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1.
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   

2.
The pollen morphology of 11 species (including two subspecies and two varieties) belonging to two genera (Helianthemum and Fumana) of the family Cistaceae in Egypt was studied using light and scanning electron microscopy.Pollen grains of the studied taxa were found to be radially symmetrical and tricolporate.Pollen size,shape,apertures,and exine ornamentation characteristics were valuable parameters among the studied taxa.The largest pollen size was recorded in H.salicifolium and the smallest one observed in H.kahiricum subsp,schweinfurthii.Pollen shape in the Egyptian taxa varied from (sub-)prolate to prolate spheroidal,but F.arabica is different in having sub-oblate grains.The pollen data confirm that H.lippii and H.sessiliflorum are very closely related species.Pollen sculpture was useful in distinguishing between H.vesicarium var.vesicarium and H.vesicarium var.ciliatum.Three main pollen types of exine ornamentation were recognized:retipilate; reticulate to verrucate; and striate.Based on palynological data,a key for the studied taxa is suggested.  相似文献   

3.
在扫描电镜下研究了茄科天仙子族7属及颠茄属、茄参属和枸杞属3属共10属23种植物的花粉形态学特征。结果表明:天仙子族的花粉粒形状为球形、近球形、扁球形和长球形;萌发孔类型有无萌发孔、不规则的拟孔、3沟、4沟、3~4沟、散沟和3孔沟;外壁纹饰为小刺状、瘤状、各式条纹状、条纹-穴状、条纹-网状、皱波状、细网状和网状。沟膜近光滑、具小颗粒、具小刺状突起或具瘤状突起。各属植物的花粉形态在萌发孔的有无、萌发孔的类型和外壁纹饰等方面有较大的差异,可以作为探讨属间分类和系统关系的重要依据。天仙子族植物花粉萌发孔的演化趋势为:无萌发孔→3、4沟→3孔沟。无萌发孔的山莨菪属是原始类群,三孔沟的马尿泡和天仙子等属是进化类群。还讨论了与前人研究结果不同之处和可能的原因。  相似文献   

4.
含笑属(木兰科)植物花粉形态及其系统学意义   总被引:1,自引:1,他引:1  
张新华  夏念和 《广西植物》2008,28(3):311-316
利用扫描电子显微镜对含笑属12个分类群的花粉形态进行了观察和研究。花粉粒椭圆形,两侧对称,异极,具远极单萌发沟,中等大小;形成一较为自然的分类群。虽然花粉粒的大小和表面雕纹不同种间具有一定的差异,但不足以为现有的属下分类系统提供足够的证据。  相似文献   

5.
Cornukaempferia is a recently described genus of Zingiberaceae which only occurs in Thailand as a rare genus with limited geographical distribution. Only three species have been described so far, including a recently described new species, C. larsenii. These three species are morphologically very similar and additional data on other biological aspects are useful for the elucidation of their relationship. Pollen morphology of all three species of genus Cornukaempferia has been studied by light microscopy and scanning electron microscopy. The pollen grains are monad, spherical, inaperturate. The exine sculpture is echinate with psilate between the spines for C. aurantiflora and C. longipetiolata, or echinate with regulate between the spines for C. larsenii. This obser-vation helps support the taxonomic status of C. larsenii.  相似文献   

6.
Pollen morphology of seven species in two genera in the Ruelliinae, three species in one genus in the Barlerinae and 34 species in 16 genera in the Strobilanthinae (Ruellieae, Acanthaceae), were observed under SEM. Pollen grains in Ruellieae, particularly in Strobilanthinae (including Strobilanthes s.l.) exhibit great diversity and are most eurypalynous in the family. In light of the aperture types and exine ornamentation patterns, pollen grains of the genera examined fall into three major types: 1. 3-porate pollen, which includes, (1) pollen with reticulate exine ornamentation (Pararuellia); (2) pollen with gemmate exine ornamentation (Championella); (3) pollen with echinate exine ornamentation (Paragutzlaffia, Diflugossa and Pteroptychia). 2. 3-colporate pollen or 3-colporate pollen with pseudocolpi, which includes, (1) 3-colporate pollen with reticulate exine ornamentation (Eranthemum and Barleria); (2) 3-colporate pollen with pseudocolpi and ribbed or banded, and septate exine ornamentation, the lumina rounded, finely reticulate inside and arranged in longitudinal rows (Perilepta, Pteracanthus, Goldfussia, Sympagis and some species of Strobilanthes); (3) 3-colporate pollen with ribbed or banded yet not septate exine ornamentation, the lumina neither distinctly rounded and finely reticulate inside, nor conspicuously arranged in longitudinal rows (Aechmanthera, Baphicacanthus, Semnostachya and some species of Pteracanthus); and (4) 3-colporate pollen with ribbed and finely reticulate exine ornamentation but with broader bands, each band with two ridges (Strobilanthes cycla). 3. (4-)5-colporate pollen with pseudocolpi and reticulate or ornate exine ornamentation (Adenacanthus). No distinct apertures were observed in three genera, Parachampionella, Gutzlaffia and Tarphochlamys. Pollen morphological characters in the Acanthaceae can be used not only to distinguish taxa of higher ranks (subfamily, tribe and subtribe) and elucidate their relationships, but sometimes can also be used to distinguish genera and species.  相似文献   

7.
8.
Eighty-four pollen samples were obtained for 80 taxa, of which, 13 species and one variety are from sect. Brachycalyx Sweet, 58 species and two varieties from sect. Tsutsusi Sweet, and six species from subgen. Pentanthera (G. Don) Pojarkova, respectively. Pollen morphology of all samples was observed using LM and SEM. Pollen grains are revealed to be spheroidal and tetrahedral with tricolporate apertures. Pollen sizes of subgen. Tsutsusi (Sweet) Pojarkova range from 37.67 μm to 61.06μm, and the exine sculptures are more or less compactly granulated. Pollen sizes are significantly different between sect. Brachycalyx and sect. Tsutsusi of subgen. Tsutsusi. Rhododendron tashiroi Maxim. of sect. Tsusiopsis Sleumer shows a close affinity to sect. Brachycalyx. Pollen size and exine are consistent with general morphology in differentiating species in sect. Tsutsusi. Rhododendron huadingense B. Y. Ding & Y. Y. Fang, once placed as a member of sect. Brachycalyx, should be considered as a species in subgen. Pentanthera.  相似文献   

9.
10.
国产爵床科芦莉花族植物的花粉形态   总被引:3,自引:0,他引:3  
报道了国产爵床科Acanthaceae芦莉花族Ruellieae芦莉花亚族Ruelliinae 2属7种、假杜鹃亚族Barlerinae 1属3种和马蓝亚族Strobilanthinae 16属34种植物扫描电镜下的花粉形态.芦莉花亚族的地皮消属Pararuellia和喜花草属Eranthemum的花粉均为圆球形,具3孔或3孔沟,外壁为不同的网状结构; 假杜鹃亚族的假杜鹃属Barleria的花粉为长球形,具3孔沟,外壁亦为网状结构;马蓝亚族植物(包含广义的马蓝属Strobilanthes s.l.)花粉形态多样,结构复杂.依据花粉萌发孔和外壁纹饰特征,可将马蓝亚族16属植物和上述两亚族3属植物的花粉形态归纳成3大类型: 1. 具3孔类型.其中又有(1)外壁具网状纹饰者,见于地皮消属; (2)外壁具芽胞状纹饰者,见于黄猄草属Championella; (3)外壁具刺状(棒状)纹饰者,见于南一笼鸡属Paragutzlaffia、叉花草属Diflugossa和假蓝属Pteroptychia.2. 具3孔沟及具3孔沟与假沟类型(肋条带型).其中又有(1)具3孔沟和网状纹饰者,见于喜花草属和假杜鹃属; (2)具刺状(棒状)纹饰者,见于南一笼鸡属、叉花草属和假蓝属; (3)具3孔沟与假沟,外壁纹饰具节隔、肋条带状或网状,网眼纵向排列成行,网眼内有细网纹者,见于耳叶马蓝属Perilepta、马蓝属Pteracanthus(大部分)、金足草属Goldfussia、紫云菜属Strobilanthes(部分)和合页草属Sympagis; (4)具3孔沟与假沟类型,肋条带状,但不具节隔,外壁纹饰网状,网眼不成行或不明显纵向排列,网内无细网纹者,见于尖蕊花属Aechmanthera、板蓝属Baphicacanthus、马蓝属(部分)和糯米香属Semnostachya; (5)具双脊及细网状纹饰者,见于环毛紫云菜Strobilanthes cycla.3. 具(4-)5孔沟及假沟类型(肋条带型),外壁具网状或拟网状纹饰,见于腺背蓝属Adenacanthus.另外兰嵌马蓝属Parachampionella、山一笼鸡属Gutzlaffia和肖笼鸡属Tarphochlamys的花粉有无萌发孔尚不清楚,有待进一步研究.综上所述,芦莉花族植物的花粉形态具有较高的多样性,是重要的分类性状.利用花粉形态特征能较好地区分高级分类群如亚科、族以及亚族,有时也有助于阐明类群之间的相互关系,甚至也能用于区分属、种和阐明其关系.  相似文献   

11.
系统报道了中国桑寄生科Loranthaceae33种5变种植物的花粉形态,并与澳大利亚 2属6种植物的花粉形态做了比较。通过光学显微镜和扫描电镜观察,国产桑寄生科花粉外壁 纹饰可明显分为两个类型:一种类型为刺状或条状纹饰,另一种为颗粒状纹饰,这与该科的鞘 花族和桑寄生族两个族相吻合。在鞘花族类型中,3合沟、钝刺状或条状纹饰的花粉是基本类 型,合半沟或孔沟形,刺状纹饰的花粉是较进化的类型;在桑寄生族类型中,等极、3合沟、 颗粒状纹饰的花粉是基本类型,异极、副合半沟-合半沟、3沟形和沟形-短沟形或沟孔形、粗 糙或模糊颗粒状纹饰的花粉是较进化类型。根据萌发孔和纹饰可将桑寄生族类型花粉分为3个 类群:类群I包括五蕊寄生属Dendrophtho、梨果寄生属Scurrula、钝果寄生属Taxillus和大苞 寄生属Tolypanthus;类群II仅包括离瓣寄生属Helixanthera;类群III也仅1属,桑寄生属Lor anthus。在这3个类群中,类群I属于基本的类型,属间花粉差别较小,其中梨果寄生属和钝 果寄生属花粉差别最小,显示出较近的亲缘关系;类群II和类群III皆是较进化类型。  相似文献   

12.
韩荣兰  张奠湘  郝刚 《广西植物》2003,23(4):318-320,306
首次系统地报道中国槲寄生属10种植物花粉形态。通过光学显微镜和扫描电镜观察,国产槲寄生属种类可按花粉的外壁纹饰分为两大类群,与形态上划分相一致。类群Ⅰ(8种)具不显著或近光滑的外壁纹饰,这一类型又可分为2个亚型:纹饰在花粉各个部位基本上是一致的和纹饰在赤道和极、沟两侧不一致的;类群Ⅱ(2种)外壁具显著的杆状纹饰。但花粉性状对形态上相近的种类鉴定意义不大。还讨论了槲寄生属花粉的可能的演化趋势。  相似文献   

13.
猕猴桃属花粉形态及其系统学意义   总被引:19,自引:0,他引:19  
由于天然种间杂交,猕猴桃属Actinidia Lindl.的分类存在着组间界限不清、近缘种之间很难区分的问题。本文试图通过对该属不同组、系的植物花粉及种间杂交后代花粉的扫描电镜观察,探讨该属物种的系统学关系。在扫描电镜下观察了猕猴桃属植物21种、 6变种和4个不同种间杂交F1代植株的花粉,描述了它们的花粉形态,并根据花粉形态特征建立了相应的检索表。研究结果表明:(1)猕猴桃属的花粉形状主要以长球形至近球形为主,变异较小,而花粉粒大小和外壁纹饰的种间差异较大。(2)多数迁地保护物种的花粉粒以三孔沟为主,不同于以前报道的以三拟孔沟为主,原因可能是花粉样本采集地的环境不一样,以及野外的广泛杂交造成的。(3)种间杂交后代花粉空瘪,无授粉能力,是由于所采用亲本植株染色体的倍性不同,后代不能产生正常花粉所致。(4)人工选育雄株花粉外壁纹饰较野生雄株花粉的精细,这种花粉外壁纹饰变小的特征可能有利于雌雄异株植物的授粉受精。这一现象值得进一步探讨。(5)雄株花粉大小与其雌株果实大小之间有一定相关性,这一现象有助于杂交后代的早期筛选。  相似文献   

14.
中国柽柳科(Tamaricaceae)花粉形态研究及其分类意义的探讨   总被引:15,自引:2,他引:15  
研究观察了中国柽柳科(Tamaricaceae)4属27种植物的花粉形态。中国柽柳科植物花粉为三沟类型,无三拟孔沟类型,形态及外壁雕纹属间差异明显。根据花粉资料,探讨了属间的进化关系和分类地位及本科植物花粉外壁的演化途径。  相似文献   

15.
In order to provide new insights into phylogenetic relationships among the neotropical taxa of Phyllanthus , 28 illustrations are provided of the pollen grains of 22 selected species studied from 11 sections of the subgenera represented in the neotropics. Special attention has been given to subgenus Conami because of its variability in pollen morphology: of eight species illustrated, the apertures are diploporate colpi in three species and pores in five species; exine ornamentation is vermiculate in two species and pilate in the other six species. The six species in the neotropical sections Pityrocladus and Microglochidion (subgenus Emblica ) are characterized by prolate grains with an increased number of colpi (4–8). Of particular interest are species in which the pollen exine is clypeate (with exine shields); clypeate pollen grains are illustrated in two species of subgenus Xylophylla and in one species of section Cyclanthera that has unique exine shields with single central pila. The pollen of the one Brazilian phylloclade-bearing species illustrated (in section Choretropsis ) has 3-colporate grains with reticulate exine, typical for subgenus Phyllanthus , and very different from the clypeate grains of the West Indian phylloclade-bearing species in section Xylophylla . This pollen evidence clearly demonstrates homoplasy in the origin of phylloclades in Phyllanthus . Pollen morphological data suggest that the neotropical taxa of Phyllanthus have arisen following colonization from Africa (subgenus Kirganelia ) and Asia (subgenus Emblica ). © 2002 The Linnean Society of London, Botanical Journal of the Linnean Society , 2002, 138 , 325–338.  相似文献   

16.
用扫描电子显微镜对国产 1 4种蜘蛛抱蛋属植物的花粉形态进行了观察 ,该属植物的花粉形态有长球形和球形 2种 ;外壁纹饰可分为 3大类型 :( 1 )皱波状纹饰 ;( 2 )小芽孢状纹饰 ;( 3)瘤棒状纹饰。它们的演化趋势是 :皱波状纹饰→芽孢状纹饰→瘤棒状纹饰  相似文献   

17.
谭莎  查钱慧  黄永芳  洪文泓  薛克娜 《广西植物》2016,36(12):1422-1425
金花茶分类系统尚未完善,金花茶又极具观赏价值,潜在价值极高,该研究应用扫描电镜观察三种金花茶花粉形态,即平果金花茶、直脉金花茶、金花茶,并运用数理统计和图片分析的方法对其花粉形态进行了探讨.结果表明:三种金花茶花粉均属于大花粉粒,花粉平均极轴在50μm以上,花粉极面观为钝凹三角形,萌发孔为三孔沟,即N3P4C5类型.平果金花茶与直脉金花茶花粉外壁纹饰为拟网状纹饰,平果金花茶网眼较密,网脊稍不平,直脉金花茶网脊稍隆起;金花茶为蠕虫状纹饰,短条状突起.花粉形态对其分类有重要意义,通过花粉外壁纹饰的类型可知金花茶与其二者亲缘关系较远,花粉形态各指标具有种间变异性,种内具有保守性,而平果金花茶和直脉金花茶花粉外壁纹饰相同但具体分类还需进一步研究.该研究结果为金花茶种质资源分类和利用提供了参考,在一定程度上促进了金花茶资源的开发和利用.  相似文献   

18.
Astragalus is with nearly 3000 described species the largest genus of flowering plants. So far analyses of pollen characters have only been conducted for a few species of the groups within the genus. Here we analyse pollen grains of 22 species representative for Astragalus section Hymenostegis using scanning electron microscopy. We found the basic shape of the pollen grains to be oblate-spheroidal and apertures to be tricolpate as for other eudicots. The sculpturing pattern of the exine is micro-reticulate. Pollen grains show low morphological variation among different species of this section, but differences occur between sections of the genus. We conclude that the vast morphological differentiation that occurred during the rapid radiation of section Hymenostegis was not accompanied by comparable differentiation in pollen morphology.  相似文献   

19.
中国栎属植物花粉形态及其系统学意义   总被引:5,自引:0,他引:5  
曹明  周浙昆 《广西植物》2002,22(1):14-18
从系统学分类学的角度出发 ,对国产栎属 31个种的花粉进行了光学显微镜和扫描电镜观察。研究结果表明栎属的花粉萌发孔对该属的系统与分类无太大的参考价值 ;但栎属的花粉纹饰有颗粒状、聚颗粒状两种主要类型 ,具有重要的系统学分类学价值。花粉形态的研究结果支持将栎属植物划分为常绿类与落叶类的观点 ;栎属巴东栎组植物的花粉纹饰在种间存在分化 ,花粉形态的研究结果支持将巴东栎组至少划分为两个不同类群的观点 ;在佐以其他证据的情况下 ,栎属植物的花粉纹饰还具有重要的分类学价值  相似文献   

20.
Marta A. Caccavari 《Grana》2013,52(3):130-141
A survey of the pollen morphology of the American taxa of the Piptadenia -group (Mimoseae) was done including all together 384 species of the following genera: Piptadenia , Parapiptadenia , Pseudopiptadenia , Piptadeniopsis , Microlobius (= Goldmania ), Stryphnodendron , Adenopodia , Anadenanthera and Mimosa . Because of a high morphological and structural variation the definition and characterization of pollen types turned out to be very difficult. Nevertheless the presence and durability of some pollen characters allow a provisional grouping: (1) always tetrads or polyads, (2) small size 6 (20) 40 mum, (3) unstable shape but currently ovoidal and, if biconvex, ellipsoidal in the outline, (4) number of pollen grains of the polyads very variable and unstable; the most frequent numbers are 8-12-16, (5) pollen grains irregularly united in polyads, with homomorphous exine and, (6) pores always located in the angles of the pollen grains in distal-subdistal position, rarely subdistal, (7) without or with pseudocolpi or subpseudocolpi (never colpi) in the distal face, (8) endexine forming an annulus around the endoaperture with ends of free lamellae with a central white line, (9) the tectal stratum above the pores forming a small vestibular space (except in Anadenanthera ). These palynological characters or most of them confirm the affinity among genera in the Piptadenia -group and its distinction from other taxa of the subfamily Misosoideae with tetrads or polyads.  相似文献   

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