茄子花粉形态特征及分类研究

应用环境扫描电镜对28份茄子栽培种及近缘种花粉形态、外壁纹饰等作了系统观察和比较分析。结果表明,所有供试材料花粉均为长球形,具3萌发沟,以等间距环状分布,沟延伸到两极;花粉外壁纹饰均为颗粒状。不同材料花粉粒在大小、外壁纹饰特征方面存在不同程度的差异,花粉粒大小可以作为推断茄子栽培种内不同果形品种演化的依据。对一些典型的花粉形态性状进行聚类分析,结果将茄子分为栽培种和近缘种两大类,聚类分析结果与传统分类结果具有一定的一致性。     

栽培甜菜花粉发育过程的超微结构

利用透射电镜技术对栽培甜菜（Beta vuigaris）花粉发育过程进行了超微结构观察。结果表明,在小孢子母细胞减数分裂期间,细胞内发生了“细胞质改组”,主要表现在核糖体减少,质体和线粒体结构发生了规律性变化。末期1不形成细胞板,而是在2个子核间形成“细胞器带”。“细胞器带”的存在起到类似细胞板的作用,暂时将细胞质分隔成两部分。四分体呈四面体型,被胼胝质壁包围。小孢子外壁的沉积始于四分体晚期,至小孢子晚期外壁已基本发育完全。单核小孢子时期,细胞核大,细胞器丰富。二细胞花粉发育主要表现在生殖细胞壁的变化上,生殖细胞壁上不具有胞间连丝。成熟花粉为三细胞型,含有1个营养细胞和2个精细胞。精细胞具有短尾突,无壁,为裸细胞,每个精细胞通过2层质膜与营养细胞的细胞质分开。生殖细胞与精细胞里缺乏质体。     

The Pollen Morphology in Relation to the Taxonomy and Phylogeny of Fagaceae

The present paper deals with the pollen morphology of 103 species belonging to sixgenera-Castanea, Castanopsis, Lithocarpus, Quercus, Fagus and Trigonobalanus in threesubfamilies-Castaneoideae, Quercoideae and Fagoideae. All pollen grains were examinedunder light microscope and scanning electron microscope, and those of some species were ex-amined under transmission electron microscope. The results may be summarised as follows:1. Pollen morphology of Fagaceae, seems to support division of the family into threesubfamilies. Fagoideae, Castaneoideae and Quercoideae.2. Four types of pollen grains are recognized in Fagaceae:1) Fagus-type (representative genus: Fagus): pollen granis are oblate-sphaeroidal,(31.5-39.9) x (35.7 46.2) μm in size, 3(-4)-colporate, peritreme or goniotreme, granulate-ornate under LM., granulate or verrucate under SEM.2) Trigonobalanus-type (T. doichangensis): pollen grains are suboblate-sphaeroidal,(23.1-29.4) ×(25.2-29.4) μm in size, 3-colporate, goniotreme, obscurely granulate-ornateunder LM, densely granulate or verrucate under SEM.3) Quercus-type (Quercus): pollen grains are subspheroidal-subprolate, (21-44.3)× (16.8-39.9) μm in size. 3-colporoidate (-3-colpate), peritreme, crassgranulate or finely-gra-nulate under LM, tuberculate verrucate or spinate under SEM.4) Castanea-type (including Castanea, Castanopsis, Lithocarpus): Pollen grains areprolate-supraprolate, (14.7-23.1)×(10.5-16.8)μm in size; 3-colporate, peritreme, obscu-rely ornate or subpsilate, under LM, rugulose, striate-rugulate or crass-striate under SEM.3. Pollen grains of Cyclobalanopsis age very similar to those of Quercus, and there-fore we support the treatment of Cyclobalanopsis as a subgenus of Quercus.4. On the basis of shape, type of aperture and exine structure, pollen of Trigonobalanusis distinguishable from those of the other genera in Fagaceae and it may be a new type of Fagaceae;5. On the basis of pollen morphology, morphological characters and geological stratification a scheme of phylogeny of Fagaceae is here presented.     

荞麦水合花粉和花粉管中的被膜小泡

荞麦水合花粉粒和生长中的花粉管中内质网潴泡形成的囊袋状结构较少见,但内质网囊袋中含有丰富的被膜小泡,直径约为100－150nm。刚刚形成的花粉管中,被膜小泡主要来自于花粉粒营养细胞的细胞质。生长中的花粉管的被膜小泡可由高尔基体分泌形成。另外还观察到内质网的碎裂也是荞麦花粉管中产生被膜小泡的一种机制。花粉管的被膜小泡中含有花粉管壁的前体物质,与花粉管的壁融合参与花粉管的生长。被膜小泡可能含有与脂体和造粉质体水解有关的酶,参与此类物质的降解。荞麦花柱和柱头细胞内含物的解体物质参与花粉管的生长。     

扇脉杓兰花粉超微结构及花粉管生长的观察

为明确扇脉杓兰花粉形态结构及雄性生殖特性,利用扫描电镜、透射电镜和荧光显微镜对花粉形态和超微结构及花粉管生长过程进行观察。结果表明:(1)扇脉杓兰单粒花粉长球形,表面光滑无特征纹饰,有少量胶黏物质,一些表面有2个或以上的深凹陷,凹陷内有球形突起的内容物。(2)花粉壁分为由棒状的基柱小单元组成的外壁和纤维素果胶组成的内壁,有覆盖层;生殖细胞近圆形,细胞核大而致密;营养细胞多弧形,核质分散;花粉粒细胞质含有大量的线粒体、质体和小泡等细胞器,淀粉、蛋白质和多糖含量丰富。(3)花粉管萌发后沿子房壁方向伸长,授粉20d花粉管伸长生长并不明显,授粉30d伸长的花粉管中出现大量胼胝质塞,并且伸长方向转为胚珠中间,花粉管逐渐接近胚珠,在授粉后50d基本完成受精作用。研究认为,扇脉杓兰花粉发育正常,不阻碍有性生殖过程。     

On the Ultrastructure of Pollen Exine in Metasequoia Hu and Cheng

Metasequoia is endemic to China. Present study deals with ultrastructure of pollen exine of M. glyptostroboides Hu et Cheng, and in comparision with other genera of the family. Pollen grains of Metasequoia are spheroidal or subsphoroidal and 27.8(24.3–32.3) μm in diameter. There is a papilla in the distal face. The papilla is wide at the base, 3.5–5.2 μm high, with pointed and circular end and the base crooked toward one side. Exine is about L5 μm thick, layers distinct, Nexine is as thick as sexine. Surface weakly granulate. According to observation by SEM, exine is covered with fine granules and rather coarse tuberculae. The former can be easily separated from the latter. The loose and uneven tuberculae are provided with minute spinules on the surface and generally fall off after acetolysis. The fine and dense granulae, however, remain intact after acetolysis. The study by TEM shows that ektexine is made of granules densely arranged and connected with each other. In addition, sparse Ubisch bodies are unevenly distributed on granular layer with geminate surface. The thick endexine, is composed of 10–15 lamellae. It is worthy to note that all lamellae possess tripartite structure. But lamellae of endexine in other genera of Taxodiaceae have no tripartite structure except the lamella near ektexine. Number of lamella and thickness of endexine in Metasequoia differ from those of other genera in Taxodiaceae; for example endexine with 8–10 lamellae in Taxodium, 8–9 lamellae in Sequoia, 6–7 lamellae in Glyptostrobus, 6–8 lamellae in Cunninghamia, about 16 lamellae in Cryptomeria etc.     

甘草花粉超微鉴定及花粉活力、柱头可授性荧光显微镜观察

对甘草的有性生殖特性进行了研究,利用扫描电子显微镜对乌拉尔甘草、光果甘草和胀果甘草花粉的超微结构进行观察,利用荧光显微镜确定乌拉尔甘草的授粉方式、花粉生活力和柱头活性以及授粉后受精时间.结果表明,花粉超微结构为甘草的鉴别提供了一定的形态学依据;甘草的授粉方式属于闭花受精;花粉生活力在每天12:00时最强,去雄后超过4d的柱头已经不具备接受花粉的能力;对授粉后不同时间的雌蕊进行研究得出授粉后6h花粉管进入胚珠进行受精.     

Studies on Pollen Morphology and Exine Ultrastructure in Cephalotaxaceae

The pollen morphology of Cephalotaxaceae was examined with LM, SEM and TEM. Pollen grains in this family are spheroidal or subspheroidal, rounded in polar view, but usually wrinkled with irregular shape. Pollen size is 22.6- 34.8 μm in diameter. There is a distinct or indistinct tenuity on distal face. The tenuity occasionally slightly rises above the outline of pollen grains, but often sukened. Exine rather thin, 1—1.5μm thick, layers obscure, surface of pollen grains is nearly psilate or weakly granulate. Under SEM exine is covered with fine and dense granules, and sparse Ubisch bodies are found on the granular layer. The Ubisch bodies are provided with minute gemmate processes on the surface. Acorrding to our observation under TEM, exine consists of ectexine and lamellate endexine, with the former divided into outer ectexine of granules densely arranged and inner ectexine of loosely arranged microgranules. Granules of the outer ectexine are relatively thick, and connected with each other, forming a structure just like tectum or separate from each other. Microgranules of the inner ectexine are distinct or indistinct. Endexine is provided with 5- 7 lamellae. As far as information of pollen morphology is concerned, Cephalotaxus oliveri is rather special in the Cephalotaxaceae. First, the tenuity in pollen grains occupies one half of the distal part, much larger than that of the other species in the family. Second, the ectexine in Cephalotaxus oliveri may be divided into two distinct layers, outer ectexine and inner ectexine. The former is made of a layer of sporopollenin masses, which are connected with each other to form tectumlike structure, while the latter consists of a layer of loosely arranged granules or small segments of sporopollenin. The inner ectexine is different from that of other species by having a thicker layer of sporopollenin granules. Based on these two features, we support the division of Cephalotaxus into two Sections, Sect. Pectinatae and Sect. Cephalotaxus. Pollen grains of Cephalotaxaceae are similar to those of the Taxaceae in having spheroidal shape and the tenuity on its distal face. These characteristics strengthen the evidence for a close relationship between the Cephalotaxaceae and Taxaceae. Although pollen grains of the Cephalotaxaceae and Taxaceae are similar in some characteristics, they have obvious differences in , for example, size of tenuity, the fine structure of Ulbisch bodies and of the outer and inner ectexine. On the basis of pollen morphology, the present author considers theCephalotaxaceae slightly more primitive than the Taxaceae.     

西瓜花粉壁超微结构与花粉ATP酶细胞化学定位

研究了西瓜花粉壁超微结构以及单核花粉液泡化时期ATP酶活性超微细胞化学定位。花粉壁的外壁分为外层和内层,外层包括覆盖层、基粒棒和基足层等三层,内层只包含一层。外层电子密度相对较小,内层电子密度相对较大;外层与内层之间有缝隙。ATP酶活性反应产物主要分布在细胞质基质、质体、内质网和花粉内壁中。     

西瓜花粉壁超微结构与花粉ATP酶细胞化学定位

研究了西瓜花粉壁超微结构以及单核花粉液泡化时期ATP酶活性超微细胞化学定位。花粉壁的外壁分为外层和内层 ,外层包括覆盖层、基粒棒和基足层等三层 ,内层只包含一层。外层电子密度相对较小 ,内层电子密度相对较大 ;外层与内层之间有缝隙。ATP酶活性反应产物主要分布在细胞质基质、质体、内质网和花粉内壁中     

Ultrastructure of Microfilaments in Pollen and Pollen Tubes of Hosta Ventricosa (=H. voerulea)

Ultrastructure of microfilaments in pollen grains and pollen tubes of Hosta ventricosa (=H. coerulea) was investigated. Results indicate that microfilaments with conventional chemical fixation are preserved only in pollen grains, but destroyed in pollen tubes. Microfilaments treated with phalloidin before chemical fixation are found preserved in pollen tubes. In pollen grains a pronounced organization of parallel microfilaments appeared in bundles with its distribution characteristics is always restricted to their functional domains where bundles were in close contact with the vegetative nucleus. In young pollen tubes cytoplasmic bundles of microfilaments appeared also to pass close to the surface of mitochondria, plastids, endoplasmic reticulum, vesicles and small vacuoles, and always associated with lipid bodies. These findings strongly indicate that there is a relationship between microfilaments and the movement of vegetative nucleus and other organelles in the germination of pollen grains and in the growth of pollen tubes.     

Development of Pollen Grain Walls and Accumulation of Sporopollenin

By means of electron microscopy, we studied the development of pollen grain walls in Calendula officinalis L., Dimorphotheca aurantiaca DC., and Cichorium intybus L. (Asteraceae). As a reference, we studied the plants from the families Schisandraceae (Schisandra chinensis (Turcz.) Baill.), Lauraceae (Persea americana Mill.), Boraginaceae (Borago officinalis L.), and Cycadaceae (Encephalartos altensteinii Lehm.). In Asteraceae, we revealed two successively initiated layers of glycocalyx that form outer and inner layers of the ectexine. The formation of endexine is contributed by plasma membrane and small vesicles. Glycocalyx in the plants from the families Schisandraceae, Lauraceae, Boraginaceae, and Cycadaceae was found to consist of radially arranged helical cylindrical units, which are receptors of sporopollenin deposition. It is assumed that the receptor-independent accumulation of sporopollenin is also possible.     

苹果地方品种花粉形态分类及聚类研究

利用扫描电镜观察了苹果属植物25个地方品种、10个野生种类型、3个栽培品种、2个杂交种共40个不同类型的花粉形态特征,根据花粉形状、极轴和赤道轴长度等11个指标,采用类平均法(UPGMA)对欧式距离进行聚类分析。结果发现:所观察花粉类型均为N_3P_4C_5类型,呈两侧对称的长球形或超长球形,花粉表面有条状饰纹和穿孔,各类型间花粉粒大小及外壁纹饰差异明显,地方品种早白海棠外壁饰纹无条纹束,区别于其他资源。聚类分析表明:在遗传距离1.30水平上,40份资源聚为9大类,地方品种与野生资源、栽培品种相互交错,部分地方品种单独聚为一类。地方品种花粉形态多样性极为丰富,除一些特异类型,花粉形态不能单独作为地方品种分类的依据,需结合其他分类方法;部分地方品种起源于新疆野苹果或者新疆野苹果与其他野生资源或者栽培种的自然杂交,部分地方品种经过相互杂交和人工选择形成其类型的多样性,具有重要的科研价值。     

五列木科和肋果茶科花粉外壁超微结构及其与山茶科的系统学关系

借助光学显微镜、扫描电镜和透射电镜对五列木科Ｐｅｎｔａｐｈｙｌａｃａｃｅａｅ和肋果茶科Ｓｌａｄｅｎｉａｃｅａｅ花粉进行了观察,并与山茶科Ｔｈｅａｃｅａｅ若干属的花粉进行了详细的比较,同时参考了猕猴桃科Ａｃｔｉｎｉｄｉａｃｅａｅ的花粉特征。研究表明,肋果茶科的花粉与山茶科的花粉具有较多的相似性,如其形状和大小与山茶科中厚皮香亚科的几乎一致;而花粉的表面纹饰（粗糙至模糊的皱波状纹饰）则与山茶属,Ｆｒｅｚｉｅｒａ属和厚皮香亚科部分属的花粉纹饰相类似。从花粉外壁的结构看,肋果茶的花粉与石笔木属和山茶属的更接近,表现为：花粉外壁层次分化明显,复盖层和柱状层均较厚,外壁内层薄。而五列木科花粉除了形状和萌发孔类型与山茶科的相似外,其纹饰特征和外壁结构均与山茶科的差异较大,如五列木科花粉表面近光滑,外壁覆盖层较簿,柱状层很不发达,外壁内层相对较厚等。孢粉学上认为,肋果茶科与山茶科具有更为密切的关系,五列木科则与山茶科较疏远。支持把肋果茶科作为一个属置于山茶科内或作为山茶科的一个亚科     

The Pollen Morphology and Exine Ultrastructure of Paeonia L in China

The pollen morphology of 9 species of Paeonia L. has been investigated with both light microscope and scanning electron microscope. In addition, the exine structure of pollen grains of Paeonia suffruticosa and P. lactiflora was examined by transmission electron microscope. Tricolporoidate aperture is an important character of the pollen grains of the Paeonia. The surface of the exine is characterized by reticulate, foveolate and irregularly tuberculate-foveolate sculpture under the SEM. Thin sections of the pollen of this genus shows that the layers of exine are complete i.e. a perforate rectum to semitectum, columellae and foot layers. The endexine is continuous, considerably thickened in the aperture areas and relatively thin or indistinct in the mesocolpia. Paeonia has been placed in Ranunculaceae. But since the beginning of this century many authors have suggested to separating Paeonia from Ranunculaceae. Pollen marphology supports such separation. In Ranunculaceae most pollen grains are tricolpate or have other types of aperture, and exine with spinules and perforations between them. In electron microscopy, the ektexine contains a foot layer, columellae, and perforate rectum, the columellar layer with two types of columellae; the endexine is generally thin. However, the columellar layer of Paeonia has only monomorphic columellae. Some authors considered that there is a close relationship between Paeonia and the Dilleniaceae, but these also differ in the characters of the pollen grains. In Paeonia the constriction of the colpus in equator is in some degree similar to that of Theaceae (Camellia sasanqua Thunb.), Guttiferae (Hypericum L.), Actinidiaceae and Rosaceae. But in the other respects they are quite different. In sum, the pollen morphology of Paeonia is unique. So the palynological information supports Takhtajan's view that Paeonia should be elevated to a family (Paeoniaceae) or order (Paeoniales).     

基于花粉形态数量分类的核果类系统关系研究

运用扫描电子显微镜(SEM)观察了李属、杏属、樱桃属和桃属的花粉形态,观察结果表明:核果类果树的花粉均为近扁球形,等极,辐射对称,极面观为三角形或钝三角形,赤面观均为椭圆形,花粉粒大小在各属间差异明显。核果类果树花粉属N3P4C5类型,3条孔沟沿极轴方向在赤道面上等间距环状分布,内孔位于沟的中央,完全独立于外壁,孔盖覆不规则的拟网状或脑纹状纹饰。供试核果类果树花粉的表面纹饰由平行条纹或不规则条脊及散落于条脊间的穿孔组成,各属间条脊的排列方式、宽窄、脊洼深浅及穿孔有无等性状上存在明显差异。根据花粉大小、表面纹饰及覆盖层穿孔等的一般演化规律,推测核果类果树由低到高的演化顺序为李属→杏属→樱桃属→桃属,并在聚类分析的基础上对属间亲缘关系进行了探讨,旨在为核果类系统关系的研究提供孢粉证据。