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1.
 选择中国复序苔草亚属6组4亚组的代表植物14种,进行了叶片解剖学研究,观察了其横切面 和表皮特征,证明上述特征在各类群之间存在差异,具有一定的系统学意义。这14种植物叶片的横切 面和表皮都具有一些原始的性状,表明复序苔草亚属中的植物可能在苔草属中是较原始的。在所观察 的植物中,Sect.Polystachyae植物叶片解剖学特征比较一致,说明此组的建立比较合理;而Sect.Indicae 组已有明显分化,尤其是Carex scaposa C.B.Clarke和C.densifimbriata Tang et S.Y.Liang 与其它植物明显不同,而且其外部形态特征在复序苔草亚属中也比较独特,因此赞成将它们及其近缘类群做为一个组而非亚组。  相似文献   

2.
In this paper the classification of the genus  Bergenia Moench is  provided, its geographic distribution analysed, and the phylogeny also traced.   Based  on an analysis of morphological characters such as leaves, ocreas, branches of inflorescences, Pedicels, hypan- thium, sepals, and glandular indumentum, thi genus is divided into 3 sections: 1. Sect. Scopu- losae J. T. Pan, sect. nov., 2. Sect. Bergnia, 3. Sect. Ciliatae (A. Boriss.) J. T. Pan, stat. nov. The Sect. Scopulosae J. T. Pan may be considered as the primitive one, while Sect. Ciliatae (A. Boriss.) J. T. Pan may be regarded as the advanced one, with Sect. Bergenia in between.         So far, the genus Bergenia Moench comprises 9 species in the total.  Southeast Asia and North Asia (south and east Siberia, USSR) each have only 1 species, West Asia (Afghanis- tan) has 2, Central Asia (Kirghizia-Tajikistan-Uzbekstan area, USSR) 3, South Asia 4 (Nepal has 4, India, Pakistan and Kashmir area each has 3, Bhutan and Sikkim each has 2), East Asia 6.  In East Asia, Mongolia and Korea each have only 1 species, but China has 6 (includ- ing endemic species 2 and new species 1).  Sichuan Province and Xizang Autonomous Region each have 3, Yunnan Province 2, Shaanxi Province (Qinling Mountains) and Uygur Autono- mous Region of Xinjiang each have only 1.        Thus the distribution centre of this genus  should be in the region covering Si- chuan, Yunnan and Xizang. Moreover, it is noteworthy  that Bergenia scopulosa T. P. Wang in Sect. Scopulosae seems to have retained primitive characters,  for exa- mple, non-ciliate leaves and ocreas, glabrous pedicels, hypanthium and  sepals,  and this primitive species is found in Qinling Mountains and Sichuan.  According to the distribution of the primitive species, the author suggests that the centre of origin of  this genus be in the region covering Qinling Mountains and Sichuan.  相似文献   

3.
 This paper deals with morphological characters in seedlings and adult plants of 5 species of Chinese Calycanthaceae.  The germination of seeds, morphology of cotyledons, hypocotyl and primary leaves of these species are enumerated, for example, the Chimon- anthus campanulatus, sp. nov. is characterized by half-hypogaeous and tetragonal coty- ledons, whereas other species epigaeous; the cotyledons of Calycanthus  chinensis  is obtriangular, Chimonanthus praecox, Ch. salicifolius and Ch. nitens are reniform.  On the morphological characters of these adult plants and geographical distribution of 4 species of Chimonanthus are keyed.  In addition a new species, Chimonanthus campa- nulatus, is described and it represents a more primitive type of the genus.    相似文献   

4.
    本文分析溲疏属的重要形态特征的演化趋势,讨论亲缘属的系统位置和地理分布及区系特点,分类系统的修订和补充,并编写了分种检索表。认为雄蕊不定数,花瓣覆瓦状排列,花丝无齿,子房半下位的是属于原始性状,而雄蕊定数,花瓣镊合状排列,花丝具齿,子房下位的是进化性状,因此新溲疏组应包括在溲疏属内,该组与中间溲疏组是原始类群,而溲疏组是进化类群。国产52种被分为2组,4亚组和17系。溲疏属基本上是属于北温带分布类型,而我国的横断山脉至秦岭南部和华中一带为本属的现代分布和分化中心。  相似文献   

5.
本文对蓝钟花属Cyananthus及整个狭义的桔梗科Campanulaceae(s.str.)的花粉、   染色体和形态性状作了深入的系统研究,表明蓝钟花属是该科的最原始类群,它的亲缘属有党   参属Codonopsis和细钟花属Leptocodon。  对蓝钟花属中各个种及它的亲缘属的地理分布分   析,揭示了该属是典型的中国-喜马拉雅区系的成分,横断山地区是该属的频度和多样性中心;   认为中国西南部及其邻近地区至少是桔梗科原始属的保留中心,甚至可能是该科的起源中心。   作者最后对蓝钟花属各个种的性状作了生物统计分析,在此基础上对全属进行了全面的分类   修订,把原有的26个种9个变种归并为19种(包括2亚种);对该属的次级分类也作了修订。   首次报道了该属的染色体数目和细钟花属的花粉形态。  相似文献   

6.
The genus Cephalotaxus contains a small number of species. It is adequately appreciated as a newly discovered cancerresistant medicament for the alkaloids obtai- ned from its branches leaves and barks are of curative effect.      This paper deals with the classificatory revision based on the morphological featu- res,  with the reference to the anatomical characters of leaves,  types of alkaloids and pollen morphology observed.  Two new combinations are proposed,  and 4 species and varieties are reduced in the paper. The genus Cephalotaxus is thus suggested to consist of 2 sections and 9 species.  The trees occur in East Asia and the north of Indo-China, with 88% found in China where is the distribution centre and refuge of the genus. The genus in discussion is of unique morphological features which are distinctly dif- ferent from these of Amentotaxus,  Cephalotaxaceae,  containing a single genus of Ce- phalotaxus,  is closely related to Taxaceae,  and therefore the Cephalotaxaceae is best placed in the Taxinieae of Coniferales.  相似文献   

7.
金缕梅科(广义)的叶表皮特征   总被引:7,自引:0,他引:7  
本文次氯酸钠及铬酸-硝酸离析法,在光学显微镜下,观察了19属37种(分属六个亚科)共50个样品的成熟叶表皮细胞及气孔器的特征,发现金缕梅科植物叶上下表皮细胞形状(表面观)为多边形和不规则形,垂周壁式样有平直、弓形和有波纹;气孔器仅在下表皮存在,其类型有环列型、冠列型,平列型和无规则型(图1)几种。在扫描电镜下观察了19属35种(分属六个亚科)的叶下表皮的角质膜和蜡质纹饰、气孔的形状、气孔外拱盖及拱盖内缘的特征。这些特征在亚科或属级水平上较为稳定,但有的也表现出种间差异,有一定的分类学价值。  相似文献   

8.
本文运用Wagner平面分异法(Wagner Groundplan Divergence Method),对中国东北 泥炭藓植物14个种和1变种进行了种系发生的探讨。根据所选出的21个泥炭藓不同部位的 形态学和解剖学的性状特征,将其同已知的姐妹群或其它邻近群的同源特征系列中的相应性 状做比较并遵从物种的个体发育顺序、类群趋向等标准,确定性状梯度极向,即找出祖征和衍 征,以期较系统地、定量地描述泥炭藓属种系发生过程。研究结果表明,在泥炭藓的14种和1变种中,Sphagnum magellanicum 最为原始,S. girgensohnii 和S.fimbriatum 最为进化。  相似文献   

9.
中国珍珠菜属植物的分类与分布   总被引:1,自引:0,他引:1  
  相似文献   

10.
Shibataea Makino is a genus of Subfam. Bambusoideae, with 8 species, distributed in Southeast China and Southwest Japan.  In China wild plants of the genus are found in Fujian, Jiangxi, Zhejiang, Jiangsu and Anhui provinces, especially in Fujian and Zhejiang. The genus is also cultivated in parks of Guangzhou, Teibei and some other gardens.      Raches of inflorescences in genera Semiarundinaria, Brachystachyum, Phyllostachys and Shibataea have many branches, even secondary branches.  A large bract is often present at the base of each branch, and a prophyll in the axil of the bract in Tribe Shibataeeae Nakai.  Mo- reover, an inflorescence is composed of numerous dense spikelets.  This type of inflorescence may be considered primitive.   The genera Indosasa and Sinobambusa are of more stamens (6 in the former and 3 or 4, 5 in the latter) than in the genera Semiarundinaria and Brachysta- chyum (only 3), and their inflorescences are very simple with fewer spikelets and raches,without the large bract.  This type of inflorescence may be considered more advanced.  相似文献   

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