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1.
山西霍山罂粟科植物花粉形态   总被引:3,自引:0,他引:3  
杨瑞林  魏学智  毕润成 《广西植物》2003,23(3):231-232,I003,I004
利用光学显微镜和扫描电子显微镜对山西霍山罂粟科白屈菜属白屈菜、紫堇属延胡索、角茴香属角茴香、秃疮花属秃疮花 4种的花粉形态进行了观察和比较研究 ,以上 4种花粉差异大。角茴香花粉粒近球形 ,具合沟 ;延胡索花粉粒长球形 ,表面纹饰较光滑 ;白屈菜花粉粒长球形或近球形 ;秃疮花花粉粒近球形。角茴香花粉表面纹饰为刺状纹和细网状纹的复合纹 ,白屈菜花粉表面纹饰为细网状纹和颗粒状纹的复合纹 ,秃疮花花粉表面纹饰为细颗粒状纹。延胡索、白屈菜、秃疮花花粉粒的萌发沟均为三沟 ,但沟的形态均不相同  相似文献   

2.
F. B. Sampson 《Grana》2013,52(2):61-73
Hedycarya has pollen in permanent tetrads. H. arborea, the New Zealand species, differs from others studied, in having a cap of more or less imperforate tectum at the distal pole of each grain. This polar region is not an aperture and the pollen tube emerges through a papillose part of the external wall of each grain. Transmission electron microscope studies of immature and mature tetrads reveal a most unusual exine structure. "Radial processes" develop by accumulation of sporopollenin around unit membranes of similar dimensions to the plasmalemma, and extend from just beyond the intine to the tectal region. The entire exine is considered ectexinous. During development, members of a tetrad are interconnected by cytoplasmic channels and the synchronous division into generative and vegetative nuclei within each tetrad is attributed to their presence. The channels become closed by the deposition of intine. Comparisons are made with exine structure in some other members of the woody Ranales and with some other plants with tetrad pollen.  相似文献   

3.
三种黄花石蒜植物的花粉形态比较   总被引:1,自引:0,他引:1  
利用光学显微镜和扫描电镜对三种开黄花的石蒜属(Lycoris Herb.)植物的花粉形态进行观察和比较.结果表明:三种植物花粉均为两侧对称,赤道面观呈舟形或肾形,极面观为椭圆形或长椭圆形,萌发孔类型为远极单槽,槽长几达两端;三种植物花粉外壁具网状纹饰,且在网眼底壁及网脊多附有小乳突.通过花粉特征及其他性状的比较研究,对三种黄花石蒜植物的分类鉴定和系统演化关系进行了初步探讨.  相似文献   

4.
Pollen morphology and exine structure of the seven Hymenocallis Salisb. species present in Venezuela were investigated using scanning (SEM) and transmission (TEM) electron microscopy. Pollen grains of all species are monosulcate, heteropolar, with bilateral symmetry, oblate to peroblate, heterobrochate, semitectate-columellate, possess unequal tectal surfaces, and are clavate or baculate when viewed with TEM. They present two equatorial apexes. When observed under SEM their surfaces appear as granulate; however, it is evident from TEM that they are in fact constituted by pila. All the species possess very large pollen (ranging from 64 to 85 μm and from 125 to 155 μm for polar and equatorial axes, respectively), and no relationship was evident between pollen size and chromosome number. All the taxa are also very similar in relation to their pollen outline, ornamentation and internal structure, thus indicating that the genus is accurately delimited from the palynological point of view and that discrete characteristics can only be used in some cases to delimit individual species.  相似文献   

5.
The pollen morphology of eleven (Baroniella Constantin & Galland, Baseonema Schltr. & Rendle, Camptocarpus Decne., Cryptolepis R. Br., Cryptostegia R. Br., Gonocrypta Baill., Harpanema Decne., Ischnolepis Jum. & H. Perrier, Menabea Baill., Pentopetia Decne., and Tanulepis Balf. f.) of the 13 genera of the Periplocaceae from Madagascar have been examined using light-, scanning-, and transmission electron microscopy. All of the genera are characterized by pollen grains arranged in tetrads. The arrangement of the grains may be rhomboidal, decussate or tetragonal. The 4–6 pores present are restricted to the junction area of adjacent grains. Cryptostegia differs from the other genera in that the arrangement of pollen grains is only decussate. In Menabea the tetrads are united into a pollinium. The exine is smooth and consists of a distal stratum (tectum), subtended by a granular stratum consisting of granules of unequal size. Towards the base larger granules are present. In Camptocarpus, Harpanema and Tanulepis the exine is stratified into a distal stratum (tectum), a thin granular stratum and an almost continuous basal stratum (foot layer). The inline is well developed. The pollen grains of tetrads are connected by wall bridges (cross-wall cohesion). The internal walls in Camptocarpus, Harpanema and Tanulepis differ from the other genera in the absence of a tectum. The pollen morphology of the taxa investigated is very similar and of little value for distinguishing the species and genera investigated. The distinctive difference in exine structure between the above mentioned three genera and other genera investigated emphasizes the importance of exine ultrastructure in the Periplocaceae.  相似文献   

6.
The pollen of six taxa of the genus Rubus endemic to Poland (R. capitulatus, R. chaerophylloides, R. ostroviensis, R. posnaniensis, R. seebergensis and R. spribillei)was studied using light and scanning electron microscopy. The study objective was to extend the knowledge of the species pollen morphology and to investigate whether pollen morphology may help to taxonomically distinguish a very rare bramble species. Study material was derived from six natural localities where the species occur in the Wielkopolska region (Poland). Ten quantitative pollen grain features were analysed as well as the following qualitative ones: outline, shape, type of bridge and exine sculpture. Only mature, correctly formed pollen grains (30 per specimen) were measured and 180 pollen grains were examined in total. It was found that R. capitulatus and R. seebergensis had the highest mean values of P, E and Le features. In addition, pollen grains of R. capitulatus were most flattened (mean P/E ratio equals 1.14), while those of R. seebergensis were most elongated (mean P/E ratio equals 1.27). R. spribillei was the only species with striae of similar width as muri, whereas striae in the remaining species were wider. R. chaerophylloides and R. posnaniensis were characterised by specific, similar exine sculpture. Nevertheless, it should be stated that differences between pollen features of the species studied are so small and the variability of these features are so large that it is difficult to clearly identify the species studied. Therefore, pollen grain morphology can serve only as an auxiliary feature for the determination of these species.  相似文献   

7.
为深入研究绣球属植物花粉形态的分类学价值和系统学意义,厘清绣球属与近缘属之间的系统发育关系,该文利用扫描电子显微镜(SEM,scanning electron microscope)对国产绣球属及其近缘属41种绣球花科(Hydrangeaceae)植物的花粉形态以及表面纹饰进行了观察。结果表明:绣球属及其近缘属的花粉为三孔沟;形状多数为长圆体形或近球体形;赤道面观为椭圆形或圆形;极面观多为圆形,少数为三角形或圆三角形。花粉外壁纹饰可分为网状和孔穴状。网眼内的三级纹饰可分为光滑和具颗粒状突起。根据花粉形状和外壁纹饰类型将上述物种划分为4个组,即花粉的形状为长圆体形,表面纹饰为孔穴纹饰;花粉的形状为长圆体形,表面纹饰为网状纹饰;花粉的形状为近球体形,表面纹饰为孔穴纹饰;花粉的形状为近球体形,表面纹饰为网状纹饰。以上可进一步细分为8个类型。上述表明花粉形态证据可为绣球属及其近缘属的属下分类和种间界定提供重要佐证;但结合前人的系统发育重建分析该属植物花粉形态的系统学意义相对有限,如花粉形态证据对于该属及其近缘种属系统发育树上大支的界定难以提供有力的证据。  相似文献   

8.
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.  相似文献   

9.
凤仙花属(Impatiens L.)10种植物花粉形态的扫描电镜观察   总被引:1,自引:0,他引:1  
利用扫描电镜观察了10种凤仙花属(Impatiens L.)植物的花粉形态。结果表明:本属花粉为单粒花粉,呈长圆形至长矩圆形,大小为20.3~46.7 μm,具角萌发孔,网状纹饰,网眼明显;根据花粉网状纹饰中网眼内是否具颗粒状突起可将其分为2类:(1)网眼内无或近无颗粒状突起,黄金凤(I. siculifer)和婺源凤仙花(I. wuyuanensis)的花粉纹饰属于这一类型;(2)网眼内有明显颗粒状突起,其余8个种的花粉纹饰均属于该类型。研究表明,花粉特征,特别是花粉粒网状纹饰中网眼内有无颗粒状突起及颗粒状突起的形态等特征,在凤仙花属内常具种水平上的可见变异,因而可作为种类划分的依据,它们在分类学上的价值应予以关注。  相似文献   

10.
Pollen grains ofParis, Medeola, andScoliopus have been examined with light, scanning electron, and transmission electron microscopies.P. quadrifolia L.,P. verticillata Bieb.,P. delavayi Franch. andP. polyphylla Smith have monosulcate pollen characterized by psilate, foveolate or reticulate exine sculpture. In contrast to the former species,P. japonica (Fr. et Sav.) Franch. andP. tetraphylla A. Gray have monosulcate pollen with gemmate (rarely rugulate) exine.Medeola has monosulcate pollen with reticulate exine that is distinct from that ofParis. Scoliopus has monosulcate pollen characterized by a peculiar reticulate exine pattern. The palynological evidence suggests thatParis andTrillium are closely related to each other, andMedeola andScoliopus should be separated fromParis andTrillium.  相似文献   

11.
Pollen morphology in ten plants of F2 progeny of an interspecific tree hybrid, Chorisia insignis H. B.& K.×C. speciosa St. Hil (Bombacoideae, Malvaceae) has been studied with a view to have an insight in to the effect of hybridization on the pollen morphological features in F2 generation. The study is a sequel to an earlier study on the pollen morphology of Chorisia species and their F1 hybrid, in which case the hybrid pollen uniformly exhibited the apertural features of the male parent and exine features of the female parent. In the F2 progeny the pollen grains display the apertural feature of the male parent in all the plants. However, with regard to exine ornamentation, variability has been observed. Of the ten plants, two plants exhibit the exine features of the male parent showing empty lumina (without bacula), five plants have their pollen exactly like that of the F1 plant (showing prominent columellar heads in the lumina of the apocolpium region) and the remaining three plants showing columellae in lumina of both apocolpium and mesocolpium region being different from the above types. It has been inferred that the variability in the exine pattern in F2 pollen indicates that the pollen exine pattern in hybrids, perhaps, is not unequivocally controlled by sporophytic or gametophytic genomes.  相似文献   

12.
Anton Igersheim 《Grana》2013,52(6):321-326
Pollen of 20 species of Rondeletia, covering three subgenera and seven sections or “species groups” of the genus, was studied using light and scanning microscopy. Rondeletia, characterized by binucleate mature pollen grains like numerous other Rubiaceae, was found to be eurypalynous. The pollen is isopolar and small-sized (average equatorial diameters 11.4–22.8 μm) and 3-colporate (rarely 4-colporate). In equatorial view, the pollen grains are mostly ± spheroidal (rarely suboblate); in polar view (ambitus), they are mainly circular or semiangular (intersemiangular in one species only). Three different exine types are distinguishable: exine with 1) tectum minutely perforate, perforations usually isodiametric, 2) tectum with comparatively large, not isodiametric perforations or 3) coarsely reticulate; supratectal sculpturing elements are lacking; the width of the perforations and lumina is either equal or different at the apo- and mesocolpia; in a few species rod-like luminal processes are present. Palynological features of most of the investigated taxa tend to overlap so that palynology is not very helpful in supporting the subgeneric division of Rondeletia. It was, however, noted that pollen morphology, to some extent, supports the sections of subgen. Arachnothrix. Palynologically, the subgen. Rogiera was found to be heterogeneous in that each of the three investigated species is characterized by a different exine type; one of these, R. strigosa, differs from all other Rondeletia species investigated in having a coarsely reticulate exine. R. odorata (subgen. Rondeletia) differs from all other investigated species in its intersemiangular pollen shape.  相似文献   

13.
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.  相似文献   

14.
Pollen grains of 30, mainly annual, species from 134 populations of the genus Veronica (Plantaginaceae, formerly Scrophulariaceae) from the Mediterranean Region, have been studied with light and scanning electron microscopy. Three pollen types are defined based on pollen size and exine surface sculpture. In some cases within the study group pollen size can be useful in species determination. Hypothetical relationships of pollen grain size and aperture number with ploidy level, style length and corolla diameter are discussed. The ornamentation of the exine in Veronica, although generally a conservative character within the genus, gives some additional support to the most recent infrageneric classification of Veronica.  相似文献   

15.
16.
Anther development, microsporogenesis and microgametogenesis in several species of Heliconia were investigated as part of a complementary embryological study of the Heliconiaceae. All studied Heliconia species present bithecate and tetrasporangiate anthers with fertile pollen grains; only H. rivularis, a natural hybrid, presented sterile pollen grains of variable size and no content. The anther wall has an uniseriate epidermis and endothecium, the latter with helicoidal thickenings, although some cells of the middle layers also showed thickenings; the biseriate tapetum is of amoeboid non-syncytial type, since the tapetum cells did not fuse together forming a true plasmodium. The microsporogenesis is successive leading to isobilateral tetrads. The inaperturate pollen grains had a very reduced exine consisting of a thin, more or less continuous layer with small spines upon; the pollen grain shape is variable among the species, all of them presenting heteropolar pollen, except H. angusta with isopolar ones. Most of these characteristics were shared with other studied Zingiberales, although more studies need to be done.  相似文献   

17.
The pollen morphology of Diosma and Coleonema of the taxonomically problematic subtribe Diosminae (Rutaceae) was investigated to determine its taxonomic relevance. Pollen of 26 of the 28 species of Diosma and of each of the eight species of Coleonema was investigated by LM, SEM and TEM. In pollen of Diosma the exine sculpturing is uniform, and only one pollen type, reticulate, could be distinguished. In contrast, exine sculpturing shows interspecific variation in Coleonema and three distinct types, striate, reticulate and perforate, could be discerned. Species groupings indicated by the pollen types suggest possible relationships between species within Coleonema and with other genera that were not previously apparent. Pollen data support macromorphological evidence that suggests the generic re-classification of the Diosminae.  相似文献   

18.
Studies on protoplasts isolation were carried out with mature pollen grains of 29 samples of species of Allium aflatunense, A. cepa, A. fistulosum, A. karataviense, A. longicuspis, A. nutans, A. odorum, A. sativum and A. schoenoprasum. Surface sterilized pollen grains drifted from crushed anthers were incubated in an enzyme solution containing 1% (w/v) cellulase Onozuka R-10, 1% (w/v) Macerozyme R-10, 0,5 mol l-1 sucrose and the basal salts of Nitsch medium. Protoplasts were released within 3 to 120 min, either from the pollen grain, through a slightly disturbed germination pore (narrow aperture), or through a wider aperture, when the exine surrounding the germination pore was disturbed. For the first time, protoplasts were obtained from 13 genotypes of 6 Allium species, at a rate of 1 to 30% of the digested intact pollen grains, depending on the genotype.  相似文献   

19.
中国有胡桃科( Juglandaceae)植物约7属27种1变种,南方和北方均有分布[1];该科植物通常为落叶或半常绿乔木或小乔木,大部分种类具有药用、材用和食用等价值,其中,青钱柳﹝Cyclocarya paliurus ( Batal.) Iljinsk.﹞为重要的药用植物,其叶的多糖复合物可增强糖尿病小鼠对葡萄糖的耐受力[2-3];胡桃( Juglans regia Linn.)和美国山核桃﹝Carya illinoinensis ( Wangenh.) K. Koch﹞为重要的干果和油料作物,前者也是重要的硬木产品,果皮可用于制造活性炭[4];枫杨( Pterocarya stenoptera C. DC.)是优良的家具用材,其树皮富含纤维[5]。随胡桃科应用价值的不断挖掘,人们对胡桃科植物潜在资源的研究也不断深入。  相似文献   

20.
The aim of the present study is to describe the morphology and internal wall structure of Zingiber pollen. The pollen of 18 species of Zingiber was examined by light, scanning and transmission electron microscopy. In the sections Zingiber and Dymczewiczia (Horan.) Benth. the pollen grains are spherical with cerebroid sculpturing while in the section Cryptanthium Horan. the pollen is ellipsoid with spira-striate sculpturing. All species have a thin coherent exine and an intine consisting of a thick, radially channeled outer layer and a thin, finely granular inner layer. On the basis of pollen morphology it is proposed that the section Dymczeniczia is included in the section Zingiber. The structure of the pollen wall in Zingiber resembles that of Canna and Strelitzia in having a pollen wall offering an infinite number of germination sites.  相似文献   

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