Pollen Morphology of Chinese Datura and Its Taxonomic Significance

The pollen grains of 11 taxa of Chinese Datura were examined under light microscope and scanning electron microscope. All of them are 3(-4)-colporate. The exine ornamentation is so distinct as to allow the identification of individual sections and species, and may be divided into three types. The division is consistent with the taxonomy based on gross morphology i.e. rugulato-reticulate (Sect. Stramonium); striate or striato-reticulate, with some granules on the surface of the lirae, or scabrous (Sect. Dutra); striate with some rings on the surface of the lirae, looking like silkworm (Sect. Brugmansia). The varieties or cultivated forms are not sufficiently distinct from each other in the pollen grains as observed in this investigation.     

Studies on Pollen Morphology of Taxaceae of China

The present study deals with pollen morphology of 4 genera and l0 species of Taxaceae in gymnosperms. Pollen grains of the family are spheroidal or subspheroidal, 20.8μm in diameter and with laptoma or papilla in the distal face. Exine is two-layered, with sexine equal to nexine in thickness, but sometimes the stratification is indistinct. The surface is scabrous or slightly granular under LM. Coarse verrucae and fine tuberculae on pollen surface are observed under SEM. From thin section, endexine is shown to have lamellate structure, and ectexine is made of verrucate elements. In Amentotaxus argotaenia, some pollen grains show remnant saccate. According to pollen morphology, this family may be divided into two tribes: 1, Pseudotaxeae (including Pseudotaxus only), and 2, Taxeae (including Taxus and Torreya). Owirg to the special feature of pollen grains in Amentotaxus the present author suggests that the genus be separated from Taxaceae and raised to the level of family, Amentotaxaceae.     

An Ultrastructural Study of Pollen Wall Ontogeny in Silene Pendula

Pollen of 41 species representing all seven genera of the Neottieae were examined by scanning electron microscopy. Except for Lecanorchis, the genera of the Neottieae constitute a natural group based on pollen morphology. Pollen occurs as single grains in the primitive species and in tetrads in the other species. Most grains are monoaperturate, porate or tenuate, and the tetrads often have irregularly shaped grains. Exine structure varies from tectate-perforate to semitectate. Lecanorchis is anomalous among the Neottieae in that it has 0–5, sunken, relatively small pores. Pollen morphology of this genus indicates that it is probably more closely related to the Gastrodieae than the Neottieae. There are at least four basic phyletic units in the Orchidaceae: the Neottioideae, Apostasioideae, Cypripedioideae, and Epidendroideae. These groups are distinguished by the presence of monads in at least their more primitive members and by their unique pollen types.     

Study on the Pollen Morphology of the Family Berberidaceae

The pollen grains of 33 species representing 11 genera of the family Berberidaceae, mostly from China, were examined with the light microscope and scanning electron microscope. Their characteritic details can be used for generic diagnosis. A pollen key to the genera based on these observations is presented. Based on the morphology, the pollen grains can be grouped into the following three types: 1. The tetrad pollen type found only in the genus Sinopodophyllum. 2. The spiraperturate pollen type found in the genera Berberis and Mahonia. 3. The tricolpate pollen type found in the genera Diphylleia, Jeffersonia, Nandina, Dysosma, Caulophyllum, Leontice and Epimedium. A diagnostic key to the pollen grains of genera in the Berberidaceae. 1. Pollen grains single 2. Pollen grains spiraperturate .................... Berberis L., Mahonia L. 2. Pollen grains tricolpate 3. Exine with spinose sculpture ........................ Diphylleia Michx. 3. Exine with non-spinose sculpture 4. Exine with striate or striate-reticulate sculpture ...... Jeffersonia Barton 4. Exine with reticulate sculpture 5. Exine around colpus with distinct thickening ........ Nandina Thunb. 5. Exine around colpus without thickening 6. Pollen grains larger (45—50)×(32.5—37.5)μ 7. Colpus with membrane ................ Dysosma R. E. Woodson 7. Colpus without membrane ................ Caulophyllum Michx. 6. Pollen grains smaller (25—550)×(20—527.5) μ 7. Pollen grains prolate-perprolate .................... Leontice L. 7. Pollen grains spheroidal-prolate...Epimedium L., Podophyllum L. 1. Pollen grains tetrad ............................ Sinopodophyllum Ying     

中国北部绣线菊属的花粉形态及分类学意义

本文用光学显微镜和扫描电镜观察了中国北部绣线菊属ＳｐｉｒａｅａＬ．２１种及６个变种的花粉形态,描述了外壁纹饰的形态特征,指出了外壁纹饰特征在分类上的意义。绣线菊属的花粉为球形至长球形,外壁纹饰为条网状至条纹状。外壁纹饰类型不具有属内分组意义,但对一些种类具有一定的分类价值。花粉形态支持将曲枣绣线菊Ｓ．ｆｌｅｘｕｏｓａＦｉｓｃｈ。并入石蚕叶绣线菊Ｓ．ｃｈａｍｏｅｄｒｙｆｏｌｉａＬ．的观点［Ｍａｘｉｍｏｗｉｃｚ,Ｃ．Ｊ．（１８７９）、Ｒｅｈｄｅｒ,Ａｉ．（１９４０）］,不同意将蒙古绣线菊毛枝变种Ｓ．ｍｏｎｇｏｌｉｃａＭａｘｉｍ．ｖａｒ．ｔｏｍｅｎｔｕｌｏｓａＹｕ提升为贺兰山绣线菊Ｓ．ｔｏｍｅｎｔｕｌｏｓａ（Ｙｕ）Ｙ．Ｚ．Ｚｈａｏ［赵一之（１９８７）］。     

中国柽柳科植物花粉形态的研究

本文用光学显微镜和扫描电镜观察了分布于我国的4属30种柽柳科植物花粉形态。并用透射电镜研究了柽柳属的代表种, Tamarix elongata外壁内部的超微结构。本科花粉为三沟, 少数属种为三拟孔沟。根据扫描电镜观察, 柽柳属花粉外壁表面具粗网状纹饰和细网状纹饰, 以及界于这两个类型之间的过渡类型。水柏枝属外壁表面具粗网状纹饰, 细网状纹饰, 小穿孔以及小的蠕虫状突起。红沙属和枇杷柴属均为细网状纹饰。 本科柽柳属花粉与杨柳科中柳属的花粉特征较相似, 本文提出了它们之间的区别。     

Pollen Morphology of Polemoniaceae in Relation to Systematics and Pollination Systems: Scanning Electron Microscopy

Representative pollen grains of each genus and section of the family Polemoniaceae were examined with scanning electron microscopy. Exine pattern diversity within the family is discussed in relation to pollination biology. Pollen data support some previously recognized relationships within the family; in other instances the use of pollen morphology suggests the institution of new associations. The value of pollen morphology as an index to possible phylogenetic interpretations within the Polemoniaceae is discussed.     

紫草亚科附地菜族的花粉形态研究

本文用光学显微镜和扫描电子显微镜系统观察了附地菜族5个属26种植物花粉形态。五属是附地菜属、车前紫草属、滨紫草属、山茄子属和皿果草属。观察证明属间花粉形态有明显的差异。花粉资料为族内属的划分和皿果草属的建立提出了花粉学证据。     

SEM SURVEY OF POLLEN MORPHOLOGY AND CLASSIFICATION IN HYDROPHYLLACEAE (WATERLEAF FAMILY)

A general survey of pollen morphology in Hydrophyllaceae, using scanning electron microscopy, is presented. Hydrophyllaceous pollen grains are relatively homogeneous, tricolpate or tricolporate, and with a tectate-perforate to semitectate exine structure. Surface ornamentation is basically reticulate, but varies sufficiently from genus to genus, and sometimes from species to species, to permit interesting comparisons, but not to draw profound phylogenetic conclusions.     

Pollen morphology in Psychotria (Rubiaceae, Rubioideae, Psychotrieae) and its taxonomic significance. A preliminary survey

The pollen morphology in 168 species of Psychotria (Rubiaceae, Rubiodeae, Psychotrieae) has been investigated using light microscopy and, for 61 of the speices, scanning electron microscopy. Transmission electron microscopical studies have been carried out for seven of the species. Psychorria is very heterogeneoous pollen morphologically and pollen grain characteristics cannot be used for the delimination of the basis of aperture morphology, thickness of exine, size of lumina, muri, columellae and bacula, and sculpture. A key to the identificantion of the pollen types is presented and all types are issstrated. The pollen grains in Psychotria are usually 3–to 5colporte, 3-to 5-colpate or inapertuarate, rarely 2–4-or 5-porate, and have an exine that vanes widely in thickness. The sexine is reticulate, microreticulate, tectate-perforate, rugulate or intectate, and smooth or sculptured. Exine morphology presents important characters for the taxonomic subdivision of Psychotria . Previous intrageneric classifications are in part supported by pollen morphology, but contradictions between this and other sets of charactes, such as inflorescence features. are common.     

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.     

云南松花粉形态研究

在云南松(Pinus yunnanensis Fr.)小孢子发生发育过程中,花粉母细胞、四分孢子及花粉粒均见有粘连现象。花粉气囊的形态、大小变化复杂多样。除一般具两个正常气囊的花粉粒外,还观察到气囊不发育、具一个气囊、二个异形气囊、三个气囊和四个气囊的花粉粒。成熟花粉壁从外至内可分为外壁外层、外壁内层、内壁外层和内壁内层,它们的构成成分及形态均有明显差别。贮存后花粉的内壁结构发生了明显变化。     

Pollen morphology of Adenandra (Rutaceae: Diosminae) and its taxonomic implications

The pollen morphology of Adenandra Willd. (Rutaceae: Diosminae) was investigated to determine its taxonomic significance. Pollen of 27 of the 30 infrageneric taxa (representing 16 of the 18 species) was investigated by LM, SEM and TEM. Adenandra differs from all other Diosminae in having 4-colporate rather than 3-colporate pollen grains. This supports the alleged monophyletic status of the genus. Exine morphology and structure, however, is extremely diverse considering the size of the genus, with eight distinct pollen types and four subtypes being discerned. In some members the grains have uniform macroreticulate, striate or striato-reticulate sculpturing, whereas in others the poles have striate, striato-reticulate or reticulate-perforate sculpturing with various types of reticulate or rugulate sculpturing at the mesocolpia. Taxonomic groupings revealed by the pollen characters suggest elationships between taxa that were not previously apparent. It is suggested that evolutionary diversification among species of Adenandra is often more strikingly reflected by pollen morphology than by macromorphology, hence the eurypalynous state of the genus.     

Pseudointegricorpus clarireticulatum (Samoilovitch) Takahashi: morphology and ultrastructure

Dispersed tricolpate pollen of Pseudointegricorpus clarireticulatum (Samoil.) Takah. from the Upper Maastrichtian in Zeya-Bureya Basin, Amur (Heilongjiang) River area, Russian Far East/China has been studied with light and electron microscopy. Pollen size, pole outlines and the shape of equatorial projections show some variation within the species. The exine is striate-reticulate, semitectate and columellate. The species is characterised by highly complex structures that have harmomegathic function and include equatorial projections, endexinous thickenings, difference in the thickness of the infratectum, foot layer and endexine throughout the pollen grain, and equatorial furrows. Exine layers taper towards colpi regions while they break abruptly in furrow regions. The furrows could have helped to shed the exine quickly and enabled pollen germination. A non-extended region with a small cavity in the ectexine was observed in the equatorial region. We think that this region is characteristic of most Triprojectate species.     

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。     

Pollen and stigma morphology of some Phaseoleae species (Leguminosae) with different pollinators

Pollen transport to a receptive stigma can be facilitated through different pollinators, which submits the pollen to different selection pressures. This study aimed to associate pollen and stigma morphology with zoophily in species of the tribe Phaseoleae. Species of the genera Erythrina, Macroptilium and Mucuna with different pollinators were chosen. Pollen grains and stigmas were examined under light microscopy (anatomy), scanning electronic microscopy (surface analyses) and transmission electronic microscopy (ultrastructure). The three genera differ in terms of pollen wall ornamentation, pollen size, pollen aperture, thickness of the pollen wall, amount of pollenkitt, pollen hydration status and dominant reserves within the pollen grain, while species within each genus are very similar in most studied characteristics. Most of these features lack relationships to pollinator type, especially in Erythrina and Mucuna. Pollen reserves are discussed on a broad scale, according to the occurrence of protein in the pollen of invertebrate- or vertebrate-pollinated species. Some pollen characteristics are more associated to semi-dry stigma requirements. This apical, compact, cuticularised and secretory stigma occurs in all species investigated. We conclude that data on pollen and stigma structure should be included together with those on floral morphology and pollinator behaviour for the establishment of functional pollination classes.     

若干悬钩子属植物的花粉形态研究

蔷微科悬钩子属１０种植物的花粉形态进行了扫描电镜观察,描述了花粉形态的特征,探讨了植物花粉形态特征与外部形态特征的关系。     

东北杜鹃花属植物花粉形态的研究

利用光学显微镜和扫描电子显微镜对东北杜鹃花属(Rhododendron Linn.)6种, 1变种, 1变型的花粉形态进行了观察和比较研究。该属花粉粒均为四合花粉。四合花粉呈正四面体排列。花粉粒近球形。每粒花粉均具3沟,在四合花粉粒上,相邻花粉粒上的沟相接,有些种可见沟内的萌发孔。光镜下可见花粉外壁为内外两层,厚度约相等。不同的种在花粉粒大小上有区别。在扫描电镜下观察可见不同的种花粉表面具有不同的纹饰。即该属在花粉形态上具有种的特性。     

POLLEN MORPHOLOGY OF THE EUCHARIDEAE (AMARYLLIDACEAE)

Eucharis, Caliphruria, and Urceolina form a monophyletic group of petiolate-leaved, Neotropical Amaryllidaceae ecologically specialized to the understory of primary tropical rain forest below 2,000 m elevation. Pollen morphology of the three genera is surveyed. Pollen grains of all species of Eucharis, Caliphruria, and Urceolina are boat-shaped elliptic, monosulcate, heteropolar, and bilateral in symmetry. Exine sculpturing is semitectate-columellate and reticulate in all species examined. A transformation series in reticulum coarseness and pollen grain size is described. The large pollen grain with coarse reticulum of most Eucharis species is considered ancestral. The fine reticulation of Caliphruria is considered derived and the exine morphology of Urceolina is intermediate. Both of these genera have medium-sized pollen grains. Exine dimorphism common to all Urceolina, but rare in Eucharis and Caliphruria, may be symplesiomorphous among those taxa exhibiting this morphology. The three genera are largely uniform in pollen grain ultrastructure, with completely ektexinous exines. Pollen grain size in Eucharis is not closely correlated with style length. Several wide-ranging species show considerable intraspecific variation in pollen size. Parallelisms in pollen grain evolution among related tribes of Neotropical Amaryllidaceae are discussed.     

杉科植物花粉形态的研究

杉科(Taxodiaceac)是裸子植物的重要科之一。全科共有10属16种。本文用光学显微镜和扫描电镜观察了本科7属10种植物花粉,并用透射电镜研究了其中5个属代表种的外壁内部的超微结构。