中国薯蓣属植物叶表皮微形态特征及其分类学意义

利用扫描电子显微镜(SEM)对中国薯蓣科薯蓣属7组31种1亚种2变种植物的叶表皮细胞、叶表皮毛、气孔器类型、气孔大小、气孔纹饰等叶表皮微形态特征进行了观察和比较研究,为薯蓣属内种间的分类界定及系统发育研究提供证据。结果表明:中国薯蓣属各组之间在叶表皮毛、叶表皮细胞和气孔等微形态特征存在较大的差异,但也呈现出一定的组间特异性规律,如:四至六边形的叶表皮细胞、气孔周围平直的垂周壁式样为根茎组植物所特有;丁字型毛组叶脉和叶肉细胞上覆盖大量特有的2叉T型表皮毛;复叶组的叶脉和叶肉细胞具相当密集的表皮毛;基生翅组和周生翅组的气孔器类型衍生出了三胞型;气孔旋转方向在各组中明显分化,在丁字型毛组、白薯莨组和周生翅组(多毛叶薯蓣除外)中为左旋,而顶生翅组、基生翅组和复叶组表现为右旋。研究表明,叶表皮微形态特征在薯蓣属植物中是较为稳定的演化特征,可以作为中国薯蓣属分类与鉴定的依据;据此推断薯蓣属中顶生翅组和周生翅组较为进化,根茎组是薯蓣属的分化中心;对薯蓣属中存在争议的种:盾叶薯蓣和小花盾叶薯蓣、穿龙薯蓣和柴黄姜、马肠薯蓣、多毛叶薯蓣以及白薯莨等进行了分类界定。     

五味子属植物种子形态特征及其分类学意义

在扫描电镜下观察了70多份五味子属种子样品,并拍摄了照片,其中34幅展示在文中。选取代表27个分类群,34个居群的36份种子样品,每份样品20粒,测量长、宽、厚,取平均值。采用“相对体积”这一新概念作为种子形态比较的一项指征。同时对种子整体照片所呈现的表面纹饰进行了分析归纳,将其分为4个类型：（1）平滑或基本平滑,（2）有明显的皱纹,或有或疏或密的疣状突起,（3）有密集而显著的乳头状突起,（4）密被不规则的、有结节的绳索状突起,突起物曲折蜿蜒,酷似哺乳动物的大脑。综合种子的大小、颜色、表面整体纹饰以及雄蕊群特征等分析的结果表明,少蕊组sect．Maximowiczia、五味子组sect．Schisandra和球蕊组sect．Sphaerostema的种子形态分别与其雄蕊群特征具有高度的相关性;而多蕊组sect．Pleiostema的情况稍微复杂一点,但种子形态与与其雄蕊群特征之间仍然有部分相关性。本文以种子的整体形态为基础讨论五味子属种子表面形态在该属分类上的意义。研究种子整体形态得到的证据与研究种子表面微形态得到的证据一致,不支持林祁（2000）和Saunders（2000）对五味子属的分类修订,也不支持刘玉壶（1996）将球蕊组sect．Sphaerostema划分成两个亚属的修订。     

五味子属种子形态及其分类学意义

用光学显微镜及扫描电镜对五味子属（Schisandra)10种96号样品的种子宏观形态和种皮的微观形态特征进行观察,首次对该属的种皮微观形态特征进行系统报道,并编排有分种检索表。研究结果表明：该属的种子宏观形态呈现平滑、细皱纹或瘤状突起,并认为五味子属种子形态可有从平滑到有细皱纹再到有瘤状突起的演化趋势;该属种皮表面微观形态可分为疣状突起型和网纹型。结合其它性状,本文认为网纹型所代表的两种植物应与本属中其它植物建立并列的分类单元。五味子属植物在种子形态特征上存在一定的差异,可为属以下、种以上的分类提供依据,并为探讨该属的系统演化提供有价值的参考资料。     

杜鹃花属植物花粉形态及其分类学意义

利用扫描电子显微镜对5个亚属20种杜鹃花属植物的花粉形态进行了观察和比较研究,其中大部分(16种)为首次报道。杜鹃花属花粉均为四合花粉,呈正四面体排列。四合体为圆角三角形,连接紧密。单粒花粉为球形或近球形,具三沟孔。在扫描电镜下,除了杜鹃亚属的百合杜鹃、羊踯躅亚属的羊踯躅以及马银花亚属的马银花组具有明显的纹饰特征之外,其它类群的形态特征相互重叠,不足以作为现有亚属的分类依据。花粉粒具不同的外壁纹饰,可为分类研究提供孢粉学方面的证据,但应慎重应用花粉形态对杜鹃花属植物特定种进行分类鉴定。     

山茶属的花粉形态及其分类学意义

本文对山茶属(Camellia L.)18个组27个代表种的花粉进行了光学显微镜、扫描电镜和大部分进行了透射电镜的观察,并对花粉大小、形状、外壁纹饰和超微结构等作了综合的比较。结果表明,其形状和大小差异不很明显。花粉壁的层次、厚度和不同层次的比例,如复盖层与柱状层以及外壁外层与外壁内层的比例等也没有显著的差异。但花粉壁的纹饰特征在扫描电镜下显示出较大的差异,具有较重要的分类学价值。根据其纹饰特征,可以把山茶属花粉大致区分为六个类型:皱疣状纹饰;粗瘤状纹饰;颗粒状至皱-颗粒状纹饰;穴-网状纹饰;皱沟状纹饰及皱波-念珠状纹饰。孢粉学上区分的类型不完全与各个学者从植物形态上划分的组相一致。其中管蕊茶 Camellia lanceolata的纹饰非常特殊(粗瘤状),其外壁表面很象牛心果(Annona reticulata)的外形特征,为其重新分类提供孢粉学依据。     

中国绣线菊属植物种子形态及其分类学意义

利用光学显微镜和扫描电镜对中国25种4变种绣线菊属(Spiraea L.)植物的种子形态特征进行了研究。结果显示,绣线菊属植物种子外观上呈窄线形至椭圆形,表面有光泽和条纹,种子颜色为红棕色至深褐色;种皮纹饰可分为网纹、复网纹、负网纹和链状网纹4种类型。种子按长宽比的划分方法在一定程度上支持该属传统的组下系的划分;种皮纹饰在种间具有明显的差异,可作为中国绣线菊属植物种的分类依据。本研究为绣线菊属的分类及系统学研究提供了种子形态及种皮微观形态方面的新资料,对进一步完善该属属下分类具有借鉴意义。     

星果泻属的果实形态特征及其分类学意义

利用解剖镜和扫描电子显微镜详细观察了泽泻科星果泻属全部5种植物的果实形态和微形态特征,发现该属植物的果实：常为蓇葖果具2～6枚种子;稀瘦果具1枚种子,扁压,不规则长方形,顶端一侧延伸成尾状长喙;或果实三角形,喙不明显。果皮上有角质层覆盖,角质层的纹饰为条状或细条状,上面密被碎屑状、颗粒状或稀疏的颗粒状蜡质附属物。这些特征可作为属下分类的依据。本文在前人研究的基础上对该属的分类进行了讨论并写出新的分种检索表。笔者认为将星果泻和星状星果泻各自作为独立的种可能更为合理;加州星果泻仍应放在星果泻属内,而星果泻则可能是加州星果泻与该属其它种联系的一个中间过渡类型;多籽星果泻不宜与星果泻全并,仍应保留为一独立的种。笔者还首次发现该属植物的果皮上分布有气孔。     

杜鹃花属映山红亚属植物叶表皮显微形态特征及其分类学意义

为澄清映山红亚属(Rhododendron subg. Tsutsusi)内的系统关系问题,该研究选择杜鹃花属映山红亚属37种植物作为对象,其中29种为首次报道,通过扫描电镜观察其叶表皮显微特征。结果表明:(1)气孔器均为无规则型且均在远轴面。(2)根据叶片微形态特征将映山红亚属的种类分为杜鹃型(R. simisii-type)、岭南杜鹃型(R. mariae-type)、皋月杜鹃型(R. indicum-type)、崖壁杜鹃型(R. saxatile-type)及丁香杜鹃型(R. farrerae-type)5种类型。(3)杜鹃型植物的气孔器周边无或具间断的条形突起。(4)岭南杜鹃型植物的气孔器周围有多层条形突起环绕,保卫细胞两极不具T型加厚。(5)皋月杜鹃型植物的叶表皮保卫细胞两极具有T型加厚,与叶状苞亚属(Subg. Therorhodion)叶状苞杜鹃(R. redowskianum)的气孔器特征相似,推测其与叶状苞亚属具有一定的亲缘关系。(6)崖壁杜鹃型植物的叶表皮毛单一,多呈卷曲状,与其他类型有所不同且未见腺体。(7)丁香杜鹃型植物的叶表皮仅有腺体。(8)依据叶表皮微形态特征讨论了一些近缘种类的关系,如倾向于将背绒杜鹃(R. hypoblematosum)和千针叶杜鹃(R. polyraphidoideum)处理为独立的种,支持保留紫薇春(R. naamkwanense var. cryptonerve)作为南昆杜鹃(R. naamkwanense)的变种地位,不支持将腺花杜鹃(R. adenanthum)并入细瘦杜鹃(R. tenue)作异名处理等。该研究结果表明叶表皮显微特征在映山红亚属内物种划分上具有重要价值。     

国产委陵菜属植物果实形态及其分类学意义

对国产委陵菜属Ｐｏｔｅｎｔｉｌｌａ３２种及变种植物的果实形态在实体解剖镜和扫描电镜下进行了研究。结果表明：在扫描电镜下,本属植物果实表面纹饰有５种不同的类型,即网纹型,疣状突起型,波纹型,帽状突起型和不规则型;果实形态特征,特别是电镜下的果皮表面纹饰对本属植物的分类具有较重要价值;根据果实形态,支持将金露梅、银露梅、小叶金露梅做为独立的种。     

鹅观草属部分种的叶表皮微形态特征及其分类学意义

在过去叶表皮实验的基础上,本从鹅观草属不同组、系中新增解剖了１６个有代表性的种。根据这些种叶片反映的表皮微形态特征,进一步证实了鹅观草属共族分属以及属下类群划分的正确性,揭示了属中各主要类群的演化水平和系统发育关系。研究结果最后表明：鹅观草属的半颖组最原始,在系统发育中它可能既派生了较进化的小颖组和大颖组,又派生了最进化的长颖组;在大颖组中,齿草系较原始,纤毛草系较进化,宽叶草系最进化,纤毛草系     

Seed morphology in Moehringia L. and its taxonomic significance in comparative studies within the Caryophyllaceae

Seeds of 30 species of Moehringia and 12 representatives of the Caryophyllaceae were examined with the Scanning Electron Microscope. High diversity was found in seed coat micromorphology, and a number of novel morphological features have been observed. Comparison with other representatives of the Caryophyllaceae has provided new insight into the potential taxonomic value of discrete morphological characters. Though many characters appear informative within Moehringia, they are affected by a high level of homoplasy when considered in a wider phylogenetic context. Smooth seed is the common condition in Moehringia, except for Eastern Balkan and Iberian species that maintain a secondary ornamentation of the testa cells resembling the plesiomorphic Caryophyllaceae-type. Five types of strophioles were recognized, in accordance with previous literature. Among these, the strophiole of the Iberian species appears very distinctive and a proper strophiole could not be verified in M. glochidisperma and M. fontqueri.     

湖北薯蓣属植物资源

湖北薯蓣属植物有１４种,３变种,１亚种,属于块茎组的有７种,２变种,均含多量淀粉,不含薯蓣皂甙元。属于根状茎组的有７种,１变种,１亚种,除含淀粉外,都含有一定量的薯蓣皂甙元,其中盾叶薯蓣的含量最高,平均含量为３％,且其含量随生长环境而变化,由南向北呈递增趋势,盾叶薯蓣在湖北主要分布在宜昌地区,襄樊,神农架和郧阳地区,蕴藏量约３．５万吨。     

中国伞形科前胡属果实表面微形态特征及分类学意义

采用扫描电镜方法对中国伞形科(Apiaceae)前胡属(Peucedanum L.) 22种2变种的果实表面微形态特征进行了观察和描述.结果显示:供试种类在果实棱槽细胞平滑度和细胞轮廓可见度、蜡质纹饰类型、细胞表面突起的有无及类型、表皮毛的有无及类型及其纹饰类型、表皮分泌物的有无及类型等方面有明显差异,具有丰富的种间多样性.根据这些特征可将供试种类分为4种类型.类型Ⅰ:棱槽细胞粗糙多毛—细胞轮廓不可见—簇状蜡质纹饰发达,包含滨海前胡(P.japonicum Thunb.)、天竺山前胡(P.ampliatum K.T.Fu)、华北前胡(P.harrysmithii Fedde ex Wolff)及其2变种、长前胡(P.turgeniifolium Wolff)、华山前胡(P.ledebourielloides K.T.Fu)和泰山前胡[P.wawrae (Wolff) Su ex Sheh];类型Ⅱ:棱槽细胞平滑无毛—细胞轮廓不可见或凹陷—条形蜡质纹饰发达或明显,包含芷叶前胡(P.angelicoides Wolff ex Kretschm.)、竹节前胡(P.dielsianum Fedde ex Wolff)、南川前胡[P.dissolutum (Diels)Wolff]、红前胡(P.rubricaule Shan et Sheh)、细裂前胡(P.macilentum Franch.)、前胡(P.praeruptorum Dunn)、华中前胡(P.medicum Dunn)、台湾前胡(P.formosanunt Hayata)、南岭前胡(P.longshengense Shum et Sheh)、会泽前胡(P.acaule Shah et Sheh)和马山前胡(P.mashanense Shan et Sheh);类型Ⅲ:棱槽细胞有稀疏毛—细胞轮廓[陷可见或不明显—蜡质纹饰几无,包含北京前胡(P.caespitosum Wolff)、草原前胡(P.stepposum Huang)、毛前胡(P.pubescens Hand.-Mazz.)和刺尖前胡(P.elegans Komarov);类型Ⅳ:棱槽细胞不平无毛—细胞轮廓呈近圆形凸起—蜡质纹饰为微波状长条形,仅包含石防风[P.terebinthaceum (Fisch.ex Trevir.)Fisch.ex Turcz.]1种.结合外部形态特征以及地理分布对各类型种类的分类关系进行了讨论,并对会泽前胡、马山前胡和石防风的特殊分类地位进行了分析,明确了果实表面微形态特征在前胡属中的分类学意义.     

中国薯蓣属植物中的甾体皂苷及甾体皂苷元

中国薯蓣属(Dioscorea L.)植物含有约21种甾体皂苷元,其中大部分种类含有3β-羟基皂苷元,少数种类含有3α-羟基皂苷元。从薯蓣属13种植物中共分离出59个甾体皂苷成分,按化学结构可将这些甾体皂苷分为4种类型。约有17种薯蓣属植物含有甾体皂苷元(主要为薯蓣皂苷元),均为根茎组(Sect.Stenophora)种类。在查阅大量资料的基础上,对各种类所含的甾体皂苷元和甾体皂苷成分及各成分的化学结构进行了归纳和综述。     

The flavonoids in Epimedium L. and their taxonomic significance

In this paper, the distribution and quantity of flavonol glycosides with isoprenyl in the eighth position (A kind) or without isoprenyl (B kind) in Epimedium were analyzed by HPLC. The following results of taxonomic significance were obtained: 1 )According to the chemical characteristics, Epimedium could be divided into three groups: A group, mainly with A kind of flavonol glycosides; B group, mainly with B kind of fiavonol glycosides; AB group, sharing the two kinds. Eight taxa (species or subspecies) in B group, which have many advanced charaetaristics, should represent a more advanced group of the genus. The species of AB group were relatively primitive in the genus. Hence the evolutionury trend from AB group to A group and then to B group was possible. This trend is basically correlated with that of morphological evolution. But the above groupings of A, B and AB do not accord with Stearn's taxonomic system and the results of pollen morphology and of chromosome C-bands. 2)E. alpinum, a species distributed in the Mediterranean area, contains a high quantity of A2 kind of compounds (those of A kind with 4'-OH), so it may be somewhat related to the primitive species in China. 3)The constituents of E. davidii and E. ecalcaratnm are almost identical, implying that the prescence or absence of the spur of the petal should be of unimportant systematic significance. 4)The chromngram of HPLC provided reliable evidence for determining the parental origin of the hybrid E. x fanjingshanense. The results of this work provided new evidence for establishing a more reasonable taxonomic system of Epimediurn, but the taxonomic research on Epimedium has a long way to go and more work must be done. Other chemical characteristics of Epimedium and its relationshipwith other groups in the Berberidaceae were also discussed. 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淫羊藿属植物中的黄酮类成分及其分类学意义

用HPLC法研究了具8位异戊烯基的黄酮醇甙类(A类)及一般结构的黄酮醇甙类(B类)在淫羊 藿属Epimedium L.中的存在和含量情况,得到一些具分类学意义的结论。1)依据化学成分可将 Epimedium 分为3群：A群,主要含A类成分;B群,主要含B类成分;AB群,两类化合物含量都高。B 群的8个类群(种或亚种)有多项演化程度较高的形态特征,它可能是Epimedium发展演化中较为进化 的一个分支群。—朋群的种类为本屑较原始的类群,因而在化学性状上有朋群→A群、AB群→B群的 演化趋势,与形态演化趋势基本相关。A、B、AB群的划分与现有分类系统不一致,也与花粉、染色体C 带的结果不很吻合。2)分布于地中海的E. alpinum因有较高含量的厶2类成分(A类中4'-OH的一类 化合物)而体现了与中国的原始类群的一些联系。3)E. davidii和E. ecalcaratum的化学成分几乎相 同,表明花瓣距的有无在Epimedium中的原始类群可能不具重要的分类价值。4)HPLC图谱为E.Х fanjingshanense这一杂交种的亲本来源提供了可靠的证据。本研究结果为建立一个合理的Epimedium的分类系统提供了新的依据。     

国产省藤属植物的叶表皮形态学

对国产省藤属（Calamus L．）植物17种2变种的叶表皮进行光学显微镜观察,除单叶省藤（C.simplicifolius）、短叶省藤（C.egregiw）和白藤（C.tetradactylus）外,其它种均为首次报道。省藤属植物的叶表皮形态较为一致,气孔器为轮列4细胞型（tetracytic,或称四轮列型）,即有4个副卫细胞,其中2个为侧副卫细胞,2个为端副卫细胞;表皮细胞为长方形,纵向排列。表皮毛有3种类型：多细胞排成单列的单毛（人喙省藤C．macrorrhynchus）、多细胞排成2-3列的单毛（毛鳞省藤ethysanolepis等）、多细胞分枝毛（白藤等）。表皮细胞的长度和宽度特征、细胞壁的厚薄及波纹的深浅和形状、端副卫细胞的长短等细微特征在种问存在差异,可以区分种类。叶表皮结构还反映了种问的亲缘关系。因此,叶表皮特征对于省藤属种类的划分和亲缘关系的确定有较大的分类学意义。     

Morphological and genetic diversity within Pilosella hoppeana aggr. (Asteraceae) in Italy and taxonomic implications

Morphological variation, ploidy level and genetic diversity have been studied on 10 populations of the Pilosella hoppeana aggr. from the Alps, Abruzzo, Calabria and Sicily. Chromosome counts showed that the plants from Abruzzo and those from Sicily are tetraploid (2n = 36); they are assigned to P. hoppeana subsp. macrantha. The plants from the Alps (P. hoppeana subsp. hoppeana) and those from Calabria are diploid. The Calabrian populations, previously included in P. hoppeana subsp. macrantha, are shown to belong to a separate species, P. leucopsilon. The principal component analysis, based on 25 morphological characters, allowed distinguishing clearly four groups. An allozyme study using 10 enzyme systems revealed 7 polymorphic loci with a total of 20 alleles, some of them exclusive at regional level, others shared between populations showing similar morphological features. The genetic differentiation between populations was relatively high. The obtained dendrogram supports recognition of the morphologically defined taxa.     

Seed coat morphology and its systematic significance in Juncus L. (Juncaceae) in Egypt

The seed morphology of nine taxa of Juncus from Egypt has been investigated using light and scanning electron microscopy, to determine the importance of seed coat features as taxonomic characters. Macro- and micromorphological characters, including seed shape, color, size, seed appendages, epidermal cell shape, anticlinal boundaries, and outer periclinal cell wall and secondary cell wall sculpture are presented. Four types of seed appendages are recognized: (i) seeds with two appendages; (ii) seeds without appendages; (iii) seeds with minutely a piculate at one end; and (iv) seeds with minutely a piculate at both ends. Two types of anticlinal cell wall boundaries,(i) raised-channeled, straight and (ii) raised, straight or sinuous, and three different shapes of outer periclinal cell wall are described: (i) flat; (ii) concave; and (iii) flat to slightly concave. The secondary sculpture of the cell wall varies from striate to microreticulate or reticulate, and smooth to finely folded. Seed characters provide useful data for formulating the taxonomy of Juncus both on the subgeneric and sectional level. A key for the identification of the investigated taxa based on seed characters is provided.