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1.
本文对我国原始木本被子植物木兰科中的木兰属Magnolia、木莲属Manglietia、含笑属Michelia、
合果木属Paramichelia、观光木属Tsoongioderdron、拟单性木兰属Parakmeria、鹅掌楸属Liriodendron、
华盖木属Manglietiastrum 8属代表种的核型进行了研究。各属代表种的核型公式如下:夜合Magnolia
coco 32m+4sm+2st(2SAT);灰木莲Manglieatia glauca 32m+4sm+2st(2SAT);合果木Paramichelia
baillonii 34m(2SAT)+2sm+2st(2SAT);观光木Tsoongiodendron odorum 32m+6sn(2SAT);拟单性木
兰Parakmeria omeiensis 56m+16sm+4st(2SAT);鹅掌楸Liriodendron chinense 32+4sm(2SAT)+2st
(2SAT);华盖木Manglietiastrum sinicum 28m+4sm+6st(6SAT);白兰 Michelia alba 34m+4sm(2SAT)。作者对木兰科核型进化问题进行了讨论。 相似文献
2.
通过光学显微镜和扫描电子显微镜对黄精族trib．Polygonateae 7属79种以及相关类群12属15种
的叶下表皮形态及种皮微形态进行了观察。结果表明广义黄精族植物的叶表皮形态和种皮形态可分别
分为4种类型和6种类型。在黄精族中,鹿药属Smilacina和黄精属Polygonatum的叶表皮和种皮特征在
属内表现出一定的多样性,据此可将黄精属植物分为两类：第一类多表现为叶表皮细胞形状不规则,其垂周壁为波曲形或无皱褶但弯曲,种皮表面浅穴状;另一类叶表皮细胞形状为长方形或菱形,其垂周壁
直或无皱褶但弯曲,种皮表面具脊状突起或网状结构。其中,叶表皮细胞垂周壁无皱褶但弯曲为过渡
类型,在两类植物中均有表现。本研究结果还显示出竹根七属Disporopsis和黄精属的互叶类以及鹿药属
同具有波状垂周壁的叶表皮细胞和穴型种皮。舞鹤草属Maianthemum和鹿药属的S．stellata,S．trifolia
等的种皮特征相似。万寿竹属Disporum的叶表皮特征在属内表现得相当一致,但种皮特征在东亚分布
的种和北美分布的种之间区别明显。扭柄花属Streptopus叶表皮和种皮特征在属内没有分化。卵叶扭
柄花S．ovalis的叶表皮和种皮特征与属内其它种之间没有区别,确证了它在本属中的位置。扭柄花属、
万寿竹属、七筋菇属Clintonia与黄精族其它类群差别较大,但前两者与Uvulariaceae科的油点草属Tricyr-
tis和细钟花属Uvudaria较为接近,从而支持了Dahlgren将其移至Uvulariaceae的观点。而在与外类群的关系中,铃兰族的铃兰属Convallaria与黄精族具相近的叶表皮和种皮特征。 相似文献
3.
本文首次记载了对分布于峨眉山的凤仙花属Impatiens 12种植物的种子表面显微结构的观察，
并分析了种子表面形态在该属种水平上的分类价值及可能的系统学意义。种皮表层细胞特化、排列方
式、隆起状态、种脊上近合点端的突起、种子末端附属物的有无及其形态等性状被视为凤仙花属种子表
面的主要特征。依据这些性状12种凤仙花种子形态分为两种类型：1．种子表面光滑，无明显大、小细胞
分化。如白花凤仙I．wilsoni可能具3沟花粉凤仙花的种子形态的特点。2．表面粗糙，有明显大、小细
胞的分化及不同程度的细胞隆起，并呈现出多种特异形态．这代表了以一年生草本，4沟花粉为特点的
凤仙花种子形态特征。种子特征与植物体习性、花形态及花粉形态相关，在一定程度上反映了属内类群的分化，因而在凤仙花科、属的分类和系统研究中是不可忽视的性状。 相似文献
4.
利用组织透明法、石蜡切片法及薄切片法对木兰科10属82种1亚种植物叶片的结构和油细胞的
分布密度、结构及其在叶肉中的分布进行了比较研究。鹅掌楸亚科和木兰亚科在叶结构上的主要区别是：鹅掌楸亚科两种植物叶的部分下表皮细胞乳突状,且整个细胞外壁只形成一个乳突,而在木兰亚科植物中有单列多细胞或单细胞的表皮毛,却未发现乳突;鹅掌楸亚科植物叶主脉维管组织环分隔呈束状,且其外包被的纤维也排列成束状,而木兰亚科的80种1亚种植物中,叶主脉维管组织连成轮状,其外面也由一圈连续的纤维环所包围。从而支持木兰科中木兰亚科和鹅掌楸亚科两个亚科的划分。并且,从叶主脉的演化趋势来看,鹅掌楸亚科较木兰亚科进化。另外,木莲属植物叶片的结构与木兰属具有明显差异,因而进一步证明木莲属是不同于木兰属的一个独立的属。油细胞是木兰科植物叶片解剖的显著特征,在叶肉中的分布可划分为3种类型：(A)主要分布于栅栏组织;(B)主要分布于海绵组织;(c)均匀散布于整个叶肉中。油细胞的大小及其在叶中的分布与叶厚、栅栏组织层数、栅栏组织与海绵组织厚度间的比值以及下皮层的有无、表皮毛的类型、叶脉的结构等特征相结合,可作为属、甚至种的鉴别特征。 相似文献
5.
对木兰科Magnoliaceae 13个分类群的染色体进行了计数, 其中落叶木莲Manglietia decidua、香港木兰Magnolia championii、馨香玉兰Magnolia odoratissima、香木兰Magnolia guangnanensis等12个种的染色体数目为首次报道。同时对木兰科属内属间的12个人工杂交组合的后代进行了染色体鉴定,其中,二乔玉兰红元宝Magnolia×soulangeana“Hongyuanbao” (♀,2n=4x=76)与云南含笑Michelia yunnanensis (♂,2n=2x=38)、红元宝与金叶含笑Michelia foveolata(♂,2n=2x=38)杂交后代的染色体为2n=3x=57,为其亲本染色体半数之和,证明这两个远缘杂交后代为真实杂种。 相似文献
6.
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
7.
鲁迎青 《中国科学院研究生院学报》1991,29(4):352-357
本文作者首次观察了峨眉山凤仙花属Impatiens 13个野生种的花粉形态，发现3沟和4沟类型
花粉均出现在这一地区。其中3沟花粉与同科另一属水角属Hydrocera的花粉十分相似。同时注意到
花粉形态与其花的形态在某些方面具相关性，结合地理分布和生长习性等特性，得出以下结论：1．凤仙
花属3沟型花粉所指示的植物类群为一自然类群，并与水角属具有较密切的亲缘关系；2．凤仙花属4沟型花粉常具种水平上的差异，对属内类群划分具有系统学意义。 相似文献
8.
通过扫描电镜对国产水鳖科植物(包括6属13种)的种皮微形态特征进行观察，并作了系统描述。根据种皮细胞形态、外种皮表面纹饰和内种皮内层小瘤状突起的特点将水鳖科植物的种皮微形态特征划分为3种类型，即海菜花型(海菜花属)、水鳖型(水鳖属)和苦草型(苦草属、水筛属、虾子草属和黑藻属)，并作出了分属检索表。本文结果表明，种皮微形态特征可作为该科族、属以及属内种级水平分类的依据，对探讨属间关系和该科的系统发育关系亦具有重要的价值。种皮微形态特征支持Hutchinson(1959)和Eckhardt(1964)将海菜花属和水鳖属分别作为一个独立的族处理的观点。苦草属、水筛属和虾子草属种皮微形态特征的高度相似性表明它们间有密切的联系，不支持将它们置于不同亚科和族的分类处理。黑藻属虽与上述3属近缘，但其外种皮特征则较为独特，因此与水筛属放在不同族中更为合理。本文种皮微形态特征的研究结果支持iki1937)和Shaffer-Fehre(1991b)等关于水鳖科与茨藻科近缘的观点。 相似文献
9.
木通科、大血藤科种子的研究，(1)种皮的扫描电镜观察 总被引：1，自引：0，他引：1
利用种皮扫描特征进行分类学和系统演化研究，这在木通科，大血藤科研究中尚属 空白。本文就5属15种木通科植物及大血藤科植物的种皮进行了扫描电镜观察。 从种皮雕纹类型看，大血藤科与木通科存在很大差异。Akebia，Holboellia，Stauntonia属植物通常具条纹状种皮雕纹，Sinofranchetia属植物也具条纹状种皮雕纹，但其条纹上具众多疣状凸起， 在 形态上较特殊。Decaisnea属植物的种皮具嵌合型雕纹，这在木通科十分罕见。以上，进一步印证了Stapf等人关于大血藤科分类学处理的正确性，说明了Decaisnea属和Sinofranchetia属在木通科的孤立地位；以及Akebia，Holboellia，Stauntonia属之间较密切的亲缘关系。 相似文献
10.
利用扫描电镜对天南星科Araceae22属28种(除Arum maculatum产自德国外，其余均产自中国)
及菖蒲科Acoraceae 1属2种植物的花粉形态进行了观察。结果显示天南星科花粉形态在科内变异很
大。花粉粒形状从球形、近球形、椭球形到扁球形和橄榄形；萌发孔类型有散孔型、具薄壁区型、环沟型
或无萌发孔；外壁纹饰为小穴状、网状、肋条状、条纹状、疣状、具刺或光滑。主要依据花粉形态方面的证
据探讨了崖角藤属Rhaphidophora、麒麟叶属Epipremnam 、龟背竹属Monstera 3属的属间关系以及犁头尖属Typhonium属下分类中存在的一些问题。 相似文献
11.
木兰科分类系统的初步研究 总被引：10，自引：0，他引：10
刘玉壶 《中国科学院研究生院学报》1984,22(2):89-109
A new system of classification of Magnoliaceae proposed. This paper deals mainly with taxonomy and phytogeography of the family Magnoliaceae on the basis of external morphology, wood anatomy and palynology. Different authors have had different ideas about the delimitation of genera of this family, their controversy being carried on through more than one hundred years (Table I). Since I have been engaged
in the work of the Flora Reipublicae Popularis Sinicae, I have accumulated a considerable amount of information and material and have investigated the living plants at their natural localities, which enable me to find out the evolutionary tendencies and primitive morphological characters of various genera of the family. According to the evolutionary tendencies of the characters and the geographical distribution of this family I propose a
new system by dividing it into two subfamilies, Magnolioideae and Liriodendroideae Law (1979), two tribes, Magnolieae and Michelieae Law, four subtribes, Manglietiinae Law, Magnoliinae, Elmerrilliinae Law and Micheliinae, and fifteen genera (Fig. 1 ), a system which is different from those by J. D. Dandy (1964-1974) and the other authors.
The recent distribution and possible survival centre of Magnoliaceae. The members of Magnoliaceae are distributed chiefly in temperate and tropical zones of the Northern Hemisphere, ——Southeast Asia and southeast North America, but a few genera and species also occur in the Malay Archipelago and Brazil of the Southern Hemisphere. Forty species of 4 genera occur in America, among which one genus (Dugendiodendron) is endemic to the continent, while about 200 species of 14 genera occur in Southeast Asia, of which 12 genera are endemic. In China there are about 110 species of 11 genera which mostly occur in Guangxi, Guangdong and Yunnan; 58 species and more than 9 genera occur in the mountainous districts of Yunnan. Moreover, one genus
(Manglietiastrum Law, 1979) and 19 species are endemic to this region. The family in discussion is much limited to or interruptedly distributed in the mountainous regions of Guangxi, Guangdong and Yunnan. The regions are found to have a great abundance of species, and the members of the relatively primitive taxa are also much more there than in the other regions of the world.
The major genera, Manglietia, Magnolia and Michelia, possess 160 out of a total of 240 species in the whole family. Talauma has 40 species, while the other eleven genera each contain only 2 to 7 species, even with one monotypic genus. These three major genera are sufficient for indicating the evolutionary tendency and geographical distribution of Magnoliaceae. It is worthwhile discussing their morphological characters and
distributional patterns as follows:
The members of Manglietia are all evergreen trees, with flowers terminal, anthers dehiscing introrsely, filaments very short and flat, ovules 4 or more per carpel. This is considered as the most primitive genus in subtribe Manglietiinae. Eighteen out of a total of 35 species of the genus are distributed in the western, southwest to southeast Yunnan. Very primitive species, such as Manglietia hookeri, M. insignis and M. mega-
phylla, M. grandis, also occur in this region. They are distributed from Yunnan eastwards to Zhejiang and Fujian through central China, south China, with only one species (Manglietia microtricha) of the genus westwards to Xizang. There are several species distributing southwards from northeast India to the Malay Archipelago (Fig. 7).
The members of Magnolia are evergreen and deciduous trees or shrubs, with flowers terminal, anthers dehiscing introrsely or laterally, ovules 2 per carpel, stipule adnate to the petiole. The genus Magnolia is the most primitive in the subtribe Magnoliinae and is the largest genus of the family Magnoliaceae. Its deciduous species are distributed from Yunnan north-eastwards to Korea and Japan (Kurile N. 46’) through Central
China, North China and westwards to Burma, the eastern Himalayas and northeast
India. The evergreen species are distributed from northeast Yunnan (China) to the
Malay Archipelago. In China there are 23 species, of which 15 seem to be very primi-
tive, e.g. Magnolia henryi, M. delavayi, M. officinalis and M. rostrata, which occur in
Guangxi, Guangdong and Yunnan.
The members of Michelia are evergreen trees or shrubs, with flowers axillary, an-
thers dehiscing laterally or sublaterally, gynoecium stipitate, carpels numerous or few.
Michelia is considered to be the most primitive in the subtribe Micheliinae, and is to
the second largest genus of the family. About 23 out of a total of 50 species of this
genus are very primitive, e.g. Michelia sphaerantha, M. lacei, M. champaca, and M.
flavidiflora, which occur in Guangdong, Guangxi and Yunnan (the distributional center
of the family under discussion) and extend eastwards to Taiwan of China, southern
Japan through central China, southwards to the Malay Archipelago through Indo-China.
westwards to Xizang of China, and south-westwards to India and Sri Lanka (Fig. 7).
The members of Magnoliaceae are concentrated in Guangxi, Guangdong and Yunnan
and radiate from there. The farther away from the centre, the less members we are
able to find, but the more advanced they are in morphology. In this old geographical
centre there are more primitive species, more endemics and more monotypic genera.
Thus it is reasonable to assume that the region of Guangxi, Guangdong and Yunnan,
China, is not only the centre of recent distribution, but also the chief survival centreof Magnoliaceae in the world. 相似文献
12.
采用光学显微镜和扫描电镜对中国蓼属叉分蓼组20种3变种的花粉形态进行了观察和研究。结果表明其花粉形态大多数为近球形至近长球形，少数为扁球形或长球形；花粉大小为20.4～44.0µm×17.0～34.0µm：从萌发孔看，有3沟、3 孔沟、多沟、散沟；外壁纹饰为微刺—穴状、刺状、粗网状、皱块状。据此，该组花粉可划分为5种类型，即叉分蓼型(Aconogonon-type)、钟花蓼型(Campanulatum-type)、大连线冰岛蓼型(Forrestii-type)、西伯利亚蓼(Sibiricum-type)及多穗蓼型(Polystachyum-type)，编制了这些花粉类型检索表。叉分蓼型花粉的主要特征是具3沟，外壁纹饰为微刺-穴状，此种类型的植物有14种2变种。钟花蓼型花粉的主要特征是具6散沟，外壁纹饰为微刺-穴状，此种类型的植物有钟花蓼和绒毛钟花蓼。西伯利亚蓼型花粉的主要特征是具3孔沟，外壁纹饰为皱块状，此种类型的植物有西伯利亚蓼。多穗蓼型花粉的主要特征是具6(~8)多沟，外壁纹饰为粗网状，此种类型的植物有松林蓼及多穗蓼。大连线冰岛蓼型花粉的主要特征是具散沟，外壁纹饰为显著的长刺状，此种类型的植物有大铜钱叶蓼及铜钱叶蓼，结果表明叉分蓼组的花粉形态具有重要的分类学意义，研究结果支持将叉分蓼组上升为属的等级，也支持Knorringia的属的地位，大铜钱叶蓼和铜钱叶蓼应移入Koenigia属中，而松林蓼和多穗蓼仍保留在蓼属中。 相似文献
13.
本文对分布于我国的椴树科(Tiliaceae)9属44种植物的花粉形态进行了光学显微镜
的系统观察，并对其中10种花粉的外壁细微结构进行了扫描电镜观察。本科花粉为长球形、
扁球形和球形，萌发孔为长3孔沟、短3孔沟和3(一4)孔三种类型，外壁主要为网状纹饰，个 别属为刺状纹饰。根据花粉资料，本文还探讨了该科植物分类中的某些问题。 相似文献
14.
本文对中国乌头属Aconitum三亚属53种及变种的药用植物进行了比较解剖学的研究。纳出该属植物根部组织构造的6大类型和18种亚型，找出了鉴定乌头类药材的解剖学特征。并结合植物分类学。化学分类学、细胞染色体和毒性，探讨了该属组织构造与植物系统演化之间的相关性。结果表明根部具有较进化的I型和II型构造的植物，含毒性很大的双酯型生物碱，主要存在于乌头亚属乌头组3，5-11系中；较原始的Ⅲ型、Ⅳ型及少数小根类Ⅱ型构造的植物，含毒性较小的阿替生和胺醇类生物碱，主要存在于露蕊乌头亚属和乌头亚属乌头组1—2系；更原始的V型和Ⅵ型构造的植物，含毒性更小的牛扁碱型生物碱，主要存在于牛扁亚属中。本文还从解剖学的角度对乌头属下等级的系统位置作了讨沦。 相似文献
15.
利用扫描电镜对国产中国蕨科Sinopteridaceae植物9属61种6变种的孢子进行了观察。结果表明，该科植物的孢子可分为3种类型：(1)孢子球形，三裂缝；周壁较厚，疏松地包在孢子之外；外壁光滑，表面纹饰由周壁形成，呈网状、嵴状、刺状或皱状。除金粉蕨属Onychium和珠蕨属Cryptogramma外，该科其他属的植物都具此类型孢子。(2)孢子钝三角形，三裂缝；周壁较薄，由周壁和外壁共同形成表面轮廓，表面具疣状或颗粒状纹饰。具此类型孢子的只有珠蕨属。(3)孢子钝三角形，三裂缝，沿裂缝两侧各有一脊状隆起或瘤状纹饰；周壁薄，由外壁形成表面纹饰的基本轮廓；具赤道环、近极脊和远极脊。具此类型孢子的只有金粉蕨属。另外，从孢粉学的角度对该科的分类和系统演化进行了探讨。 相似文献
16.
栎属青冈亚属（壳斗科）的叶表皮研究 总被引：1，自引：0，他引：1
利用光镜和扫描电镜观察了栎属青冈亚属Quercus subgen. Cyclobalanopsis 48种植物的叶表皮，尤以对叶下表皮的毛被特征观察较为仔细。共观察到8种不同类型的叶表皮毛：单列毛、单毛、乳突、星状毛、溶和星状毛、具柄束毛、多出毛和水母状毛。其中乳突在青冈亚属中较常见，而在壳斗科其他属中仅在石栎属 Lithocarpus 少数种类中有报道；水母状毛首次在壳斗科中发现。毛被可能遵循以下的演化规律：乳突→单毛→星状毛；星状毛依照从简单→复杂的演化途径，分化出各种形态各异和结构复杂的毛系。初步讨论了毛被以及叶表皮其他特征(如毛基细胞和表皮细胞的形态、气孔的类型和密度等)的分类和系统学意义。 相似文献
17.
中国主要禾本科植物颖果形态的基本类型与系统分类 总被引：2，自引：0，他引：2
本文在观察了31个族109个属324种禾本科植物果实形态的基础上，探讨了重要性状演化的趋势及其与分布区和生境条件的关系。根据果实大小，整体形状，腹面和脐的形态，胚与果的长度比值，果端有无茸毛，花柱是否宿存，尤其横切面轮廓等，将禾本科的颖果形态划分为三大类型七个亚型。 经过与细胞染色体、胚体、幼苗和植株各方面数据的互相印证，证明与颖果形态的七个基本类型相对应，在系统分类上是七个亚科。 相似文献
18.
郎楷永 《中国科学院研究生院学报》1983,21(3):254-265
Situated in western part of Sichuan Province, 29°30'N, 103°20'E, the sacred Mt.
Emei is one of the well-known large mountains in China. Its summit is about 3100 m ab-
ove sea level with a relative height of 2550 m.
The orchid flora in Mt. Emei so far known comprises 47 genera and 109 species,
among which 21 are epiphytes, 83 terrestrials and 5 saprophytes (Table 1.)
1. The vertical distribution of the orchid flora in the mountain.
The epiphytic orchids are concentrated in the lower region below Hongchunping
and Wanniansi (1100 m alt.), where there are 20 species, which make over 95% of epiphytic
species; the upper limit for the epiphytic orchids is Jiulaodong and Chudian ( 1800 m alt.).
The terrestrial orchids also mainly occur at the lower region below Jiulaodong and Chudian (1800 m alt.), where there are 54 species, most of which are found at even lower part of the mountain, below Hongchunping and Wanniansi (1100 m alt.). The tropicas orchids in the mountain, such as Cleisostoma, Vanda, Holcoglossum, Tropiclia, Thunia, Mischobulbum, Ludisia, Anoectochilus, Odontochilus, etc. all grow only at the lower part of the mountain below Hongchunping and Wanniansi (1100 m alt.).
2. The floristic features of the orchid flora in the Mt. Emei.
(1) The orchid flora in the mountain so far known comprises 47 genera (over 2/3
of the total orchid genera in Sichuan) and 109 species (over 1/3 of the total orchid species in Sichuan). The Mt. Emei is very rich in orchid species, as compared with neighbouring
mountains of same magnitude, such as Mt. Shennonjia in western Hubei, Qin Ling in sou-
thern Shaanxi, Jinfo Shan in south-eastern Sichuan, and Erlang Shan in western Sichuan.
(2) The orchids in the mountain are complex in floristic components as indicated
below:
1) Twenty seven species, belonging to 18 genera, are widespread, covering the whole East-Asian region.
2) Twenty three species, belonging to 15 genera, are the elements of the Sino-Japanese Subregion. Among them 13 species occur only in Japan and eastern China with the mountain ar the westernmost limit, but the other species extend westwards as far as Kangding and ErLang Shan or Baoxing in Sichuan Province.
3) Forty two species, belonging to 22 genera, are the elements of the Sino-Himala-yan Subregion, with 5 species having their range extending from the Himalayan region
eastwards to Mt. Emei.
4) Some tropical genera (8 species), belonging to Indo-Malaysian floristic elements, have the mountain as their northern limit of distribution.
The orchid flora of the Mt. Emei contains not only the East-Asian elements, but also some Indo-Malaysian elements, though its composition is mainly of the temperate and subtropical Eastern Asian (Sino-Japanese) ones.
(3) The orchid flora in the mountain is characterized by geographical vicariation and differentiation.
There are nine species-pairs (belong to genera Calanthe, Platanthera, Dendrobium etc.) of the vertical vicarism and six species-pairs (belonging to genera Tropidia, Aneoctochilus, Mischobulbum, Gymnadenia Orchis, etc.) of the horizontal vicarism in the Mt.
Emei.
Remarkable differentiation of orchid flora in the Mt. Emei is shown in the abundance of endemic elements and as clear geographical vicariation.
(4) There are 8 endemic species and one variety of orchids in the Mt. Emei, more
abundant than in Xizang. The floristic features of the orchid flora of the Mt. Emei are rich in species, compara tively complex in components, rather prolific in endemic species, and characterized by geographical vicariation and differentiation. The orchid flora in the Mt. Emei mainly consists of the subtropical and temperate East-Asian elements, with a considerable proportion of tropical elements though. 相似文献
19.
本文详细讨论了苄基异喹啉生物碱的生源和进化趋势，化学结构类型的分布规律，植
物来源，药理作用以及它们之间的联系性。研究表明：苄基异喹啉生物碱主要存在于较原始
的木兰亚纲植物群中，阿朴菲型、双苄基异喹啉型、原小檗碱型为普遍存在的结构类型。由于
按生源路线产生的不同结构类型在植物中呈现有规律的分布，因此苄基异喹啉生物碱可作为很好的分类学指标。 相似文献
20.
利用整体透明、石腊和薄切片方法对芸香科22属,40种和2变种植物叶分泌囊的形态结构和分
布进行了比较研究。成熟分泌囊都由鞘细胞和一层上皮细胞围绕圆形腔隙构成,上皮细胞扁平,细胞壁
薄、完整,故分泌囊属裂生方式发生。鞘细胞1～5层,不同种类的层数有变化,个别种缺乏。内层鞘细
胞为扁平的薄壁细胞,外层的细胞壁较厚。分泌囊的形态结构、着生位置和分布密度等在不同属或不同
种间存在一定差异。根据分泌囊在叶中的分布位置和形态结构特点,可将其划分为:叶缘齿缝分泌囊,
叶肉分泌囊和两者混合型。叶肉分泌囊又可分海绵组织分泌囊和栅栏组织分泌囊。在此基础上对该科各类型分泌囊的形态演化关系以及各亚科或各属间的亲缘关系进行了探讨。 相似文献