Pollen Morphology of the Family Zingiberaceae in China—Pollen Types and Their Significance in the Taxonomy

Pollen morphology of 89 species and 3 varieties belonging to 18 genera (out of 150 spcies in 20 genera) of Zingiberaceae in China was studied under both light microscope and scanning electron microscope. Pollen grains of Zingiberaceae are spherical, subspherical, ovoid and prolate, 36-225 μm in size, nonaperturate or aperturate (spiraperturate, porate). Pollen grains are almost not resistant to acetolysis. The wall is composed of a very thin exine and a thick intine. The exine is psilate, spinate, cerebelloid-areolate, striate, verrucate and foveolate. According to the presence or the absence of aperture and differential ornamentations, two types and six subtypes are recognized: I. The type Nonaperturate: (85 species and 3 varieties in 18 genera). Four subtypes can be recognized within the type based on the characteristics of the exine sculpture. These are: (1) The subtype Psilate, in which, the exine is nearly smooth (including: Hedychium, Curcuma, Kaempferia, Caulokaempferia coenobilis, Boesenbergia rotunda, Stahlianthus, Amomum compactum, Etingera, Hornstedtis, Rhynchanthus). (2) The subtype Spinate, which comprises two groups: (A) The group Short-spinate, pollen grains with smaller spines (Globba), (B) The group Long-spinate, pollen grains with longer spines (Alpinia, Amomum, Plagiostachys, Roscoea, Cautleya, Boesenbergia fallax, Caulokaempferia yunnanensis). (3) The subtype Cereblloid-areolate, pollen grains of which are spherical or subspherical, with cerebelloid sculpture (Zingiber Sect. Zingiber). (4) The subtype Striate, pollen grains of which are prolate or oliveshaped, and striate (Zingiber Setc. Cryptanthium). II. The type Aperturate, in which pollen grains are acetilysis-resistant and possess distinct apertures (mixed colpate-porate or forate), including two subtypes: (1)The subtype Mixed colpate and Porate. Pollen grains are both 3-colpate and 1-3-porate, and usually with one long spiral, two short (straight or slightly curved) colpi and 1-3-poris. The exine is verrucate or not, nearly sinuolate (Costus speciosus, C. tonkinensis, C. lacerus). (2) The subtype porate, whose grains are 6-8-porate and exine is foveolate (Costus megalobractea). The taxonomic significance of the pollen types in the family Zingiberaceae is also discussed.     

槭树科花粉形态及其系统学意义

报道了槭树科(Aceraceae)槭属21组33种和金钱槭属2种植物的花粉形态。本科花粉近球形至长球形,极面观为三裂圆形。从花粉萌发孔类型看,金钱槭属Dipteronia具三孔沟,槭属（Acer)除4组具三孔沟外,其余均为三沟。从花粉外壁纹饰看,金钱槭属2个种和槭属的大多数种为条纹状,罕为细条纹－拟网状和皱波状。通过花粉形态分析,并结合其它方向的证据,我们认为：（1）Sect.Palmata,Sect.Spicata和Sect.Microcarpa可能是槭属中与金钱槭属关系最密切的类群;（2）A.distalum和A.nipponicum代表了近缘的两个单种组;（3）A.pseudoplatanus不同于Sect.Acer的其它4个种而与A.saccharum可能存在更为密切的关系;（4）Sect.Carpinifolia(细条纹－拟网状外壁纹饰）和Sect.Negundo(皱波状外壁纹饰）则可能代表了槭属中最特化的类群;（5）按槭树科花粉三孔沟到三沟的演化规律,Dipteronia较Acer原始。     

Pollen Morphology of Dioscorea in China

This paper deals with pollen morphology of 33 species belonging to 5 sections of Dioscorea in China. They were examined under both LM and SEM. The pollen grains of Sect. Stenophora are monocolpate with the size of 17-25.5×26.8-39.1μm, the exine is reticulate, striate, parforate-reticulate or cerebro-reticulate, while those of the other sections are bicolpate, reticulate or cerebro- reticulate with the size of 19.2-26.7×13.9-23.1μm. Based on palynological data Sect. Stenophora may be considered primitive and Sect. Enantiophyllum the most advanced in Dioscorea.     

栝楼属花粉形态研究及其在分类学上的意义

本文收集了国内外栝楼属Trichosanthes 31种1变种,在光学显微镜和扫描电镜下,进行了花粉粒形态的比较观察。该属花粉粒为3孔沟型,外壁表面纹饰可分为四个类型,即：疣状或皱波状(小苞组),粗网状(大苞组),细网状或光滑(叶苞组),近光滑或皱波状(王瓜组)。这四个类型的划分与植物形态分类基本一致,可作为分组及分种的依据之一。花粉特征支持将叶苞组分为叶苞亚组和柔毛亚组,如叶苞亚组有明显的沟,而柔毛亚组没有。     

一些蔷薇属植物的花粉形态研究

本文通过对中国原产的蔷薇属植物中的6个种和3个月季品种的花粉,进行扫描电镜观察,对花粉形态进行了描述,探讨了有关植物在进化过程中的地位,及通过花粉形态来鉴定月季品种及其倍性的可能性。     

半日花花粉形态种内变异及其花粉地理研究

用扫描电镜在个体水平上研究了产自两个地区的半日花花粉,并首次发现花粉种内变异与其地理分布之间的显著相关,半日花花粉形态在种内个体之间存在差异,以餐壁纹饰明显分为穿孔型和条纹型花粉;按形状和大小又可分为近球形较小和长球形较大花粉。外壁纹饰与形状、大小所得类型基本吻合。本种花粉,因所处地理环境的不同而外壁纹饰也有明显差异,条纹型花粉分布于新疆天山地区,而穿孔型花粉出现在内蒙古伊盟桌子山,并认为花粉外壁     

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.     

Pollen Morphology of the Genus Malus and Its Taxonomic and Evolutionary Significance

The pollen morphology of 26 species and 5 hybrids of the genus Malus was investigated with aid of SEM. It is found that the pollen morphology of Malus is rather similar in shape, size, position and number of aperture and exine sculpture. The characters of polle morphology of sections and series are as follows: Sect. Malus Ser. Baccatae: Striae regular, parallel to colpi, and conjunct at pole; Ser. Pumilae: the same as in Ser. Baccatae, but more or less curved near pole. Sect. Docyniopes: Striae regular and parallel to colpi, but bent near pole. Sect. Chloromeles: Striae irregular, dense and interlock. Sect. Sorbormalus: Striae irregular, sparse and not interlock. Ser. Sieboldiance: pollen grains prolate, with perforation among striae, colpi narrow; Ser. Kansuenses: Pollen grains spheroidal, colpi wide in the middle but narrow at both ends, striae relatively dense and regular, mostly dichotomous, perforation present; Ser. Yunnanenses; Pollen grain spheroidae, colpi wide in the middle but narrow at both ends, striae obviously irregular, less dichotomous, perforation absent. The major evolutionary trend of exine sculpture of pollen may be from densely thin-striate to sparsely striate with perforation. Characters of the exine sculpture of hybrids can be used to recognize the rela-tionship between the parental species.     

湖北产八角莲属植物花粉形态研究

应用光学显微镜和电子扫描显微镜,对湖北产八角莲属４种植物八角莲、六角莲、小八角莲和乌云伞的花粉作了比较观察,找出了它们的鉴别特征,为该属的进一步研究提供依据。     

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     

Interspecific crossability studies in poplars

Summary Pollen-stigma interactions were studied with scanning electron microscopy in intraspecific and intersectional crosses of Populus tremuloides (Sect. LEUCE); P. deltoides, P. nigra (Sect. AIGEIROS); and P. trichocarpa (Sect. TACAMAHACA). Intraspecific variation in hydration, size of hydrated pollen grains, and tube morphology is described. Exine sculpture in P. tremuloides was densely spinulate or scabrate, in P. trichocarpa densely reticulate, in the other species somewhat intermediate. In six of seven intersectional cross combinations pollen-tube behavior on the stigmatic surface at 5–22 hours after pollination was the same as in conspecific matings; in P. tremuloides x P. trichocarpa crosses, the percentage of twisted and bulging tubes was significantly higher. Irradiated mentor pollen did not affect pollentube behavior of adjacent incompatible pollen, but increased hybrid seedling production in interspecific crosses. By contrast, hexane treatment of pollen or stigma, and the spraying of catkins with gibberellic acid or naphtalene acetic acid were ineffective. The results are discussed in relation to several mechanisms presumed to be involved in restricting gene exchange among poplar species; and in relation to Hogenboom's (1973) incongruity concept.     

Pollen morphology of the genus Nothofagus and its taxonomic significance

The present paper describes the pollen morphology of 26 species and 2 varieties in Nothofagus from Australia, New Zealand, New Caledonia, New Guinea and South America. Pollen grains were all examined with light microscope (LM), scanning electron microscope ( SEM ) and transmission electron microscope(TEM). A comparative analysis of pollen exine ultrastructure was made for some species. The results are summarised as follows: Pollen grains are oblate to peroblate, 5～8-short-colpate, rarely 4- or 9-colpate; colpi generally thickened at margins; pollen surface spinulose. The exine ultrastructure of Nothofagus differs considerably from that of the other genera in the Fagaceae. The pollen grains of the species examined here show great differences in shape, size, colpal number and characteristics of colpi at margins and could be divided into three distinct types, i.e. N. brassii type; N. menziesii type and N. fusca type.     

Pollen Morphology of Indian Species of Saraca L. (Leguminosae)-A Threatened and Legendary Medicinal Tree

The genus Saraca L. (Leguminosae) is a universal panacea in herbal medicine. The present study investigates the comparative pollen morphology of four species of Saraca viz. S. asoca (Roxb.) de Wilde, S. declinata (Jack) Miq., S. indica L., and S. thaipingensis Cantley ex Prain growing in India to reveal differences of their pollen structures to aid taxonomic and evolutionary values. The detailed morphology and surface structure of pollen grains were studied and described using light microscopy and scanning electron microscopy. The pollen grains of Saraca showed isopolar, para-syncolporate, tricolporate, with radially symmetric, prolate and prolate-spheroidal structure. The surface of pollen of S. indica is rugulate with large lirae but in S. declinata, the surface is micro-rugulate to vermiculate with relatively thin lirae and that of S. thaipingensis is indistinct as the psilate surface with a frequent protuberance and fewer perforations were observed along with the gemmae like structure. Exine ornamentation helped to separate S. indica and S. asoca. Exine thickness varies from 3-4 μm. Presence of protuberance and exine thickness varies among individuals of the species spread over different locations. Present work also provides a unique palynological identity and interrelationship of these four species based on cluster analysis taking 23 pollen characters with the help of statistical method like the plotting of ternary graph. Ternary plots also helped to calculate the level of plasticity of each character in the intra- and inter-specific level.     

29个蔷薇属植物的孢粉学研究

采用扫描电镜技术对蔷薇属25个种及4个月季品种的花粉形态进行观察分析,探讨单叶亚属及蔷薇亚属中的芹叶组、合柱组、桂味组、月季组及月季品种之间的亲缘关系。研究表明:(1)所有被测样品的花粉都为具三孔沟的N3P4C5型单粒花粉,形状包括近球形、长球形及超长球形,其中大部分都为极轴较长的超长球形,以小檗叶蔷薇(P/E=2.29)最长。(2)在疏花蔷薇、托木尔蔷薇以及重瓣黄刺玫中发现有花粉二型现象。(3)被测样品外壁纹饰主要包括条纹、孔穴-条纹及近孔网纹3类,条纹类型主要出现在芹叶组中,而孔穴-条纹类型则为蔷薇属植物较普遍的纹饰。(4)聚类分析表明,小檗叶蔷薇与其它种亲缘较远,被测月季品种与月季组关系较近,芹叶组与合柱组关系较近,桂味组中的弯刺蔷薇与其他蔷薇的纹饰有明显区别,被单独分开。     

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。     

Studies on the Pollen Morphology of Tribe Zizipheae of Rhamnaceae in China

Pollen morphology of Chinese 19 species representing 6 genera in the tribe Zizipheae Brongn., Rhamnaceae, was examined under light microscope and scanning electron microscope. The pollen grains oblate or suboblate, rarely subspheroidal. Polar axis 13.1-26.1μm long, equatorial axis 16.5-29.6μm long, 3-colporate, colpus generally narrow, ora lalongate, with two ends connected with the thinned part of exine, forming a H-shape. There are 4 thickenings where colpi and ora pass across, or sometimes the thickenings indistinct, forming a ring. Stratification couspicuous or inconspicuous. Ornamentation of exine obscure, rarely obscurely reticulate under light microscope, but conspicuously fine-reticulate, finely reticulate-foveolate, foveolate, striate-reticulate and shortly striate under scanning electron microscope. A key to the genera based on pollen grains is provided and the general morphology of 6 genera: Paliurus, Ziziphus, Chaydaia, Berchemia, Berchemiella and Rhamnella are described. Based on 4 thickenings and H-shape, pollen grains of the tribe Zizipheae may be divided into two groups: 1. the four thickenings rather larger and conspicuous, or stretched along the colpus in some species, H-shape distinct, e.g. in Berchemiella, Chaydaia and Rhamnella, and 2. the four thickenings smaller, sometimes forming a ring, H-shape more or less conspicuous, e.g. in Berchemia, Paliurus and Ziziphus. With respect to the concept of the genera Berchemiella and Berchemia, there were two different ideas among a number of taxonomists. H. Koidzumi, J. Ohwi and S. Kitamura place the former in Berchemia as a section, but on the contrary, T. Nakai, T. Yamazaki and K. Suessenguth consider Berchemiella and Berchemia as two separate genera. The data from pollen morphology support the latter treatment. Berchemia is closely related to Berchemiella, Chaydaia and Rhamnella in the habit and the floral morphology, but differs from the others by its disc well-developed, eularged and becoming cup-shaped in fruit. They are also different from each other in the characters of pollen grains. T. Yamazaki places the genus Chaydaia in Rhamnella as a section, but according to the pollen morphology to treat Chaydaia and Rhamnella as two independent genera woild be reasonable.     

中国贝母属花粉形态的研究

本文对分布于我国的贝母属(Fritillaria L.)27种(变种)植物的花粉形态进行了光学显微镜和扫描电镜的观察,并对本属植物花粉的形态结构、类型、演化关系以及在分类学上的意义进行了讨论。     

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.     

Pollen Morphology of Asarum in China

The present paper describes the pollen morphology of 27 species, 4 varieties and 1 form of Asarum from China. The pollen grains were all examined under light microscope and scanning electron microscope. The apertures of pollen grains of Asarum are variable and so distinct as to allow the identification of individual subgenera and species. The exine ornamentation is compound and may be divided into two types: reticulate or cerebelloid under verrucae. The pollen grains of Subgen. Asarum and Subgen. Heterotropa are distinguishable, which supports the taxonomical subdivision based on the gross morphology. The differences in the pollen morphology between A. caulescens Maxim. and A. sieboldii Miq. in China and in Japan are discussed and some comparisons in the pollenmorphology between several species similar in the gross morphology are also made.     

中国芸香科植物的花粉形态

本文用光学显微镜对我国21属52种2变种芸香科(Rutaceae)植物的花粉形态进行了详细地观察研究,其中对6属6种进行了扫描电镜观察。本科花粉具沟孔,是花粉单类型的科之一。根据萌发孔的数目和外壁纹饰特点,本文将芸香科的花粉分为具3孔沟和4-6孔沟两个花粉类型,并根据各属花粉形态特征,作出了花粉形态分属检索表。此外,本文还对花椒(Zanthoxylum L.)和Fagara两属的合并问题及花椒与吴茱萸(Evodia Scop.)两属之间的亲缘关系等问题进行了讨论。