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。     

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。     

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。     

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。     

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.     

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。     

中国安息香属22种植物花粉形态及其分类学意义

利用扫描电镜对中国安息香属（Styrax）22种植物花粉形态特征进行观察和分析,其中7种安息香属植物的花粉形态为首次报道。结果显示：（1）22种安息香属植物花粉类型为中型花粉（25~50 μm）和大型花粉（50~100 μm）,花粉极面观为三角形或三角圆形,赤道面观为菱形或椭圆形,萌发孔类型为3孔沟型。（2）花粉极轴长度（P）为36.28~55.56 μm,赤道轴长度（E）为16.67~36.72 μm,极轴与赤道轴的比值P/E为1.41~2.18,体积指数$ {sqrt{mathrm{P}times mathrm{E}}} $为24.59~45.17,花粉萌发沟长度为26.82~46.87 μm。（3）花粉外壁纹饰分为4类,包括网状纹饰、疣状纹饰、脑纹状纹饰和穴状纹饰。（4）根据聚类分析可将22种安息香属植物分为5个类群。研究结果表明,安息香属植物的花粉形态特征在种间存在差异,可作为种间鉴定及分类的重要依据。     

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。     

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.     

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。     

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.     

Relationship between activities of key enzymes involved in starch synthesis and accumulation in maize inbred lines during grain filling

Time course of starch production and the key enzyme activities in the grains of four maize inbred lines (two high-starch and two low-starch lines) were studied. Accumulation of grain starch and its components in four maize inbred lines rose continuously after pollination and increased as a sigmoid curve during grain filling. The accumulation rates showed single-peak curves. The accumulation rates of starch and its components reached their peaks on 25–32 days after pollination (DAP), respectively. Activities of adenosine diphosphoglucose pyrophosphorylase (AGPPase) and starch synthase in the grains of four lines followed single-peak curves with the peaks on 24–31 DAP. The highest activity of the starch-branching enzyme (Q-enzyme) in the grains of both high-starch lines appeared on 23 DAP, but that of both low-starch inbred lines showed double-peak curves, the peaks being at 15–20 DAP and 30–35 DAP. There was significant positive correlation between AGPPase, soluble starch synthase (SSS), and starch granule-bound synthase (GBSS) activities. The results indicated the Q-enzyme had different expression patterns in the high-and the low-starch maize inbred lines, and that AGPPase, SSS, and GBSS activities were significantly and positively correlated with amylose, amylopectin, and starch accumulation rates in all lines. This text was submitted by the authors in English     

黄独脱毒苗种质离体保存及其遗传稳定性和病毒变化的初步研究

以黄独脱毒苗带芽茎段为外植体,以MS为基本培养基,采用正交实验和单因子实验方法研究了无机盐水平、蔗糖、甘露醇和植物生长抑制剂PP₃₃₃对黄独脱毒苗离体保存的影响。结果表明,黄独脱毒苗带芽茎段在25±1℃下保存于附加2.0 mg·L^-1 KT、0.5 mg·L^-1 NAA、30 g·L^-1蔗糖、20 g·L^-1甘露醇和4 mg·L^-1 PP₃₃₃的1/4MS培养基上,180 d后其成活率可达90%以上。离体保存后的脱毒苗经形态指标和生理生化指标以及RT-PCR分析测定没有发生遗传变异,也没有检测到PVY病毒。本实验结果为药用植物黄独脱毒苗的种质保存提供了一条简单有效的途径。     

Effect of carbon dioxide enrichment on chlorophyll content, starch content and starch grain structure in Trifolium subterraneum leaves

Trifolium subterraneum (cv. Dinninup) responds to enriched atmospheric CO₂ in a manner similar to that described by Madsen (1968 and 1976) for tomato. In immature leaves, the total chlorophyll content per unit dry weight and the chlorophyll a:b ratio are significantly lower in plants grown at 0.10 vol% CO₂. Although fully expanded mature leaves partially overcome the deficit in chlorophyll content, the chlorophyll a:b ratio remains substantially lower in these high CO₂ grown plants. The large amount of starch accumulated as irregularly shaped grains appears to disrupt normal chloroplast structure in clover plants grown in enriched atmospheric CO₂. These results indicate the chlorotic appearance of leaves from high CO₂ grown clover plants is due to a decrease in chlorophyll content per dry weight possibly resulting from large starch grains and starch accumulation altering normal chloroplast structure and function.     

山茶属油茶组、短柱茶组和红山茶组植物叶的红外光谱分析及其分类学意义

利用傅立叶红外光谱仪和OMNI采样器直接、迅速、准确地测定山茶属Camellia4组63种2变种植物叶片的红外光谱,结果表明：各分类群（种）的红外光谱具有高度特异性,其红外光谱图的变化可以作为山茶属植物属下的分类依据之一。这也暗示了利用标准红外光谱图库,可以区分和鉴定出山茶属植物的种类。经主成分分析后的红外光谱数据构建的树型聚类图与先前的形态分类结果大体一致,能将油茶组sect.Oleifera和短柱茶组sect.Paracamellia植物明显区分,并且各组中亲缘关系较近的种聚在一起。因此支持它们作为两个独立的组处理。但是,红山茶组sect.Camellia内的滇山茶亚组subsect.Lucidissima和光果红山茶亚组subsect.Reticulata植物在聚类图上很难区分,建议将这两个亚组植物进行归并。最后讨论了张宏达和闵天禄系统中存在分歧的油茶组、短柱茶组和红山茶组内的种间分类关系。     

黄独(Dioscorea bulbifera L.)不同居群叶表皮微形态特征的比较观察

应用扫描电子显微镜(SEM)对15个黄独(Dioscorea bulbifera L.)居群(11个野生居群及4个栽培居群)植株的叶表皮微形态特征(包括气孔器、表皮毛和气孔周围表皮细胞的特征)进行了观察和测量,并据此编制了15个黄独居群的检索表.观察结果表明:15个黄独居群植株叶片在气孔器外拱盖内缘类型,气孔器旋转方向,气孔长轴长度及密度和深度,叶片表皮毛的有无及类型,叶肉腺毛的长、短轴长度及密度,气孔周围表皮细胞垂周壁和平周壁的形态以及平周壁表面颗粒形状等特征上均有明显差异.气孔器外拱盖内缘有光滑和浅波状2种类型;气孔器的旋转方向分为不定向旋转、左旋和右旋3种方式;气孔长轴长度和密度的变化幅度分别为18.59～31.93 μm和86～356 mm-2.叶片表皮毛均仅存在于下表皮,可分为乳突和多细胞头单细胞柄腺毛2种类型,乳突主要分布于主脉,腺毛主要分布于二级脉和叶肉;叶肉腺毛的长、短轴长度的变化幅度分别为25.00～55.00和24.86～44.29μm,大部分居群腺毛密度的变化幅度为6～29 mm-2.叶片气孔周围表皮细胞垂周壁的形状有平直、平直隆起、平直脊状隆起、弯曲、弯曲脊状隆起和弯曲拱状隆起6种类型;表皮细胞平周壁的表面纹饰有具瘤条纹和光滑条纹2种形态,其扩散方式也有2种形式:一种为不环绕气孔且四方扩散,另一种为环绕气孔2～3周后扩散但扩散方向不定;平周壁上的颗粒形状有簇晶状、屑状、密集粉状、粉状、粒状和片状6种类型.比较分析结果显示:黄独不同居群叶表皮微形态特征的多态性较为丰富,地理分布相近的居群微形态特征的相似性较高,这些特征与黄独的各种下分类群相对应.     

Intraspecific variation of chloroplast DNA in Dioscorea bulbifera L.

Summary Restriction fragment length polymorphism (RFLP) analysis of chloroplast (ct) DNAs from 15 accessions of Dioscorea bulbifera collected from Africa and Asia was carried out using the Southern hybridization technique. Eight cloned ctDNA fragments of D. bulbifera and D. opposita, which cover 80% of the total chloroplast genome, were used as the probes to detect variation in ctDNA digested with nine restriction endonucleases. Ten variable sites, located in the large and small single-copy regions, were disclosed among the 15 accessions, of which six showed base substitution and four carried length mutation. Positions of the latter mutations were determined on the physical map of ctDNA. Based on these results, chloroplast genomes of the 15 accessions could be classified into nine types. Their phylogenetic relationships are assumed to be as follows: (1) African and Asian chloroplast genomes diverged from each other at the earliest point in time; (2) E-type chloroplast genome, occurring in the south-east edge of the Asian continent, appears to be the most ancient among all the Asian chloroplast genomes; and (3) four chloroplast genomes, found in Asian insular regions, are probably derived independently from the E-type genome. The discrepancy between the taxonomic relationship and the proposed chloroplast genome phylogeny of the present materials is noted.