四川重楼属植物地理分布新记录

报道了四川重楼属植物1新分布种和1新分布变种,分别是平伐重楼(Paris vaniotii H.Léveillé)和白花重楼(P.polyphyllavar.alba H.Li&R.J.Mitchell)。二者均为狭域分布和间断分布类群,平伐重楼在模式标本产地濒于灭绝,四川新分布的发现具有重要意义。     

湖南重楼属植物小志

通过多年的调查、标本采集和分类研究,初步查明湖南产重楼属植物5种、6变种和1变型。其中有2种（凌云重楼Paris cronquistii,北重楼Paris verticillata)、3变种（滇重楼Paris polyphylla var.yunnanensis,卵叶重楼Paris delavayi var.petiolata,长药隔重楼Paris polyphylla var.pseudothibetica)和1变型（宽叶重楼Paris polyphlla var.stenophylla f.latifolia)为湖南新纪录。同时,还记录了各种、变种和变型的简要特点、分布和生境,并列出了它们的检索表。     

应用RAPD标记分析黑麦属品种的遗传多样性

四川农业大学小麦研究所侯永翠、郑有良、魏育明等研究人员对黑麦遗传多样性课题作了研究。他们采用随机扩增多态性DNA(RAPD)标记 ,对黑麦属 (SecaleL) 7个品种共 1 2份材料进行了遗传多样性检测 ,发现被检测材料间RAPD标记多态性较高 ,在 4 0个随机引物中 ,有 2 5个引物约占整个的 6 2 .5 %的扩增产物具有多态性。这 2 5个中共扩增出 1 6 7条带 ,其中 89条带约占 5 3.2 %具有多态性 ,每个引物可扩增出 1～ 1 0条多态性带 ,平均为 3～ 6条。RAPD标记遗传距离GD变异范围为 0 .1 382～ 0 .4 5 1 2 ,平均为 0 .2 71 2。通过聚类分析表…     

4种红豆杉属植物遗传多样性和遗传关系的RAPD分析

采用RAPD标记研究了分属于4种红豆杉属(Taxus Linn.)植物的68个单株的遗传多样性,并采用UPGMA方法分析68个单株的遗传关系.结果表明:12条RAPD引物共扩增出109条带,其中多态性条带108条,多态性条带百分率为99.1％;平均每条引物扩增出9.1条带.南方红豆杉[T.wallichiana var.mairei (Lemée et Lévl)L.K.Fu et Nan Li.]种内的多态性条带百分率和观察等位基因数均最高;欧洲红豆杉(T.baccata Linn.)种内的有效等位基因数、Nei's基因多样度和Shannon's信息指数均最高;须弥红豆杉(T.wallichiana Zucc.)种内的各项遗传多样性指数均最低.供试4种植物的种内遗传多样度、种间遗传多样度、基因流和种间遗传分化系数分别为0.1745、0.358 6、0.401 7和0.554 5,表明55.45％的遗传变异发生在种间.南方红豆杉和须弥红豆杉遗传距离最近;曼地亚红豆杉(Taxus×media Rehd.)和须弥红豆杉的遗传距离最远.通过聚类分析可将68个单株分为3组,欧洲红豆杉的18个单株和曼地亚红豆杉的18个单株分别各自聚为1组;须弥红豆杉的16个单株和南方红豆杉的16个单株聚为1组,其中须弥红豆杉的16个单株和南方红豆杉的16个单株又各自聚为1个亚组,且南方红豆杉的雌、雄单株也分别聚在同一分支上,表明须弥红豆杉和南方红豆杉遗传关系较近,而欧洲红豆杉与其他3种植物的遗传关系较远.     

分子标记在百合属植物遗传多样性研究中的应用

介绍分子标记技术及其发展概况,并重点论述几种常见分子标记技术如随机扩增多态性DNA(random amplified polymorphism DNA,RAPD)、简单重复序列间区(inter-simple sequence repeat,ISSR)、扩增片段长度多态性(amplified fragment length polymorphism,AFLP)和内转录间隔区(internal transcribed spacer,ITS)等的基本原理、技术上的优缺点及其在百合属植物遗传多样性研究中的应用现状,同时对分子标记技术在百合属植物遗传多样性研究中的应用前景进行展望.     

多叶重楼遗传多样性的ISSR分析

采用ISSR分子标记对多叶重楼种下3个变种的8个居群共208份样品的遗传多样性进行了分析。l4条引物共检测到251个清晰的扩增位点,其中多态位点235个。在物种水平上,多态位点百分率(PPB)达93.63%,Nei′s基因多样性指数(HE)为0.2204、Shannon′s信息指数(HO)为0.3532。在居群水平上,多态位点百分率(PPB)为50.45%,Nei′s基因多样性指数(HE)为0.1405,Shannon′s信息指数(HO)为0.2194,这些均表明多叶重楼的遗传多样性水平较高。此外,还用NTSYS软件对样品进行了UPGMA聚类分析,结果显示滇重楼的6个居群聚为一支,滇重楼与狭叶重楼有较近的亲缘关系,而与长药隔重楼之间的遗传分化较大。本研究提出了合理保护重楼植物资源的若干措施,为进一步开展滇重楼优质种质引种驯化,实现种质资源多样性的合理保护和可持续利用提供参考。     

基于AFLP标记的山东省5个野核桃群体的遗传多样性分析

利用AFLP分子标记,对分布于山东省内5个样地(泰山鹁鸽崖、鲁山核心区边缘、崂山北九水、昆嵛山南天门和泰山佛爷寺)的46个野核桃(Juglans cathayensis Dode)单株的遗传多样性进行了分析,并采用聚类分析方法探讨了它们的遗传关系.结果表明:用8对PstI/ MseI系列引物组合从46个单株中共扩增出1 034条带,其中多态性条带1 005条,多态性条带百分率达97.20％;每对引物可扩增出113 ～ 154条多态性条带,平均每对引物可扩增出125.6条多态性条带.在这些条带中包含174条特异性条带(其中有19条缺失条带),通过特异性条带可鉴别出91.3％的野核桃单株.5个野核桃群体的多态性条带百分率(PPB)、观测等位基因数(Na)、有效等位基因数(Ⅳe)、Nei,s基因多样度(H)和Shannon's信息指数(I)分别为50.57％ ～ 63.51％、1.505 7～1.635 1、1.273 5 ～ 1.300 4、0.163 2～0.181 9和0.249 1 ～0.281 3,PPB、Na、Ne、H和I的平均值分别为55.23％、1.552 3、1.284 3、0.169 6和0.259 4,表明野核桃群体遗传多样性较高、遗传变异较为丰富.46个单株的遗传相似性系数为0.536 8 ～0.8645,平均值为0.624 9.聚类分析结果显示:在遗传相似性系数0.66处,可将46个单株分成7组,其中部分来源于同一产地的单株没有聚在同一组中,表明这些野核桃单株的遗传关系与其地理分布不完全一致.     

重楼属植物的细胞地理学研究

重楼属Paris有19种,分布于欧亚大陆。根据对本属所有种的染色体研究,重楼属染色体基数为5,核型的基本结构有两种形式：热带核型K2n＝2x=10=6m十4t和温带核型K2n=2x=10＝6m+4st或 6m+2st十2t。 热带核型的种(13种)分布在亚洲大陆的热带和亚热带;温带核型的种(6种)则出现在欧亚大陆的温带地域。重楼属的多倍体种的核型属温带核型,为本属的边陲种。四倍体种四叶重楼Paris quadrifolia分布在本属分布区的西端(欧洲);日本重楼P.japonica是八倍体种,局限在属分布区的东端(日本)。全部热带核型的种都是二倍体种。其中海南重楼P.dunniana等较原始种类都集中在华南和中南半岛北部。作者认为,亚洲大陆北纬18°至北回归线的热带地域是重楼属的起源地,云贵高原至邛崃山地域拥有14种重楼和9种核型结构式(全属有13种核型结构式),是重楼属的多样化中心,即现代分布中心。     

重楼属植物DNA提取的方法研究

为了获得重楼属植物高质量的DNA,以研磨、冻融和细胞溶胀破膜的原理设计了一种DNA提取的方法并与CTAB法和高盐法比较。结果显示该方法提取的重楼属植物DNA纯度（A260/A280=1.792-1.852;A260/A230=2.052-2.267）,产率（6.12-12.84mg/g）较其他两种方法高,降解少,节省药品。所提出的DNA能用于RAPD分析和ITS测序。     

四川重楼属植物2新记录变种

报道了四川重楼属植物2新分布变种,分别是宽瓣球药隔重楼(Paris fargesii var. latipetala H. Li et V. G. Soukup)和红果五指莲(Paris axialis H. Li var. rubra H. H. Zhou, K. Y. Wu et R. Tao)。其中红果五指莲为贵州特有类群,且为孤点分布。四川新分布的发现对于重楼属植物的系统分类和迁徙演化研究具有重要意义。     

大萼球药隔重楼,湖南重楼属(黑药花科)一新变种北大核心CSCD

报道了湖南重楼属(Paris L.)一新变种:大萼球药隔重楼(Paris fargesii Franch.var.macrosepala H.X.Yin&W.X.Rao&L.Zhao),其与原变种球药隔重楼(P.fargesii Franch.var.fargesii)区别在于外轮花被片极为宽大,长6.5~11.0 cm,宽2.5~4.0 cm,叶-萼长度比常小于2.0(平均1.91),叶-萼宽度比普遍小于3.0(平均2.86),内轮花被片较短,2.0~5.3 cm,常平展于外轮花被片之上,药隔凸出部分呈扁平状,具明显裂痕,顶面观呈蝶形或双肾形。     

SSRs transferability and genetic diversity of Tunisian Festuca arundinacea and Lolium perenne

SSR primers specific to Lolium perenne generated a total of 96 alleles and 124 genotypes within Festuca arundinacea and Lolium perenne accessions. Their highly transferability (100 %) across genera was evidenced. Six alleles specific to loci H01F02, H02C11 and K01A03 and only 5/96 common alleles between both species (60, 140, 144, 190 and 192) expressed the differentiation between species. Besides, based on the Wrights fixation indices, the genetic variation within each species was attributable to differences within populations with a significant deficiency of heterozygous. The unweighted pair group method with arithmetic averaging dendrogram based on the Nei’s distances and the principal coordinate analysis based on Jaccard coefficient similarity distinguished each genus independently of the geographical origin. However, typically continuous genetic diversity and a low level of gene flow (N_m: 0.29–2.47) expressed the relatively closely relationships of both genera and suggest a possible hybridization in nature.     

A genetic map of Xenopus tropicalis

We present a genetic map for Xenopus tropicalis, consisting of 2886 Simple Sequence Length Polymorphism (SSLP) markers. Using a bioinformatics-based strategy, we identified unique SSLPs within the X. tropicalis genome. Scaffolds from X. tropicalis genome assembly 2.0 (JGI) were scanned for Simple Sequence Repeats (SSRs); unique SSRs were then tested for amplification and polymorphisms using DNA from inbred Nigerian and Ivory Coast individuals. Thus identified, the SSLPs were genotyped against a mapping cross panel of DNA samples from 190 F2 individuals. Nearly 4000 SSLPs were genotyped, yielding a 2886-marker genetic map consisting of 10 major linkage groups between 73 and 132 cM in length, and 4 smaller linkage groups between 7 and 40 cM. The total effective size of the map is 1658 cM, and the average intermarker distance for each linkage group ranged from 0.27 to 0.75 cM. Fluorescence In Situ Hybridization (FISH) was carried out using probes for genes located on mapped scaffolds to assign linkage groups to chromosomes. Comparisons of this map with the X. tropicalis genome Assembly 4.1 (JGI) indicate that the map provides representation of a minimum of 66% of the X. tropicalis genome, incorporating 758 of the approximately 1300 scaffolds over 100,000 bp. The genetic map and SSLP marker database constitute an essential resource for genetic and genomic analyses in X. tropicalis.     

Molecular and morphological characterization of Leveillula (Ascomycota: Erysiphales) on monocotyledonous plants

Leveillula on monocotyledonous plants have been recorded as L. taurica by several authors, whereas the fungus on Allium has been described as an independent species, namely L. allii, by some authors. We sequenced ca 600 bp of the rDNA ITS region for two Leveillula specimens from Allium and Polianthes (both from monocotyledons) and compared them with several already published sequences from Leveillula isolates from dicotyledons. Pair-wise percentages of sequence divergences were calculated for all Leveillula isolates. The ITS sequence of the Polianthes isolate was identical to L. taurica on Helianthus and Vicia. The sequence of the Allium isolate was 99.5 % identical to L. taurica on Euphorbia, Haplophylum, Peganum, etc. These results suggest close relationships between monocot and dicot pathogenic Leveillula species. The identity between two monocot isolates was 98.4 %. Phylogenetic analysis revealed that the two monocot isolates do not group into a clade together. This result suggests that Leveillula acquired parasitism to monocots at least twice independently.     

内蒙古荒漠草原植物遗传多样性对模拟增温处理的响应

为探究全球变暖对温带荒漠草原地上种群的遗传影响,对已经接受模拟增温处理6年的短花针茅草原4种不同生活型植物,即半灌木、多年生禾草、多年生杂类草和一年生植物,应用AFLP分子标记方法研究了其遗传多样性和遗传结构。结果显示,对照处理与增温处理下的木地肤、短花针茅、细叶葱、猪毛菜4种植物的多态位点百分率(PPB)分别为11.32%,11.32%;40.83%,39.91%;14.29%,13.10%;19.85%,19.12%。Nei's基因多样性指数(He)分别为0.0274,0.0259;0.0812,0.0899;0.0131,0.0084;0.0506,0.0456。Shannon's信息指数值(I)分别为0.0447,0.0430;0.1354,0.1466;0.0267,0.0182;0.0811,0.0733。分子方差分析(AMOVA)显示4种植物的变异主要来源于实验处理内部,木地肤为85.03%,短花针茅为66.35%,细叶葱为70.00%,猪毛菜为66.52%;增温处理间的变异分别占-2.81%,-5.47%,-3.60%,2.53%(P0.05)。4种植物增温处理与变异程度之间在统计学上并无相关性。研究表明虽然短时间的模拟增温并不足以使4种生活型植物种群遗传多样性和遗传结构发生显著变化,但相对于3种多年生植物,一年生植物猪毛菜更容易受到增温影响。多年生和一年生植物对增温具有不同的遗传响应。     

65份野生油茶种质遗传多样性的ISSR和RAPD标记分析

利用ISSR和RAPD标记,对名邛台地野生油茶种质进行遗传多样性分析。从60条简单重复序列引物中筛选出16条引物,在65份样品中共扩增出213条带,其中多态位点为203个,多态位点百分率为95.31%;从30条寡居核苷酸引物中筛选出8条引物,共扩增出105条带,其中多态性位点94个,多态位点百分率为89.52%。结果表明:名邛台地野生油茶种质具有较丰富的遗传多样性,ISSR和RAPD标记可以应用于油茶种质遗传多样性分析。     

Colonization of cucumber plants by the biocontrol fungus Clonostachys rosea f. catenulata

Clonostachys rosea f. catenulata (Gliocladium catenulatum) strain J1446 (formulated as Prestop WP) suppressed Fusarium root and stem rot caused by Fusarium oxysporum f. sp. radicis-cucumerinum (Forc) on cucumber plants grown hydroponically in rockwool medium. Sixty days following application at seeding, the biocontrol agent had proliferated through the rockwool blocks and was present on cucumber roots and the crown region of the stem at populations >1 × 10⁵ CFU/g fresh weight. Scanning electron micrographs showed that C. rosea had rapidly colonized the root surface and was associated with root hairs and epidermal cell junctions. Following transformation of the fungus with Agrobacterium tumefaciens strain AGL-1 containing the hygromycin resistance (hph) and β-glucuronidase (uidA) genes, blue-stained mycelia could be seen growing on the surface and within epidermal and cortical cells of roots, stems and shoots 3 weeks after treatment. Quantification of GUS activity by fluorometric assays showed that fungal biomass was highest in the roots and crown area, while the extent of colonization of upper stems and true leaves was variable. Higher population levels resulted following application to rockwool blocks compared to seed treatment. Application of C. rosea preceding inoculation with Forc significantly reduced pathogen populations on roots compared to plants inoculated with Forc alone. Colonization of infection sites in the root zone reduced pathogen development and disease incidence. Densities of the biocontrol agent appeared to increase in the presence of the pathogen.     

睡莲属植物花粉形态研究

为明确睡莲属植物花粉形态特征,研究利用扫描电镜对18种或品种睡莲属植物的花粉形态特征进行观察,并对花粉形态及其种间亲缘关系进行分析,同时利用离体萌发法对睡莲品种‘彼得’的花粉活力进行测定,为睡莲杂交育种亲本的选择提供依据。结果表明:(1)18种或品种睡莲属植物的花粉均为单粒花粉,形态均为近球体或扁球体,其中巨花睡莲花粉粒最大,体积指数为30.3;埃及白睡莲花粉粒最小,体积指数为19.2。(2)花粉外壁纹饰类型繁多,包括网纹状、小颗粒状、瘤状、小柱状、长条状、微波纹起伏状。(3)根据聚类分析可将18种或品种睡莲属植物分为4个类群,其中Nymphaea亚属与Brachyceras亚属间亲缘关系最近。(4)‘彼得’的花粉离体萌发率高,可达95%以上。研究认为,睡莲属植物的花粉形态特征,特别是花粉萌发沟类型、外壁纹饰等特征可作为睡莲属植物种间分类、亚属间以及种间亲缘关系、系统进化规律的关键证据。