豚草花粉扫描电镜观察

豚草是一种一年生疫病杂草,其花粉(花粉粒直径约15-20微米,外壁具刺)是“枯草热”症的主要致病因子,人称豚草花粉症。本页图象显示了豚草花粉的形态特征。1.花粉粒各面观及形状,880X;2.3.花粉粒极面观(箭头示萌发孔,2.4700X,3.3927X);图4-6.花粉粒赤道面观(4.5000X,5.5000X,6.4023X);7.萌发孔 10000X):8.花粉粒之间相连的分泌物“胞问连丝”,5000X);9.外壁刺     

刺五加、无梗五加花粉的亚显微形态学研究

用扫描电子显微镜观察了刺五加和无梗五加花粉的亚显微形态特征。花粉粒的赤道面观呈近圆形,极面观呈三裂圆形,具三孔沟。无梗五加、刺五加雄株的花粉表面纹饰为网状;刺五加两性株的花粉的表面纹饰亦呈网状,但有些花粉网脊不连续。无梗五加的花粉粒大小为26.5μm×27.4μm;刺五加雄株的花粉粒大小为21.1μm×22.1μm;刺五加两性株的花粉粒大小约为21.6μm×23.9μm。研究结果表明,无梗五加和刺五加雄株花粉的亚显微形态特征支持传统的属级和种级水平的分类;刺五加两性株某些花粉粒亚显微形态的独特表现可能与其发育不正常有关。     

木兰科16种含笑属植物的花粉形态

该研究对含笑属5组16种植物(其中:峨眉含笑、多脉含笑、蔼和含笑、毛果含笑、南亚含笑、展毛含笑、阔瓣含笑和壮丽含笑等8种为首次报道)的花粉样品进行了扫描电子显微镜观测,并对其花粉粒形态及大小性状进行统计分析,以揭示木兰科含笑属植物的花粉形态特征,探讨其系统分类学意义。结果显示:含笑属植物的花粉粒形态均为两侧对称,异极,具1远极单沟萌发孔,沟长几乎达两端,极面观为椭圆状,赤道面观为舟状,表面无脊或具脊;含笑属花粉粒表面小穿孔的密度为0.002 5~1.500 0个/μm~2,最长轴长为30.69~58.02μm、变异系数为2.85%~8.20%,最短赤道轴长为15.29~31.29μm、变异系数为4.29%~15.53%,轴比值为1.43~2.69、变异系数为2.53%~13.00%。经组间、种间和种内比较,含笑属植物的花粉粒仅在小穿孔密度和3个大小性状上存在一定的种间分类学价值。     

12种十字花科植物花粉形态研究

采用扫描电子显微镜对十字花科8属12种植物的花粉形态特征进行了观察分析.其中8种为首次报道.观察结果表明:4族8属12种十字花科植物花粉形态的一般特征为:花粉粒长球形至超长球形;极面观三裂圆形,少数四裂圆形;外壁纹饰为网状或细网状纹饰;三沟,偶四沟.12种植物的花粉可划分为5种类型:(1)花粉粒长球形,网状纹饰,三沟;(2)花粉粒超长球形,网状纹饰,三沟;(3)花粉粒长球形,细网状纹饰,三沟;(4)花粉粒超长球形,细网状纹饰,三沟;(5)花粉粒长球形,三或四沟,网状纹饰.十字花科花粉形态特征在不同族间、不同属间以及同属不同种间均没有明显规律,在十字花科分类过程中,不宜单独以花粉形态特征作为依据.     

厚朴基原植物及其4个近缘种的花粉鉴定

采用扫描电镜对2种厚朴基原植物(厚朴Magnolia officinalis Rehd.et Wils.、凹叶厚朴M.officinalis Rehd.et Wils.var.biloba Rehd.et Wils.)及4种近缘植物(玉兰M.denudata Desr.、紫玉兰M.liliiflora Desr.、望春玉兰M.biondii Pampan.、荷花玉兰M.grandiflora L.)的花粉形态、表面纹饰和大小进行了观察研究。结果显示:(1)6种植物的花粉粒均为单粒,具远极单萌发沟,沟长,直达两端,左右对称,异极;侧面观均为舟形,两端较尖,赤道面观为椭圆形或近椭圆形,极面观均为近圆形;外壁均具小穴状或网状纹饰。(2)厚朴的小穴状纹饰小而浅,不明显;凹叶厚朴的小穴状纹饰小但较深,也不甚明显;相比之下,紫玉兰、玉兰、望春玉兰和荷花玉兰的花粉粒表面密布不规则隆起及深穴点,明显。(3)6种植物花粉粒由大至小依次为:荷花玉兰凹叶厚朴厚朴玉兰紫玉兰望春玉兰。3种不同的花粉处理方法中,自然干燥法能清晰地观察到花粉的扫描电镜特征,此方法优于戊二醛固定法和叔丁醇真空冷冻干燥法。本研究结果为厚朴中药资源的基原植物及其近缘种鉴定提供了新的证据,也为现代植物从种及亚种级水平分类提供了参考。     

中国苏铁属花粉形态研究

对中国苏铁属花粉进行了光镜和扫描电镜观察。花粉中等大,极轴长２６．５－３５．７μｍ,赤道轴长２０．６－２６．４μｍ;极面观椭圆形至近圆形,赤道面观船形或肾形,具远极单沟,达两端,其开闭和形状随花粉干燥或潮湿而变化,内部具多种不规则突起,两端具皱纹;远极面外壁光滑或稀具微突起,近极面具穿孔,孔穴或蜂窝状纹饰。     

新疆胡颓子属三种植物的花粉形态及其分类学意义

该文采用主成分分析和聚类分析方法,运用扫描电镜对新疆胡颓子属(Elaeagnus Linn.)落叶组大果沙(E. moorcroftii)、尖果沙枣(E. oxycarpa)和沙枣(E. angustifolia)共计18个样品的花粉形态进行了观察和研究;全面描述了新疆胡颓子属3个种花粉的极轴长、赤道轴长、极面观、赤道面观、孔沟形态和外壁纹饰等形态特点,并对其进行数据分析,通过对聚类结果的比较,讨论不同孢粉学特征对分类结果的影响。结果表明：(1)3个种的花粉均为中等大小;萌发孔类型均为三孔沟型。(2)花粉极面观形状从三角形、钝三角形到圆三角形;赤道面观形状从菱角形、半圆形到扁圆形;外壁纹饰从皱波状到穴状。(3)以筛选出的5个反映花粉形态的主成分指标进行聚类,结果显示所选指标不能区分种;以代表花粉形态的极面观形态和赤道面观形态为指标进行聚类同样也无法区分3个种;以花粉粒大小为指标进行聚类发现,大果沙枣的花粉大小可以区别于其他2个种。研究表明除了大果沙枣花粉的大小,尖果沙枣和沙枣的花粉形态不宜直接应用于种的划分。该研究结果为新疆胡颓子属落叶组植物花粉的种间鉴定和品种划分以及进化关系的研究提供了孢粉学依据。     

苹果四倍体品种天星的花粉形态及胚囊发育特征研究

利用扫描电子显微镜(SEM)和激光扫描共聚焦显微镜( LSCM)技术对二倍体富士苹果及其四倍体芽变品种天星的花粉性状及胚胎发育特征进行了观察与研究,结果表明:四倍体天星品种的畸形花粉率为10.27％,明显高于富士,花粉萌发率低,为62.42％.2个品种的花粉粒大部分侧面观为长椭圆形,具3沟型萌发孔沟,两极端形状宽而平整,极面观为三角形,但四倍体天星的花粉粒的极轴长和赤道轴长均大于二倍体富士,但P/E值小,差异显著,其花粉粒形状不及二倍体富士规则且饱满程度也低.四倍体天星的花粉表面为纵向条状纹饰,有少量分叉和穿孔,花粉外壁略显粗糙,不如二倍体富士的外壁光滑.天星和富士均为蓼型胚囊,二者均存在异常胚囊现象,天星的异常胚囊现象包括极核位置异常、极核数目异常、卵器结构异常、胚囊内有多个发育滞后的细胞等;而在富士中仅发现少数胚囊结构不完整的现象.     

几种党参属植物及其近缘种花粉形态的比较

对6种桔梗科（党参属Codonopsis4个种以及桔梗属Platycodon和风铃草属Campanula各1种）花粉进行了光镜及扫描电镜的观察比较,发现党参属不同种花粉的形态特征很不相同,易于区别,如党参花粉极面观多为7裂圆形,外壁形面具乳突状的短刺,川党参花粉极面观圆形,刺在沟的两旁排成两列,小花党参花粉极面观近圆形至7裂圆形,外壁表面的刺比其它种的都大,鸡蛋参花粉外壁表面的刺柔软而稍为弯曲,其长度为上述各种刺的数倍,桔梗属和风铃草属花粉与党参属花粉的差异更大,桔梗属花粉粒扁球形,极面观五角形,少数四或六角形,风铃草属花粉粒更为特殊,极面观近圆三角形,具3孔,花粉外壁的刺不仅锐利而且很粗,花粉形态在党参属不同种间以及党参属与桔梗属和风铃草属之间的差异为其分类学提供了进一步的孢粉学资料。     

中国15种变豆菜属植物的花粉形态及系统学分析

利用光学显微镜和扫描电子显微镜对变豆菜属15种植物的花粉形态进行观察。结果表明,变豆菜属15种植物的花粉大小为（28.51~54.29） μm~（12.23~28.98） μm,极轴与赤道轴比值（Polar axis/Equatorial axis）为1.48~2.46,具三孔沟。花粉粒赤道面观有近矩形、赤道收缩形、长椭圆形等类型,其中近矩形和赤道收缩形占多数;极面观为圆形或三角圆形。在扫描电镜下,其外壁表面纹饰为网状。我们研究结果支持在伞形科变豆菜亚科中,变豆菜属植物的花粉具有中等进化、比较进化的形态特征,花粉形态可为个别物种的分类处理提供孢粉学证据。     

盖裂木属两种植物花粉形态观察

利用光学显微镜、扫描电镜和透射电镜观察了盖裂木属两种Talauma gloriensis和T.mexicana的花粉形态。花粉粒具远极单萌发沟,椭圆球形,外壁较光滑或略粗糙且具小穴状雕纹。在透射电镜下,花粉外壁可分为覆盖层、柱状层和基层,外壁-2明显,且厚度不均匀。在远极面萌发沟区域,外壁逐渐减薄,最后覆盖层和柱状层消失,仅残留基层。T.gloriensis的柱状层内部空间较小,多由颗粒组成,而T.mexicana柱状层中有发育较好的小柱,与覆盖层和基层连接。     

美乐多（Melodorum fruticosum Lour．）花粉形态观察

利用扫描电子显微镜（SEM）和透射电子显微镜（TEM）观察了美乐多（Melodorum fruticosum）的花粉形态特征。美乐多花粉为球形或扁圆形的单粒花粉,外壁纹饰为微褶皱状,有点状凹陷,无任何萌发孔或萌发沟。花粉外壁由外壁外层包括覆盖层（连续）、覆盖下层、基足层（1～3层薄片层结构,偶断裂或扭曲至6～10层）和外壁内层（连续）组成。其中,覆盖下层,其厚度为整个花粉外壁厚度的1／2,为混合型结构,即小柱状和颗粒状同时存在,但以颗粒状为主。花粉内壁分为内壁外层和内壁内层,其厚度逐渐变薄。美乐多的花粉特征（单粒、无萌发孔或沟、覆盖层连续、基足层为薄片层结构、花粉外壁内层薄等）与紫玉盘族其他类群一致。     

Transition within the exine of Nothofagus Blume

Pollen grains with bulged areas on their proximal and distal faces were observed in some species of Nothofagus Blume in the light and electron microscopes. Pollen grains sectioned meridionally are distinctly transitionary in character in the individual strata within the exine of one pollen grain. The tectum in the apocolpia is considerably thinner than in the mesocolpia, The thickness and the character of the bacular layer in the mesocolpia differ greatly from those of the apocolpia. The foot layer, thick and always present in the mesocolpia, is entirely lacking in the apocolpia. The significant difference in the structure and thickness of the bacular layer, as well as the partial absence of the foot layer in one pollen grain, influence the cohesion between the individual strata of the exine in the apocolpia. The cohesion between the tectum and underlying, globular stratum in the central part of the apocolpia is poor, which facilitates the separation of the tectum and its bulging at that area.     

蓼科花粉外壁超微结构的研究

用扫描电镜和透射电镜对蓼科6属15种的花粉壁构造的特点进行了观察和研究。结果表明：(1)外壁纹饰有如下几种：颗粒-穿孔,微刺-穿孔,微刺-穿孔-光滑,颗粒-穿孔-光滑,细网状,粗网状,皱块状,鼓锤状;(2)外壁结构分化成两个明显的层次,即外壁外层以及外壁内层。其外壁外层由覆盖层、柱状层和基层组成。然而,由于每一部分发育状况的不同而导致外壁结构有各种变化,如无覆盖层或无外壁内层。     

A Study on Pollen Morphology and Ultrastructure of Subfamily Castaneoideae (Fagaceae) in China

The present paper describes the pollen morphology of 45 species of the subfamily Castaneoifeae (including genera Castanea, Castanopsis and Lithocarpus) from China. The pollen grains were all examined with light microscope, scanning electron microscope and transmission electron microscope. Pollen grains of the subfamily are prolate, subprolate or perprolate, (14.7-23.1)× (8.4 -18.9) μm in size, 3-colporate, the exine in 2-layered, 0.9-1.9μm thick, indistinctly ornate, striate-rugulose or crass-striate, sexine and nexine almost equal in thickness, the sexine consists of tectum, bacules and endonexine under TEM. On the basis of very similar pollen shape, pollen size, type of aperture and exine structure and also other characteristics of plant morphology of the genera Castanea, Castanopsis and Lithocarpus, the present authors tend to support the opinion that they all fall into the samesubfamily, Castaneoideae.     

五种木兰属植物的花粉形态

对木兰属(Magnolia)5种花粉进行了光学显微镜观察,形态相似。扫描电镜下观察,花粉外壁均为小穴状纹饰,荷花玉兰(M．grandiflora)略为粗糙。透射电镜下观察,5种花粉外壁均可分为覆盖层、柱状层和基层。覆盖层不连续,有小穿孔。在远极面萌发沟区域,外壁逐渐减薄,最后覆盖层和柱状层消失,仅残留基层。柱状层内部空隙较小,多由颗粒构成,处于小柱发育的初级阶段。荷花玉兰和玉兰萌发沟区域下有明显的外壁-2。木兰属花粉属于原始类型的代表。     

Pollen Morphology of the Subtribe Hyoscyaminae (Solanaceae)

The pollen morphology of 12 species representing 6 genera was examined under the light; scanning and transmission electron microscope. According to form of aperture; sculpture and structure of exine; the palynological relationships among the 6 genera are discussed. 1. Scopolia Jacq. (plate 1:1-4) Pollen grains subspheroidal or irregular; 43.7-49.6 μ in diameter; nonaperturate; Exine about 1.2-1.5μ thick; verrucate; with verrucae unequal in size; spinulose or granular. Stratification indistinct; with no columella layer visible under TEM. 2. Anisodus Link et Otto (plate 1: 5-12) Pollen grains subspheroidal; 43.4-48.7 μ in diameter; nonaperturate. Exine 1.5-1.8 μ thick; verrucate; with verrucae unequal in size; spinulose or smooth. Stratification indistinct under TEM. 3. Atropanthe Pascher (plate 2: 1-4) Pollen grains subspheroidai or spheroidal; triangular-circular in polar view; oblong in equatorial view; 47.2-49.3 μ ×39.8-47 μ; 3-colpate; colpi wide or narrow; colpus membranes finely granular. Exine with irregular short-stick sculpture; 2.3μ thick; distinctly 2-layered; columella layer clearly visible; sexine thicker than nexine under TEM. 4. Przewalskia Maxim. (plate 2: 5-8) Pollen grains subspheroidal; triangular-circular in polar view; oblong in equatorial view; 39.2-40.3 μ × 36.4-42.8 μ ; tricolporate; ora lalongate; colpus membranes granular. Exine reticulate; 2-layered; 2u thick; columella layer distinct; sexine and nexine equal in thickness under TEM. 5. Physochlaina G. Don (plate 2: 9-12; plate 3: 1-12) Pollen grains polymorphic; usually subspheroidal; 36.5-39.4μ in diameter; aperture varying from nonaperturate (P. macrophylla); 3-4 rugose (P. physaloides) to 3-colporate (P. praealta). Exine 1.5-2μ thick; reticulate; smooth or with spinulose or verrucous processes under SEM; distinctly 2-layered; or without stratification; columella layer differentiated or not. 6. Hyoscyamus Linn. (plate 4: 1-9) Pollen grains subspheroidal; circular-triangular in polar view; oval in equatorial view; 39.9-41.8 μ × 38.7-4.2 μ; tricolporate. Ora orbicular; colpus membranes finely granular or with striate processes. Exine reticulate or striate-rugulate; 2-2.3μ thick; distinctly 2-layered; columella layer developed. The dendrogram (Fig. 1) indicates probable phylogenetic relationships among the sixgenera in the subtribe Hyoscyaminae.     

水雍科植物的花粉形态研究

应用光学显微镜、扫描电镜和透射电镜对世界水雍科6种植物的花粉形态进行了观察。水雍科植物花粉为舟形或船形,具远极单沟萌发孔类型,外壁纹饰通常为浅网状至网状,稀为小刺状纹饰,外壁外层由覆盖层、柱状层和基层组成,覆盖层厚。水雍科植物花粉外壁纹饰表现了从小刺状向网状的过渡。该科花粉为远极单沟,覆盖层厚,具小刺等特征反映了其与水鳖科和泽泻目花蔺科的密切联系,而该科花粉外壁纹饰多为网状则与茨藻目植物接近。这一结果支持将水雍科从茨藻目中分出作为一个独立的目处理的观点。此外,水雍科植物的花粉大小、纹饰类型、网眼大小与深浅等方面的差异对种级分类有一定意义。     

A Comparative study on pollen exine ultrastructure of Nothofagus and the other genera of Fagaceae

The genus Nothofagus is mainly distributed in South America and New Zealand. The present paper describes its pollen exine ultrastructure and compares the exine ultrastructure with that of the other genera of Fagaceae. The pollen grains were examined using ultrathin sectioning technique under transmission electron microscope. The study shows that the pollen exine ultrastructure of Nothofagus differs from that of the other genera of Fagaceae by its exine structure and thickness, type of aperture, and ornamentation. The pollen exine of Nothofagus is thin and possesses granular bacules, regular foot layer and tectum, spinulate ornamentation, and the endexine is usually visible at poral area, and 5～8 colpate. The pollen exine of the other genera of Fagaceae possesses entire bacules, irregular foot layer and tectum, granulate and tuberculate ornamentation, thicker endexine, and is 3-colporate ( 3-colpate or 3-colporoidate). The pollen exine ultrastructure of Nothofagus may belong to primitive type. The pollen exine ultrastructure data support Kuprianova’s opinion that Nothofagus should be separated from Fagaceae and established as a monogenetic family, i.e. Nothofa-gaceae.     

Studies on Pollen Morphology of Pulsatilla Mill.

Pollen grains of 18 species of Pulsatilla in Ranunculaceae distributed in Asia and Europe were examined by LM and SEM, and exine ultrastructure of tricolpate pollen grains of P. chinensis and of pantoporate pollen grains of P. campanella was examined by TEM. Pulsatilla pollen is divided into four major types based on the aperture character, i.e. tricolpate, di- and tricolpate, pantocolpate and pantoporate. The revolutionary trend of pollen types is as follows: tricolpate→pantocolpate→pantoporate. Surface spinulate and perforate. According to density and size of sptnulae and distribution of perforation, the pollen grains of the genus can be divided into two groups. Thin sections of P. chinensis and P. campanella show endexine thickened at colpi and ora. Ektexine consists of a foot layer, a collumellae layer and a continuous, perforate tectum. The columallae layer is thicker than foot layer and tectum. Pollen morphology of Pulsatilla is similar to that of Anemone, but different in the distribution of spinules and perforation. Pollen information supports Wang’s view about systematic arrangment of species of Pulsatilla in China.