步的验证表明, 按上述方法构建的核心样本能比较好地代表初选核心样本, 同时也不能忽视保留样本的作用。     

DNA and morphological diversity of selected Greek tomato (Solanum lycopersicum L.) landraces

Utilizing inter-simple sequence repeats (ISSRs), the genetic diversity of 33 Greek tomato (Solanum lycopersicum L.) landraces and three cultivars, three cherry tomato (S. lycopersicum var.cerasiforme) cultivars and two accessions of Solanum pimpinellifolium L. was studied. Furthermore, 12 ISSR primers were also used to identify 27 morphotypes derived from 7 landraces. Based on Jaccard's coefficient, an average genetic similarity of 0.797 (ranged from 0.56 to 0.95) was found among the accessions. Cluster analysis using the UPGMA method placed all tomato landraces and cultivars into a single group, while the cherry hybrids and the S. pimpinellifolium accessions were placed in a second group. The ISSR data distinguished all the 27 morphotypes from each other and grouped the morphotypes derived from the same landrace together. The ISSR technology proved useful in describing genetic diversity among Greek tomato landraces and was capable of distinguishing the closely related morphotypes.     

Characterization of white sapote (Casimiroa edulis Llave & Lex.) germplasm using floral morphology,RAPD and AFLP markers

Floral morphology, random amplified polymorphic DNA (RAPD), and amplified fragment length polymorphism (AFLP) were used to characterize and verify genetic diversity within a white sapote cultivar collection and to develop molecular markers for germplasm identification. On the basis of floral morphology, the cultivars were classified into three types: type I included 23 cultivars with large ovaries and small anthers; type II included 13 cultivars with small ovaries and large anthers; and type III included one cultivar, named ‘Maltby’, with a large ovary and large anthers. DNA was isolated from 39 cultivars of white sapote and subjected to RAPD and AFLP analysis using 24 and 7 primers, respectively. One hundred and sixty-eight RAPD and 286 AFLP bands were used to assess genetic characterization among white sapote. Sixty percent of the RAPD and 77% of the AFLP amplification products were polymorphic among accessions. RAPD or AFLP markers differentiated all white sapote cultivars effectively. Moreover, each flower type was characterized as specially associated with two RAPD bands. UPGMA dendrograms based on RAPD and AFLP data, showed the majority of the cultivars from flower type I and flower type II clustering together. Finally 101 RAPD markers and 220 AFLP markers were used to construct a neighbor-joining dendrogram. This showed that the 37 cultivars could be classified into six distinct clusters, between which the similarity coefficient was as low as 0.00–0.55, even though the cultivars were morphologically very similar. The remaining two cultivars namely ‘Smathers’ and ‘Maltby’ were found genetically very distant from the other cultivars in RAPD, AFLP or combined RAPD and AFLP based dendrograms. The results suggested that the level of genetic variation among white sapote cultivars is diverse and the morphological and molecular data may lead to representation of the cultivar relationships as well as flower type discrimination.     

Genetic Relationship of Iranian Pear Genotypes with European and Asian Pears as Revealed by Random Amplified Polymorphic DNA Markers

Genetic variation within specific fruit tree germplasms is an important tool in fruit tree breeding programs. In the present work, the genetic relationship of 31 European and Iranian (Pyrus communis L.) and Asian (Pyrus serotina Rehd) genotypes of pear were studied using 19 randomly amplified polymorphic DNA (RAPD) primers. Fifteen out of the 19 primers used in this study amplified 3373 clear and reproducible bands associated with 150 loci and many of them were polymorphic. The dendrogram resulting from the unweighted pair-group method of arithmetic cluster analysis separated the cultivars into eight groups. The correlation coefficient between the cophenetic matrix and the similarity matrix was 0.82 (r = 0.82). There was a significant difference between populations and most studied genotypes clustered closely together based on their geographic origin and Iranian pears placed between two groups of pears. Results showed the suitability of RAPD analysis in genetic diversity study of pear.     

Assessment of genetic variation among thornless blackberries (Rubus spp.) using random amplified polymorphic DNA

Summary

To assess genetic relatedness in thornless blackberry (Rubus spp.), 11 different blackberry cultivars were screened using random amplified polymorphic DNA (RAPD) markers. The blackberries selected represented four different thornless backgrounds. Genetic similarity was estimated using 140 random primers, and the cluster analysis conducted using the RAPD data grouped the cultivars into three distinct clades. Ninety-eight primers produced 113 cultivar-specific RAPD fragments capable of identifying each cultivar. In addition, reproducible polymorphism using two primers was observed within the ‘Evergreen’ (R. laciniatus) clade that consisted of the pure thornless blackberry ‘Everthornless’, the chimeral ‘Thornless Evergreen’, and their thorny progenitor ‘Evergreen’. All three plants are believed to be identical, except for a single mutational event that caused the phenotypic change from thorny to thornless. The R. laciniatus RAPD marker data provide information that may eventually be useful to identify the gene(s) responsible for thornlessness in that species.     

Genetic diversity analysis of ginger (Zingiber officinale Rosc.) germplasm based on RAPD and ISSR markers

A global collection of ginger germplasm consisting of 46 accessions were characterized using two types of molecular markers, RAPD (Random Amplified Polymorphic DNA) and ISSR (Inter Simple Sequence Repeats). UPGMA dendrograms constructed based on three similarity coefficients, i.e., Jaccard's, Sorensen–Dice and Simple Matching using the combined RAPD and ISSR markers placed the accessions in four similar clusters in all the three dendrograms revealing the congruence of clustering patterns among the similarity coefficients and a rather less genetic distance among the accessions. Improved varieties/cultivars are grouped together with primitive types. Moreover, in the clustering pattern of the accessions, a geographical bias was also evident implying that germplasm collected from nearby locations especially with vernacular identity may not be genetically distinct. The clustering of the accessions was largely independent of its agronomic features.     

Identification of culinary rhubarb (Rheum spp.) cultivars using morphological characterization and RAPD markers

Summary

Twelve morphological traits and 47 RAPD (Random Amplified Polymorphic DNA) markers were used to discriminate twelve culinary rhubarb (Rheum spp.) cultivars and to estimate their genetic relatedness. Considerable variability was found among the cultivars analysed. Based on the two types of traits, cluster analyses and multidimensional scaling analyses were performed, resulting in a partly overlapping pattern of relatedness among cultivars. A Mantel correspondence test showed a moderate correlation (r = 0.41) between morphology and molecular markers. Since the development of culinary rhubarb cultivars is not well documented, there is no proper pedigree information for most of the cultivars. However, when comparing our results on morphology and RAPDs with pedigree information for four cultivars, a combination of the two types of data sets appeared to give fairly good information about relatedness among cultivars.     

15个樱桃品种的RAPD分析

利用RAPD技术,用104条随机引物对甜樱桃的14个品种和中国樱桃的1个品种进行遗传多样性分析,其中有14条引物的多态性较好。用任意一条能出现扩增带的引物,能明显区分开中国樱桃和甜樱桃,RAPD标记能够准确地进行种间的区分;而用一个引物或两个引物的组合只能鉴定出甜樱桃的一个品种。聚类结果显示,中国樱桃和甜樱桃的遗传距离最远;黄色果肉的养老和其他红色果肉的品种遗传距离较远。RAPD分析基本能够反映甜樱桃品种间的遗传多样性,但效果不理想,鉴定品种较为困难。     

茄子耐盐种质亲缘关系的RAPD分析

利用RAPD标记对14份耐盐茄子种质资源进行遗传多样性分析。结果表明：从100个引物中筛选出10个多态性较好的引物,共扩增出102条带,多态性条带所占的比例为77.45%。聚类分析结果显示：14份耐盐茄子材料的遗传相似系数在0.316～0.975之间|在遗传相似系数0.47处可将14份耐盐茄子材料分为3大类,大部分种质资源（85.71%）都聚在第3类（栽培种）,表明收集到的茄子耐盐种质亲缘关系较近。     

Genetic diversity and relationships of lotus (Nelumbo) cultivars based on allozyme and ISSR markers

Genetic diversity and genetic relationships of lotus (Nelumbo Adanson) cultivars were evaluated using allozyme and ISSR markers. The samples used covered 11 accessions of possible hybrids between Nelumbo nucifera and Nelumbo lutea and 92 accessions of N. nucifera including 69 flower lotus, 13 rhizome lotus, 5 seed lotus and 5 wild lotus. For allozyme studies, a total of 31 alleles at 23 loci of 18 enzyme systems were detected of which 5 (21.7%) loci Aat, Idh, Mdh-2, Pgd, Sod were polymorphic. The loci of Aat and Idh included two alleles, Mdh-2, Pgd and Sod included three alleles. Eighteen genotypes were detected with the 13 alleles of the 5 polymorphic loci. The parameters of average allele number, observed heterozygosity, expected heterozygosity and Shannon information index of 92 N. nucifera samples were 1.35 ± 0.71, 0.06 ± 0.21, 0.05 ± 0.14, 0.10 ± 023, respectively. Thirteen ISSR primers generated 93 loci, of which 37.63% were polymorphic across all samples. The percentage of polymorphic loci, average allele number, expected heterozygosity and Shannon information index of 92 N. nucifera samples were 26.67%, 1.30 ± 0.46, 0.10 ± 0.18 and 0.15 ± 0.25, respectively for the ISSR data. The ‘Bottleneck effect’ and rapid propagation of clones after the ice ages may explain the low genetic diversity of lotus. The dendrograms based on ISSR and allozymes were not congruent. Based on the ISSR data, the 103 samples were divided into the N. nucifera group (Group I), and the group containing inter-specific hybrids between N. nucifera and N. lutea (Group II). The flower lotus, rhizome lotus, and seed lotus each has multiple sources of origin. Plant size, a criterion commonly used in the classification of cultivars of lotus, is not correlated with genetic variation. Flower color is correlated with the cultivar classification to some degree, but its variation is complex in the hybrids.     

Suitability of isozyme,RAPD and AFLP markers to assess genetic differences and relatedness among fig (Ficus carica L.) clones

Sarilop is the main and standard cultivar for commercial dried fig (Ficus carica L.) production in Turkey. Eleven of the most promising Sarilop clones and one clone of Sarizeybek, all selected from a former agronomic evaluation, were analysed by three molecular marker techniques, isozymes, RAPDs and AFLPs. The resolution power and the accuracy of these three analytical techniques, in distinguishing among fig clones, were determined. The analysis of five isozyme systems permitted the discrimination between the two cultivars, Sarilop and Sarizeybek. Besides the discrimination between the two fig cultivars, the use of 31 10-mer primers in RAPD analysis allowed splitting the 11 Sarilop clones into two groups of genetic similarity, but not to distinguish between all the clones. The AFLP™ technology showed a much higher multiplex ratio than the RAPD technique (42.4 vs. 6.1) and eight combinations of EcoRI/MseI primers were enough to clearly distinguish between all the Sarilop clones.     

DNA fingerprinting and genetic diversity analysis of late-bolting radish cultivars with RAPD,ISSR and SRAP markers

Three molecular marker systems, RAPD (random amplified polymorphic DNA), ISSR (inter-simple sequence repeat) and SRAP (sequence-related amplified polymorphism), were employed for identification and genetic diversity analysis of 35 elite late-bolting radish cultivars. Detected by 35 RAPD primers, 22 ISSR primers and 17 SRAP primer combinations, the proportions of polymorphic bands were 85.44%, 85.2% and 85.41%, respectively, and the mean genetic similarity coefficients between pairs of genotypes were 0.781, 0.787 and 0.764, respectively. Each of the three molecular marker systems can identify all the cultivars. Five sets of three-RAPD primers, 3 sets of three-ISSR primers and 16 sets of three-SRAP primer combinations were able to distinguish all the cultivars. A linear relationship was observed between Resolving power (Rp) of a primer and its ability to distinguish genotypes. The 35 cultivars were clustered into three major groups based on the RAPD, ISSR and marker combination data with UPGMA, which are in high accordance with their own origins and main characteristics. The results demonstrated that these three marker systems could be useful for identification and genetic diversity analysis of radish cultivars.     

十二个油松种群遗传多样性的RAPD分析

运用RAPD分子标记技术,对12个油松天然居群中192个单株进行遗传多样性分析。用筛选出的20条引物共扩增出289个条带,其中多态性条带220个,多态性条带百分率为76.12%。用NTSYS-PC软件计算遗传相似性系数进行聚类分析。结果表明:192份油松材料间的SC值变化范围为0.5986～0.9654,平均为0.7379。采用UPGMA法,在SC值为0.76的水平上可将供试材料聚为3类。表明我国油松天然种群间产生一定程度的变异,在分子水平上呈现出遗传多态性。     

An assessment of genetic variability and relationships within Asian pears based on AFLP (amplified fragment length polymorphism) markers

A total of 100 Pyrus L. accessions native mainly to East Asia were subjected to amplified fragment length polymorphism (AFLP) analysis to evaluate genetic variability and relationships among the accessions. Six AFLP primer combinations produced a total of 459 fragments, of which 410 were polymorphic with a polymorphism percentage of 89%. The Dice's similarity coefficient among pear accessions ranged from 0.671 (P. betulaefolia Bge and P. elaeagrifolia Pall.) to 0.947 (‘Umajirou’ and ‘Immuraaki’). Occidental pears generally had low similarities to Asian pears. The dendrogram generated from all the accessions by unweighted pair-group method of arithmetic analysis (UPGMA) cluster analysis clearly distinguished Occidental pears from accessions of East Asia. P. ussuriensis Maxim., P. betulaefolia and P. communis L. clustered separately into independent groups in accordance with their morphological classification. Japanese pear cultivars formed two groups with some Chinese white pears and Chinese sand pears. Chinese white pears and Chinese sand pears independently formed their own groups and also mingled into mixed groups in the dendrogram. Therefore, Chinese white pears were treated as a cultivated group or an ecotype of P. pyrifolia: P. pyrifolia White Pear Group. The information obtained from this study will be of great help for understanding the origin and evolution of Asian pear cultivars.     

杧果种质遗传多样性的RAPD分析

对杧果不同生态型、不同胚性、不同果形与果色的38份品种和1个近缘种—扁桃进行了RAPD分析,19个引物在39份种质中共扩增出223条带,其中多态性带为196条,多态性带的百分率为87.89%,表明品种间存在着广泛的遗传基础。利用UPGMA进行聚类分析,在相似性系数0.755的水平上将38个品种分成3组,该结果与传统上以胚型为依据进行品种类群划分比较吻合。发现了多个与胚性密切相关和1个与果皮颜色密切相关的RAPD标记,并就部分品种的系谱关系、胚性和果皮颜色的遗传进行了探讨。     

Molecular assessment of polymorphism among local Jordanian genotypes of the common fig (Ficus carica L.)

This research was conducted to assess polymorphism among local genotypes of common fig available in Jordan (one of countries of origin). Leaf samples were collected in spring for DNA isolation from 20 different local genotypes (5 cultivars and 15 landraces). Two more wild types and one foreign cultivar were included. The genotypes were assessed using the randomly amplified polymorphic DNA (RAPD) technique. Six of the 19 screened primers showed reproducible polymeric profiles. Out of 62 amplified bands, 48 were polymorphic (77%). They generated 1104 data entries (591 for present and 513 for absent bands). After determining Jaccard similarity index, some genotypes showed high genetic similarity (90% between F20 and F22), while other were less similar (3–18% between F11 and all other genotypes). Moreover, the primers were evaluated for their discriminating power, where primer RAPD06 showed the weakest power (0.431), while highest values of 0.989 and 0.996 were achieved for primers RAPD02 and RAPD13, respectively.     

RAPD技术在石榴品种分类上的应用

以55个石榴栽培品种为试验材料,利用15条多态性好的随机引物进行RAPD分析,共扩增出125条带,其中多态性条带92条,多态性百分率73.6%,说明品种间有变异。应用TFPGA软件计算55个石榴品种间的Nei’s遗传距离,并用UPGMA法构建聚类图,将55个石榴品种分为4个类群,从DNA水平上揭示了石榴品种之间的亲缘关系。结果表明,采用UPGMA法聚类的结果与形态上的分类存在着一定的差异,即与根据花色和果味进行的分类没有相关性而与瓣型进行的分类有一定的相关性。     

Molecular systematics in Chrysanthemum × grandiflorum (Ramat.) Kitamura

An attempt was made to understand the molecular systematics and genetic differences between 10 original chrysanthemum cultivars and 11 mutants. The similarity among the cultivars and mutants varied from 0.17 to 0.90 using RAPD analyses, a simple but efficient method to distinguish cultivars and to assess parentage. Two distinct groups were found. Two cultivars were present as a separate group showing differences from all other cultivars. Mutants with different flower colour could be identified at the molecular level using RAPD technique holding promise to identify unique genes as SCAR markers. A high genetic distance among the different chrysanthemums showed that there exists a possibility of introgressing new and novel genes from the chrysanthemum gene pool.