基于内部简单重复系列(ISSR)分析的当归分子鉴定

目的利用内部简单重复系列（ISSR）分子标记技术,对药用当归及其混伪品进行鉴别。方法利用简单重复序列区间扩增（ISSR-PCR）方法对采集和购买的26份当归及其混伪品进行基因组多态性分析;采用NTSYS-pc version 2.10e软件计算各供试材料间的遗传相似系数,分析其亲缘关系并构建聚类图。结果从100条内部简单重复系列引物中筛选出10条多态性好,稳定性高的引物对所有材料进行扩增,共获得96条带,扩增片段大小介于200~2 100 bp之间,多态性条带85条,占总扩增片段的88.54%。引物UBC848能扩增出1条当归的特异性条带。引物组合UBC848和UBC834可以将正品当归与其混伪品材料区分开来。UPGMA聚类分析表明,9个不同产地的当归聚为一类,与日本当归间的亲缘关系较近,而其余当归属和伞形科植物与当归聚类较远。市售3个未鉴别品种,均为当归伪品。结论本实验根据内部简单重复系列技术分析找到了当归及其混伪品间的特异鉴别引物,4条引物能反应不同来源当归间存在遗传多样性。本结果为当归的鉴定提供了分子依据,为建立稳定的当归质量评价体系提供技术支持。

同名甘蓝型油菜品种比较分析

为评价不同来源同名甘蓝型油菜品种的异同性,以42个同名甘蓝型油菜品种(共91份)为研究对象,采用同名品种两两相邻种植方法,分成56组,调查参试品种的29个DUS[特异性(distinctness)、一致性(uniformity)和稳定性(stability)]测试性状,并采用43个SSR标记,对参试品种进行指纹分析,进而比较同名甘蓝型油菜品种基于DUS测试性状和SSR标记的异同性。结果表明,39.3%(22组)的不同来源同名品种无论是表型还是SSR标记都存在较大差异;26.8%(15组)的同名品种间表型和SSR指纹极为相似,亲缘系数表明,该类品种亲缘关系密切;只有33.9%(19组)的同名品种综合表现为无明显差异。由此可知,不同来源的甘蓝型油菜品种中,同名异种现象比较普遍,建议相关主管部门加强对同名品种的管理。

蒙药“阿给”不同居群遗传多样性的ISSR分析

目的研究内蒙古地区草甸草原、典型草原及森林草原中蒙药阿给的遗传多样性。方法利用12条ISSR引物对3个阿给居群进行扩增,用PopGen 32进行数据计算与聚类分析。结果 ①12条引物共扩增出184个位点,其中多态性位点为180,多态位点百分率为97.83%。②3个居群Gst=0.043 0,基因流Nm=11.135 5。③通过UPGMA分析,典型草原与森林草原阿给居群聚为一类,草甸草原阿给居群单独聚为一类。结论 ①阿给具有丰富的遗传多样性。②阿给居群总的遗传多样性大部分存在于居群内,各居群间有基因交流。③典型草原居群与森林草原居群的遗传距离最小,草甸草原居群与典型草原居群的遗传距离最大,这可能与其地理位置的远近有关。

SSR分子标记技术在入侵昆虫学研究中的运用

外来入侵生物通过与本地生物竞争营养、水分和生存空间,造成严重的生态破坏和生物污染,最终导致生物多样性的丧失,逐渐成为人类生存和社会可持续发展的新威胁。简单序列重复(simple sequence repeats,SSRs)或微卫星DNA(microsatellites DNA)分子标记是生物群体遗传结构分析与变异研究中极有价值的分子标记,由于其具有多态性检出率高、信息含量大、共显性标记、实验操作简单、结果稳定可靠等优点,目前在外来入侵生物研究中得到广泛应用。本文概述了SSR分子标记在入侵昆虫来源鉴定、杂交和基因渗透、瓶颈效应等方面的应用进展,并对其在入侵生物学中的应用前景进行了展望。

Taxonomic Status of Daduhe Loquat （Eriobotrya prinoides var. dadunensis）

The taxonomic status of Daduhe loquat （E. prinoides var. dadunensis） was studied through analyzing genetic relationships among Oakleaf loquat （E. prinoides）, Daduhe loquat and Common loquat （E. japonica） using inter simple sequence repeats （ISSR） molecular marker and morphologic marker in this paper. Based on ISSR marker research, the similarity coefficient between Oakleaf loquat and Common loquat was lower than the similarity coefficient between Oakleaf loquat and Daduhe loquat while the similarity coefficient between Daduhe loquat and Common loquat was intermediate. The highest additivity was obtained when Daduhe loquat was regarded as the undetermined hybrid （45.8%）. The specific bands of Oakleaf loquat and Common loquat were present in Daduhe loquat. Based on morphologic traits research, Daduhe loquat was also between Oakleaf loquat and Common loquat but a little leaning to Oakleaf loquat. All the results support that Daduhe loquat was hybrid of Oakleaf loquat and Common loquat.

Discriminating ability of molecular markers and morphological characterization in the establishment of genetic relationships in cultivated genotypes of almond and related wild species

A total 23 morphological traits, 19 AFLP-primer combinations, 80 RAPD primers and 32 SSR primer pair were used to compare the informativeness and efficiency of random amplified polymorphic DNA (RAPD), amplified fragment length polymorphism (AFLP) and simple sequence repeat (SSR) markers in establishing genetic relationships among 29 almond cultivars and three related wild species. SSRs presented a high level of polymorphism and greater information content, as assessed by the expected hetrozygosity, compared to AFLPs and RAPDs. The lowest values of expected hetrozygosity were obtained for AFLPs; however AFLPs showed the highest efficiency, owing to their capacity to reveal large numbers of bands per reaction, which led to high values for various types of indices of diversity. All the three techniques discriminated almond genotypes very effectively, except that SSRs failed to discriminate between ‘Monagha’ and ‘Sefied’ almond genotypes. The correlation coefficients of similarity were statistically significant for all the three marker systems, but were lower for the SSR data than for RAPDs and AFLPs. For all the markers, high similarity in dendrogram topologies was obtained, although some differences were observed. All the dendrograms, including that obtained by the combined use of all the marker data, reflect relationships for most of cultivars according to their geographic diffusion. AMOVA detected more variation among cultivated and related wild species of almond within each geographic group. Bootstrap analysis revealed that the number of markers used was sufficient for reliable estimation of genetic similarity and for meaningful comparisons of marker types.

Molecular Markers Associated with Starch Content and Implications for Sugarcane Introgression Breeding Using Saccharum spontaneum

Introgression with Saceharum spontaneum intended to broaden the genetic base of sugarcane resulted in an increase in desirable genes for broader adapt ability as well as undesirable genes for high starch content. Markers could provide a quick and efficient method of screening parental genotypes for low starch. The objectives of this study were to identify potential markers associated with starch in S. spontaneum population and evaluate their potential for screening for starch content. Data for starch content and （simple sequence repeats） SSR markers were collected from 51 S. spontaneum clones grown in replicated pots. The mixed procedure of statistical analysis system （SAS） was used to determine markers significantly associated with starch. Thirty-nine out of 357 polymorphic markers were significantly （P 〈 0.05） associated with starch content. Eighteen were positively associated and 21 were negatively associated. The presence of a positive marker produced 39% more starch than absence while the absence of a negative marker produced 57% more starch than presence. Selecting parents using negative markers may be more efficient than selecting using positive markers.

数据库搜索及ISSR-抑制PCR法开发香菇微卫星标记

采用数据库搜索及ISSR-抑制PCR法开发香菇微卫星标记。由数据库搜索法开发出21对引物,11对有多态性,各位点平均产生3.3个等位基因;通过ISSR-抑制PCR法开发出8对引物,5对具多态性,各位点平均产生3个等位基因。结果表明,在香菇SSR开发中,两种方法均是行之有效的。

四大家鱼的ISSR标记研究

采用ISSR分子标记技术对4种重要经济鱼类青鱼、草鱼、鲢鱼、鳙鱼进行了研究,从100个引物中筛选出了适合4种鱼的17个引物,这些引物都扩增出清晰稳定并且可重复的条带。扩增结果显示,17个引物都为二碱基重复序列,引物锚定碱基位于3’端。17个引物中仅840和842引物对4种鱼都能扩增出清晰条带,但扩增图谱存在一定的差异。