杉科植物的系统发育分析

本文以形态学为依据,参考其他学科的研究成果,用分支分类方法并结合表征分类方法探讨了杉科植物的系统演化关系,提出了新的分类系统。在分支分类中,金松科被选作外类群。主要根据外类群比较原则、化石原则和一般的演化规律,确定了性状的祖征和衍征,采用最大同步法、综合分析法、演化极端结合法及最小平行进化法共四种方法进行分支分析,选择最简约的分支图作为本文讨论基础。在表征分类中,选取59个性状,利用距离系数和类平均法,对金松属和杉科各属进行了聚类运算,得出表征图。综合两种分析结果,主要结论如下:(1)属间关系:柳杉属是现存杉科植物中最原始的类群。水松属和落羽杉属关系密切,二者与柳杉属近缘。巨杉属和北美红杉属关系密切,是中级进化水平的类群。水杉属与巨杉属和北美红杉属的亲缘关系相对较近。杉木属、密叶杉属和台湾杉属关系密切,是杉科植物中的高级进化类群,其中又以台湾杉属演化水平最高。(2)系统排列:支持金松科的成立,将杉科分成5族,即柳杉族(仅含柳杉属)、落羽杉族(含水松属、落羽杉属)、北美红杉族(含巨杉属、北美红杉属)、水杉族(仅含水杉属)和杉木族(含杉木属、密叶杉属及台湾杉属)。     

分支系统学当前的理论和方法概述及华东地区山胡椒属十二个种的分支系统学研究

本文概述了当前分支系统学研究中涉及的主要理论和方法,包括性状的选取、性状状态和极性的确定、数据矩阵的分析计算、结果分支图的处理、分支图可靠性的评价及分支图的应用。本文同时以华东地区樟科山胡椒属Linderal2个种的分支系统学研究为例,讨论了用形态性状进行分支系统学研究中可能遇到的问题,也揭示了一些分支系统学与传统的系统学在应用性状推导进化关系上的不同点。对这12个种的分支系统学研究得出了一些不同于传统系统学方法所推测的山胡椒属内的系统发育关系,如分支系统学研究显示山胡椒组和球果组很近缘。在严格一致性分支图上,杯托组的黑壳楠和江浙山胡椒分别位于最原始和最进化的分支,表明这个组是复系类群。分支图也显示山胡椒组可能是复系类群。     

trnK基因5′端内含子区序列在榆科(广义)系统发育研究中的应用

本文测定了广义榆科 Ulmaceae s．l．及其近缘类群的trn K基因5′端内含子区序列。在尝试利用该内含子区进行榆科系统发育研究的同时,探讨了其在植物系统学研究中的应用前景。利用PAUP软件进行的系统发育分析仅得到1棵最简约树。该简约树的树长为665步,其一致性指数(CI)和保持性指数(RI)分别为0.7714和0.7965。分析结果表明：广义榆科为多系群;狭义榆科Ulmaceae s．str．为荨麻目rticales其他类群的姊妹群;大麻科Cannabacea嵌在朴科Celtidacea中,即朴科为一并系群;系统位置有争议的2个属——白颜树属Gironniera和糙叶树属 Aphananthe与朴科类群聚为一支。本研究还表明trnK基因5′端内含子区序列分析在植物较低分类等级(如近缘属间,属下种间)的系统发育研究中具有很好的应用前景。     

药材牡丹皮的原植物——芍药属一新变种

药用牡丹 新变种 Paeonia ostii T.Hong etJ.X.Zhang Var.lishizhenii B.A.Shen,var.nov. A var.ostii differt foliis saepe imparipinnatis vel bipinnatis,foliolis ad 14 cm longis,ad 8cm latis,petiolulis ad35mm longis,floribus majoribus 14～20cm diam,petalis7～10cmlongis,folliculis 5～8,3.5～4.5 cm longis,seminibus 0.9～1.2 cm longis.     

中国玄参属一新种

太行玄参 新种 图1 Scrophularia taihangshanensis C. S. Zhu et H. W. Yang,sp. nov. (Sect. Scrophularia) Species S. macrocarpae Tsoong affinis, a qua differt panicula e racemis 8～15 cmlongis composita, rhachidi et ramulis paniculae tenuibus flexuosis, calyce 2.5～3 mm longo,lobis corollae oblongis vel obovato-oblongis, anthera staminodii oblonga, stylo ovario 4～5 plo     

凤仙花属花粉形态及其分类学意义

本文作者首次观察了峨眉山凤仙花属Impatiens 13个野生种的花粉形态,发现3沟和4沟类型 花粉均出现在这一地区。其中3沟花粉与同科另一属水角属Hydrocera的花粉十分相似。同时注意到 花粉形态与其花的形态在某些方面具相关性,结合地理分布和生长习性等特性,得出以下结论：1．凤仙 花属3沟型花粉所指示的植物类群为一自然类群,并与水角属具有较密切的亲缘关系;2．凤仙花属4沟型花粉常具种水平上的差异,对属内类群划分具有系统学意义。     

中国蔷薇属一新种

Anhui(安徽):Chuxian(滁县),Langyashan(琅琊山),Nantianmen(南天门),alt.150m,margin of forest,1991-05-25,J.Z.Shao(邵建章)90801(type,ANUB);the same lo-cality,1990-05-26,J.Z.Shao,90581. 灌木,高2～3m,小枝圆柱形,有直或稍弯的皮刺。奇数羽状复叶,小叶(7～)9枚,连叶柄长5～9cm,小叶片长椭圆形,最上1对小叶最小,长1.3～2cm,宽4～7mm,顶小叶     

松科的核型和系统发育研究

松科通常主要依据长、短枝及叶等的形态特征分成冷杉亚科、落叶松亚科和松亚科。该科各属的核型可以划分成5个类型：(1)松型(24(22)m+0(2)sm);(2)冷杉型((22～14)m十(2～l0)sm(st));(3)落叶松型(12m+12sm(st));(4)花旗松型(10m+12sm+4t);(5)金钱松型(4sm+40t(4SC))。本文根据核型资料的比较分析,各属从原始到进化的顺序可能是：松属(松型核型)-银杉属、云杉属、铁杉属、(雪松属)、油杉属、冷杉属(冷杉型核型)→黄杉属、落叶松属(花旗松型核型和落叶松型核型)→金钱松属(金钱松型核型)。这个顺序和亲缘关系在以核型的平均臂比为纵坐标、染色体长度比为横坐标的坐标图上得到清楚反映(不包括金钱松属)。核型为K(2n)＝44＝4sm+40t(4SC)的单型属金钱松属不仅在染色体数目和核型上与其他各属差异明显,而且具有独特的习性和-系列形态学和解剖学的特征,如落叶乔木(仅同落叶松属),短枝之叶簇状密生而辐射平展呈圆盘状,叶枕在落叶后密集成环节状,雄球花多数簇生短枝顶端,种鳞卵状披针形,成熟时与基部贴生的苞鳞连同崩解的球果中轴一起脱落,叶中3个树脂道及其分布,维管束帽缺如以及传输组织铁杉型(仅同铁杉属)等。因此,本文将金钱松属提升为一个新亚科Pseudolaricoideae L.C．Li,并把原来的3个亚科降为相应的族而隶于松亚科。松科里唯一具K(2n)=24＝12m+12sm(st)核型的黄杉属和落叶松属组成落叶松族,而雪松属按其核型与冷杉族更相近而置于该族。本文根据核型资料建立的松科新系统也得到形态、解剖、植化、免疫、生化、胚胎及占植物等学科有关资料的支持。本文还讨论了前人的松科演化系统。     

淡水豚类分子系统发生的研究

测定了白暨豚和恒河豚细胞色素ｂ基因３０７ｂｐ的ＤＮＡ序列,并与其它鲸类的相应序列合并,分析了淡水豚类（恒河豚、印河豚、白暨豚、亚河豚和弗西豚）的系统学位置和系统发生。淡水豚类不同属间的序列差异已达到或超过了其它齿鲸类科间的差异水平,因此它们分别归属于不同的科,即恒河豚科、白暨豚科、亚河豚科和弗西豚科。系统发生分析支持淡水豚类和海豚类之间具有下述的关系：（恒河豚科（（白暨豚科（亚河豚科,弗西豚科））海豚总科））。即淡水豚的４个科中,恒河豚科是最早分化的一支,其次是白暨豚科,然后是亚河豚科和弗西豚科的分化。白暨豚科和亚河豚科＋弗西豚科组成海豚总科的姊妹群,并与海豚总科一同组成海豚下目。恒河豚与其它淡水豚类间无直接的亲缘关系。淡水豚类是并系的。把恒河豚类独立为恒河豚总科是合理的。初步认为有理由把白暨豚类也作为一个总科级的支系。恒河豚和印河豚间的序列差异极小,两者可能只是同一个种的２个亚种。     

MOLECULAR PHYLOGENY OF THE GREEN ALGAL ORDER PRASIOLALES (TREBOUXIOPHYCEAE,CHLOROPHYTA)1

The systematics of the Prasiolales was investigated by phylogenetic inference based on analyses of the rbcL and 18S rRNA genes for representatives of all four genera currently attributed to this order (Prasiococcus, Prasiola, Prasiolopsis, Rosenvingiella), including all type species. The rbcL gene had higher sequence divergence than the 18S rRNA gene and was more useful for phylogenetic inference at the ranks of genus and species. In the rbcL gene phylogeny, three main clades were observed, corresponding to Prasiola, Prasiolopsis, and Rosenvingiella. Prasiococcus was nested among species of Prasiola occurring in subaerial and supralittoral habitats. Trichophilus welckeri Weber Bosse, a subaerial alga occurring in the fur of sloths in Amazonia, was closely related to Prasiolopsis ramosa Vischer. The species of Prasiola were grouped into three well‐supported clades comprising (i) marine species, (ii) freshwater and terrestrial species with linear blades, and (iii) terrestrial species with rounded or fan‐shaped blades. Sequence divergence was unexpectedly low in the marine group, which included species with different morphologies. For the 18S rRNA gene, the phylogenetic analyses produced several clades observed for the rbcL gene sequence analysis, but, due to very little sequence variation, it showed considerably lower resolution for inference at the species and genus levels. Due to the low support of some internal branches, the results of the analyses did not allow an unambiguous clarification of the origin and the early evolution of the Prasiolales.     

分子伴娘60类群的系统发育学分析

有充分的证据支持线粒体和叶绿体起源的内共生假说,即:紫色细菌、α—类群的成员是线粒体的祖先,而蓝细菌的成员是叶绿体的祖先。这一证据来自分子伴娘60蛋白为基础的系统发育学分析,并且与16S rRNA序列为基础的分析结果是完全一致的。这一结果还说明,嗜碱芽胞杆菌C-125菌株在系统发育地位上更接近枯草芽孢杆菌。     

速足目主要类群系统发育的分子证据

文章基于速足目现生主要类群18S rDNA、28S rDNA和COI基因序列,采用贝叶斯法、邻接法和最大简约法,尝试构建速足目的分子系统树;结合形态特征和化石记录,主要对速足目各超科级分类阶元的系统发育关系进行探讨。结果表明,速足目现生超科Bairdiacea、Darwinulacea、Cypridacea和Cytheracea均为单系群,支持形态学上关于上述4个超科的的界定;3种基因均支持形态学上Darwinulacea和Cypridacea具有较近的亲缘关系的观点。18S rDNA序列分析在较显著水平上支持Darwinulacea和Bairdiacea为姐妹群,Darwinulacea可能从Bairdia-cea中的一支演化而来;Bairdiacea和Darwinulacea组成的分支是Cypridacea的姐妹群,支持将三者合并为Bairdio-copina亚目的观点;Cytheracea是Cypridacea(Darwinulacea Bairdiacea)的姐妹群,可提升为Cytheracopina亚目。     

A MOLECULAR PHYLOGENY OF THE HETEROKONT ALGAE BASED ON ANALYSES OF CHLOROPLAST-ENCODED rbcL SEQUENCE DATA1

Nearly complete ribulose-1,5-bisphosphate carboxylase/ oxygenase (rbcL)sequences from 27 taxa of heterokont algae were determined and combined with rbcL sequences obtained from GenBank for four other heterokont algae and three red algae. The phylogeny of the morphologically diverse haterokont algae was inferred from an unambiguously aligned data matrix using the red algae as the root, Significantly higher levels of mutational saturation in third codon positions were found when plotting the pair-wise substitutions with and without corrections for multiple substitutions at the same site for first and second codon positions only and for third positions only. In light of this observation, third codon positions were excluded from phylogenetic analyses. Both weighted-parsimony and maximum-likelihood analyses supported with high bootstrap values the monophyly of the nine currently recognized classes of heterokont algae. The Eustigmatophyceae were the most basal group, and the Dictyochophyceae branched off as the second most basal group. The branching pattern for the other classes was well supported in terms of bootstrap values in the weightedparsimony analysis but was weakly supported in the maximum-likelihood analysis (<50%). In the parsimony analysis, the diatoms formed a sister group to the branch containing the Chrysophyceae and Synurophyceae. This clade, charactetized by siliceous structures (frustules, cysts, scales), was the sister group to the Pelagophyceae/Sarcinochrysidales and Phaeo-/Xantho-/ Raphidophyceae clades. In the latter clade, the raphido-phytes were sister to the Phaeophyceae and Xanthophyceae. A relative rate test revealed that the rbcL gene in the Chrysophyceae and Synurophyceae has experienced a significantly different rate of substitutions compared to other classes of heterokont algae. The branch lengths in the maximum-likelihood reconstruction suggest that these two classes have evolved at an accelerated rate. Six major carotenoids were analyzed cladistically to study the usefulness of carotenoid pigmentation as a class-level character in the heterokont algae. In addition, each carotenoid was mapped onto both the rbcL tree and a consensus tree derived from nuclear-encoded small-subunit ribosomal DNA (SSU rDNA) sequences. Carotenoid pigmentation does not provide unambiguous phylogenetic information, whether analyzed cladistically by itself or when mapped onto phylogenetic trees based upon molecular sequence data.     

中国松科植物的分布型和区系分析

简介松科研究的新进展,根据新近资料划分中国松科植物10属95种的分布型和进行区系分析,结果是北温带分布4属,东亚-北美间断分布2属,中国特有3属和越南-华南分布1属。25个种分布型分属于欧亚温带、东亚和亚洲热带3个植物区域。比较详细分析其4点主要特征;分布的区域差异和不平衡,高的特有性,间断分布和替代分布等。     

MOLECULAR PHYLOGENY OF THE HAPTOPHYTA BASED ON THE rbcL GENE AND SEQUENCE VARIATION IN THE SPACER REGION OF THE RUBISCO OPERON

A phylogeny of 21 haptophyte algae was inferred by maximum parsimony, neighbor-joining, and maximum likelihood analyses of sequences of the plastid-encoded gene, rbcL. Sequence variation in the spacer region of the RUBISCO operon was also investigated. In all the rbcL trees constructed, the haptophytes form two distinct clades: one includes the Pavlovales and the other includes the Prymnesiales, Coccosphaerales, and Isochrysidales (all sensu Parke and Green 1976 . This relationship coincides with the recent taxonomic treatment splitting the division into two subclasses, the Prymnesidae and Pavlovidae ( Cavalier-Smith 1989 ) or the Prymnesiophycidae and the Pavlovophycidae using botanical suffixes ( Jordan and Green 1994 ), or into two classes, the Patelliferea and the Pavlovea ( Cavalier-Smith 1993 ). In the Prymnesiophycidae, all the coccolithophorids examined are placed in a single clade, which suggests a single origin of the coccolithophorids and the ability of coccolith formation in the haptophytes. The genus Chrysochromulina is polyphyletic. Species of Chrysochromulina with a very long haptonema and a compressed cell body (typical of species including the type C. parva Lackey) form a clade, including Imantonia, that is often classified in the Isochrysidales in the neighbor-joining tree, whereas some species possessing a nontypical cell body and cell covering form a clade with Prymnesium and Platychrysis in all trees. It is suggested that loss of the haptonema in Imantonia and the reduction in Prymnesium and Platychrysis occurred secondarily and independently in two different lineages. Within the coccolithophorids, four clades are recognized: Pleurochrysis, Calyptrosphaera-Cruciplacolithus-Calcidiscus-Umbilicosphaera, Helicosphaera, and Emiliania-Gephyrocapsa. A non-coccolith-bearing haptophyte, Isochrysis, is an ingroup of the Emiliania-Gephyrocapsa clade, suggesting its secondary loss of the ability to form a coccolith. Sequence comparison of the spacer region of RUBISCO operon supports most results obtained in the analysis of rbcL sequences. Monophyly of the Prymnesiales sensu Parke and Green is still unclear because of low (<50%) bootstrap support for this group.     

MOLECULAR PHYLOGENY OF DISCOSPORANGIUM MESARTHROCARPUM (PHAEOPHYCEAE) WITH A REINSTATEMENT OF THE ORDER DISCOSPORANGIALES1

A molecular phylogenetic analysis of the little‐studied filamentous brown alga Discosporangium mesarthrocarpum (Meneghini) Hauck using rbcL and partial 18S rDNA sequences revealed that the species forms a monophyletic clade with Choristocarpus tenellus (Kütz.) Zanardini that is sister to all other brown algae. Although D. mesarthrocarpum has unique disk‐shaped plurilocular reproductive organs, D. mesarthrocarpum and C. tenellus share the following basic morphological features, which are considered to be plesiomorphic characters in the brown algae: (1) apical (and diffuse) growth; (2) uniseriate, subdichotomously branched filaments; (3) multiple chloroplasts per cell without pyrenoids; and (4) lack of heterotrichy and of phaeophycean hairs. The rbcL DNA sequence of an Australian D. mesarthrocarpum specimen showed considerable deviation from Mediterranean and Macaronesian specimens. Therefore, the presence of a second species in the genus is suggested; however, the taxonomic treatment of this putative species is not pursued in the present report. Regarding the higher‐ranking systematic position of D. mesarthrocarpum, reinstatement of Discosporangiaceae and Discosporangiales is proposed, and the inclusion of Choristocarpaceae in the order is also suggested. Under short‐day and long‐day culture conditions at 15°C–25°C, Mediterranean D. mesarthrocarpum exhibited a direct type of life history, with a succession of uniseriate filamentous thalli bearing characteristic disk‐shaped plurilocular zoidangia, but thalli did not survive at 10°C and below.     

木霉分子生物学研究进展

木霉Trichoderma spp.是普遍存在并具有重要经济意义的一类真菌。本文试从木霉大分子;基因克隆;转化系统;外源基因表达;在工农业生产中的应用等方面对木霉分子生物学研究进展进行综述。