杏鲍菇多孢分离菌株ISSR、RAPD分子标记及体细胞不亲和性分析

通过杏鲍菇多孢分离菌株的ISSR、RAPD分子标记和体细胞不亲和性分析,体细胞不亲和性分析得出子代杏1、杏3、杏4与出发菌株湘杏98有拮抗线,杏1、杏2、杏3、杏4四株子代均有明显的拮抗线。16条ISSR引物和19条RAPD引物分别扩增出99、154个条带,多态性条带分别占48.48%、61.00%;相似系数变异范围分别为0.63~0.86、0.57~0.83。湘杏98、杏2、杏3在2种标记的聚类结果上存在差异。体细胞不亲和性分析从表型上(拮抗线有无)反应了菌株的遗传变异。RAPD标记遗传相似系数小于ISSR标记,表明ISSR标记更适合亲缘关系较近的种群间遗传多样性分析。     

ISSR标记在芋遗传多样性研究中的应用前景

ISSR是在SSR基础上发展起来的一种分子标记技术,兼具SSR、RAPD、RFLP、AFLP等分子标记的优点。对运用形态学和分子生物学手段研究芋的遗传多样性进展进行了综述,并对ISSR分子标记技术在芋种质资源遗传多样性和亲缘关系、种质资源鉴定和指纹图谱构建、基因定位和分子标记辅助选择等方面的应用前景做出了分析和展望。     

不同金针菇菌株多相分类研究

利用菌丝拮抗反应、酯酶同工酶以及ISSR分子标记对35个金针菇菌株进行多相分类研究,建立了遗传相似性聚类分析图。结果表明:拮抗反应与ISSR分析结果较为一致,而酯酶同工酶与拮抗反应、ISSR分析结果差异较大,ISSR聚类分析结果更为精确。根据ISSR聚类分析,当相似系数为0.86时,可将供试菌株分为7组,其中黄色金针菇的遗传多样性要高于白色金针菇。     

野生天门冬遗传多样性的ISSR分析

通过ISSR技术对19个野生天门冬居群共67个个体进行遗传多样性分析.结果表明:用13个随机引物共扩增出125条清晰条带,其中92条具多态性,平均多态性位点比率为73％,建立了不同居群的ISSR标记;Nei's基因多样性指数H=0.19,Shannon,s多样性指数I=0.30,遗传分化指数Gst=0.8206.聚类分析表明,青海、云南和贵州省的5个居群聚为一大支,其它居群为另一大支.野生天门冬种内具有较高的遗传多样性,遗传变异主要存在于居群间;ISSR标记可以作为研究天门冬遗传多样性及居群鉴定的有效标记.     

ISSR分子标记技术及其在园艺作物中的应用分析

在生物科学领域中,ISSR是一种以微卫星序列为基础的新型分子标记。在实际应用中,其具有DNA多态性高、稳定高效、简单迅速等优势。ISSR的遗传形式属于孟德尔式,主要以显性标记为主。ISSR能够在SSR3′、5′端,增加锚1~4个嘧啶碱基或嘌呤,使特定位点退火,进而让引物和匹配SSR一端相结合,进而实现基因组特定片段的检测和扩增。目前,在园艺作物领域中,ISSR分子标记技术具有广泛的应用,主要包括品种纯度鉴定、分子标记辅助育种、基因定位、遗传图谱构建、遗传多样性研究等方面。     

基于ITS和ISSR标记的灵芝遗传多样性和群体结构分析

以来自不同地理区域的48个灵芝种质资源为试材,采用ITS和ISSR分子标记的方法,研究了灵芝遗传多样性,以期利用遗传信息数据较理想地显示出不同灵芝菌株的遗传多样性。结果表明：通过进行ITS序列扩增测序,将48个灵芝菌株分为赤芝(35个)、无柄灵芝(11个)、四川灵芝(1个)、古巴栓孔菌(1个)。5条ISSR引物共扩增得到53条条带,多态性条带比率为96.23%,Nei′s基因多样性为0.27,Shannon′s信息指数为0.43。ISSR标记遗传相似系数约为0.70,将48个灵芝菌株分为3组,其中第1组为11个无柄灵芝,第2组为菌株29“盆景1”,其他菌株为第3组,说明2种标记结合分析能够更加准确分析不同菌株间的亲缘关系。菌株16和17同为赤芝,且ISSR分子标记遗传相似系数达0.98,推测可能为同一品种,为生产中出现的同物异名现象。该研究选取的用于PCR扩增的ISSR引物,多态性较好、稳定性较高,能有效鉴别出无柄灵芝与其他灵芝,并揭示种质的遗传多样性和群体遗传结构,可为灵芝种质资源保护及优质种质材料选育提供参考依据,以期更好地推动灵芝产业健康发展。     

ISSR技术在食用菌研究上的应用

ISSR分子标记是一种基于SSR基础上发展起来的新技术,具有很好的稳定性和多态性,且有操作简便、安全,成本低等特点。该研究回顾了ISSR分子标记在食用菌的遗传多样性、杂交育种、品种鉴定等方面的研究进展,指出其对菌种改良、保护菌种资源、规范食用菌市场管理等有重要的作用。在未来的工作中,不断改进现有的ISSR技术,并与其它分子标记技术结合应用,是发展食用菌分子水平研究的需要。     

分子标记在濒危植物遗传多样性研究中的应用

介绍微卫星DNA标记、RFLP分析、RAPD分析、AFLP分析、ISSR分析的基本原理及其在濒危植物遗传多样性研究中的应用，并对这些分子标记手段的优缺点进行了比较。     

ISSR分子标记技术在园林植物中的应用

主要从遗传多样性研究、亲缘关系与分类学研究和种质资源鉴定研究3个方面介绍了ISSR分子标记在园林植物中的应用,并探讨其存在的问题。     

48 份分蘖洋葱种质资源遗传多样性的ISSR 标记和农艺性状分析

对来自黑龙江省和吉林省不同地区的48 份分蘖洋葱资源的遗传多样性进行了ISSR 标记及农
艺性状观测分析。从51 条ISSR 引物中筛选到13 条多态性高、扩增稳定、重复性好的引物,这13 条引
物共扩增出132 个位点,其中109 个多态位点;应用Nei-Li 相似系数法估算了48 份材料间的遗传相似系
数,结果表明,48 份分蘖洋葱遗传相似系数变化范围在0.59 ～ 0.94 之间。对分蘖洋葱的抽薹情况、幼叶
色、鳞茎色和单球质量进行了调查,结果表明,48 份分蘖洋葱遗传相似系数变化范围在0.38 ～ 1.00 之间。
ISSR 标记和农艺性状分析均表明48 份分蘖洋葱的遗传多样性较丰富;两种方法的聚类结果基本一致,聚
类结果与地理分布有明显的联系。     

巨大革耳遗传多样性的ISSR分析

为确定巨大革耳种质资源问的亲缘关系,本文应用ISSR分子标记技术,对来源不同地区的野生或栽培的9个巨大革耳菌株进行遗传多样性分析。从20个引物筛选获得4个ISSR多态性引物对巨大革耳菌株扩增,获得23条多态性条带,多态性比率为85．19％;对扩增结果进行聚类分析,当遗传距离为20％时,9个菌株聚为2类：I类包括C．m0002菌株;Ⅱ类包括其它的8个菌株。其中C．m0002菌株与其它8个菌株的遗传距离很远。经栽培出菇实验,结果表明,C．m0002菌株的子实体似多脂鳞伞（黄伞）,是同名异种;其它8个菌株均为巨大革耳。ISSR分析的结果与子实体形态特征一致。     

豆瓣菜种质资源遗传多样性的RAPD和ISSR分析

以8个豆瓣菜的品种为试材，用筛选出的79个RAPD引物和34个ISSR引物对这8个品种的基因组DNA进行扩增，分别扩增出361条和179条谱带，每个引物扩增出的带在3～10条之间，平均每个引物扩增出约5条带。根据所得的条带进行聚类分析，两种标记产生的聚类图存在一些差异，但它们都可以较好地将8个品种按亲缘关系的远近划分为3个不同的类群。Mantel测试得出相关系数r=0．58155，表明RAPD和ISSR两种分子标记技术的相关度很低。     

Genetic variability in wild vs. cultivated Eruca vesicaria populations as assessed by morphological,agronomical and molecular analyses

In this study, the genetic diversity of 50 individuals of rocket, Eruca vesicaria, from five accessions, four of them wild type collected from different parts of Spain and one commercial, were evaluated using morphological, agronomical and inter simple sequence repeat DNA (ISSR) data. Molecular analysis was carried out using the ISSR technique with 20 primers. Out of these 20 primers, nine were polymorphic, producing a total of 395 DNA bands, 247 of which were polymorphic among the accessions. A dendrogram drawn on the basis of a similarity matrix using the UPGMA algorithm revealed that the 50 samples of rocket plants could be classified into three major clusters at a Nei's genetic distance of 0.36. The experiment shows that molecular markers such as ISSR are a good instrument for distinguishing and selecting rocket accessions to group different wild populations. In general, a high variation was observed for most of the 16 morphological and 6 agronomical traits showing significant differences. Some morphological traits such as leaf length, petiole length and lamina width explained 69.1% of the whole variation observed in the populations, and some agronomical traits such as leaf area, nitrate and chlorophyll contents accounted for 65.7%, but the clusters generated by means of agronomical and morphological variables were less evident than when ISSR markers used. Some accessions showed good qualities, such as small leaves, high chlorophyll content, late-flowering or low nitrate content. All these parameters, together with the high degree of genetic homogeneity found, could make the local accessions good candidates for a future breeding programme.     

Assessment of clonal fidelity of micropropagated gerbera plants by ISSR markers

True-to-type clonal fidelity is one of the most important pre-requisites in micropropagation of crop species. Genetic fidelity of in vitro raised 45 plants of gerbera (Gerbera jamesonii Bolus) derived from three different explants, viz., capitulum, leaf and shoot tips, was assessed by 32 ISSR markers, for their genetic stability. Out of 32 ISSR markers, 15 markers produced clear, distinct and scorable bands with an average of 5.47 bands per marker. The markers designed from AG motif amplified more number of bands. The markers anchored at 3′ ends produced high number of consistent bands than unanchored markers. Fifteen ISSR markers generated a total of 3773 bands, out of which 3770 were monomorphic among all the clones. The Jaccard's similarity coefficient revealed that out of 45 clones derived from different explants, 44 were grouped into a single large cluster alongwith the mother plant with a similarity coefficient value of 1.00, whereas one clone (C38) remained ungrouped. The clones derived from capitulum and shoot tip explants did not show any genetic variation, whereas, one of the leaf-derived clones exhibited some degree of variation.     

菠萝蜜遗传多样性的ISSR分析

用ISSR标记方法对76份菠萝蜜(Artocarpus heterophyllus Lam.)种质资源DNA的遗传多样性进行了检测,24个引物共检测到477条带,其中427条具多态性(占89.52%),平均PIC为0.23,24个引物能把76份种质完全区分开来。遗传距离分析结果显示供试种质的遗传多样性较低,在DNA水平上的遗传相似系数为0.626～0.945,平均为0.775。聚类分析表明,76份菠萝蜜材料在遗传距离系数为0.752处可分为4大类,其中热带植物园的种质WJ2和GSYWJ1与其他种质的遗传距离相对较大,干胞和湿类型不能独立聚类。另外各地区的种质与雷州半岛种质明显分开聚类,而雷州半岛各地区的种质混杂聚类在一起,不能按地区单独聚类。     

苹果柱型基因的ISSR分子标记研究

 以普通型苹果品种‘富士’和柱型苹果‘舞姿’以及其杂交后代的柱型与非柱型实生苗为试材, 建立了苹果的ISSR ( Inter-Simple Squence Repeat polymorphic DNA) 分子标记体系, 并将ISSR 标记用于苹果柱型基因Co 的遗传分析。结果表明, 在20μL 反应体系中各组分的用量为Taq DNA 聚合酶1U、Mg²⁺ 的浓度为2.5 mmol·L^-1 、模板DNA 用量20 ng、引物浓度0.2μmol·L - 1及退火温度52 ℃, 80 %引物具有良好的扩增能力。调整模板DNA 的用量、引物浓度及退火温度能够优化苹果ISSR-PCR 扩增体系。从所筛选的65 个引物中获得了35 个ISSR 标记, 其中33 个标记呈现1∶1 分离, 可用于苹果柱型基因的遗传分析。     

Phylogenetic study and molecular identification of 31 Dendrobium species using inter-simple sequence repeat (ISSR) markers

The genetic diversity of the genus Dendrobium is not well known and the phylogenetic relationship of Dendrobium species are mainly determined by studies of the comparative vegetative anatomy and plant systematics. In the present study, we used the technique of inter-simple sequence repeats (ISSRs) to evaluate genetic diversity and phylogenetic relationship among 31 Dendrobium species from Yunnan region of China. In total, 2368 bands were amplified by 17 ISSR primers, resulting from 278 ISSR loci with 100% polymorphism at genus level. Thirty-one species were unequivocally distinguished based on ISSR fingerprinting. Species-specific ISSR markers were identified in nine of 31 tested Dendrobium species. Unweighted pair-group mean analysis (UPGMA) showed that 31 Dendrobium species were grouped into six clusters, indicating the genus was polyphyletic with several well-supported lineages. The high polymorphism and reliable amplification across species demonstrated the utility of ISSR marker for species diagnosis and genetic diversity study of the genus Dendrobium.     

Genetic diversity and classification of Nelumbo germplasm of different origins by RAPD and ISSR analysis

In this study, RAPD and ISSR markers were used to investigate the genetic diversity and genetic relationships among different germplasm of Nelumbo including 70 Chinese ornamental cultivars, 7 wild Thai genotypes, 2 Nelumbo lutea genotypes and 8 hybrids of Nelumbo nucifera and N. lutea. High genetic diversities of 96.4% and 91.2% respectively were detected in the Nelumbo accessions using RAPD and ISSR markers. A dendrogram based on both RAPD and ISSR clustering data indicated that: (1) the genotypes of N. nucifera and N. lutea from different geographical origins were clustered into different groups. This indicated significant genetic differentiation attributed to extensive periods of geographical isolation and lack of gene exchange; (2) the Thai wild genotypes were separated from Chinese genotypes. This indicated genetic divergence between germplasm from Southeast Asia and that from China. Geographical location appears to have affected genetic diversity due to adaptation of the plants to the different environments. A new Southeastern Asia Lotus category is suggested as an addition to the current lotus cultivars classification system; (3) data on three morphological traits (namely: plant size, petal shape and flower color), showed that only the data on plant size was consistent with the dendrogram constructed from molecular data. This finding suggests that using data on genetic relationships in combination with morphological characteristics would serve to improve the classification system of lotus cultivars currently in use. The finding of previously unknown germplasm in this study indicated the potential of RAPD and ISSR techniques in identifying and managing lotus resources. Both marker techniques are potentially useful in improving the current strategies in breeding and germplasm conservation to enhance the ornamental and economic value of lotus.     

Genetic structure of mulberry from different ecotypes revealed by ISSRs in China: An implications for conservation of local mulberry varieties

Mulberry is a perennial and economically important plant that has traditionally been used for feeding the silkworm. Evaluating genetic relationship is important for long-term improvement in mulberry yield, quality and resistance, and for germplasm conservation and identification. Population structure and genetic diversity of 8 mulberry populations from different ecotypes in China were analyzed by ISSR markers. Twelve ISSR primers generated a total of 83 amplification products, of which 50 were polymorphic, revealing 60.24% polymorphism among 66 mulberry local varieties, the mean PIC value was 0.1469. The total heterozygosity (H_T), heterozygosity within population (H_S), diversity between populations (D_ST) were 0.1600, 0.0851 and 0.0749, respectively. The coefficient of population differentiation (G_ST) was 0.4683, indicating that the variations among populations and those within populations contributed 46.8% and 53.2% to the total heterozygosity, respectively. The gene flow (N_m) was 0.5678, suggesting that genetic drift between populations can caused local genetic differentiation and therefore, population divergence. The mean genetic similarity coefficient was 0.8456, genetic similarity coefficient among 8 mulberry populations ranged from 0.8441 to 0.9640, indicating that genetic diversity of different populations existed variation. A dendrogram of all 66 local varieties of mulberry based on the genetic similarity using ISSR markers was generated by UPGMA cluster method. In the dendrogram, most varieties from the same ecotype clustered together.