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1.
Aristolochia Subgen. Pararistolochia ( Hutch. & Dalz. ) O. C. Schmidt, a smallest one among so far known three subgenera in the genus, often treated as a separate genus, is composed of only nine species from Tropical Africa (8 species)and Tropical Asia ( l species). This work deals mainly with the system and taxonomic treatment as well as distribution based on the herbarium materials form British Museum (Natural History) (BM), National Botanical Garden of Belgium(BR), Royal Botanic Gardens of Kew(K) and Laboratoire de Phanerogamie of Paris(P). Three sections in the subgenus are described as new by the number of anthers and its arrangement. Also two names, Pararistolochia zenkeri (Engl.) Hutch. & Dalz. and P. macrocarpa (Duch.) Poncy var. soyauxiana(Oliv. )Poncy, are reduced to synonyms of A. macrocarpa Duch.; andone name, A. preussii Engl., is reduced to a synonym of A. promissa Mast.  相似文献   

2.
Shre.  KK 《植物分类学报》1997,35(5):396-433
Cyananthus Wallich ex Bentham, the only genus of Campanulaceae with superior ovary, is revised to clarify infrageneric relationships and phylogeny of the genus. Evidence obtained from the comparative gross morphology, anatomy, palynology, and karyomorpho-logy recommends a new infrageneric classification of the genus, recognizing 23 species, belonging to two subgenera, four sections and four subsections. One subgenus(Subgen. Mi-cranthus), one section(Sect. Suffruticulosi) and two subsections(Subsect. Flavi and Sub-sect. Lichiangenses)are described as new taxa. New combinations at sectional (Sect. Annui) and subsectional(Subsect. Stenolobi) ranks are also proposed. The genus Cyananthus is strictly distributed in the high mountains of China(Xizang, Yunnan and Sichuan), extending to Bhutan, Nepal and India (Kumaon-Garhwal, Assam and Sikkim), with altitudinal ranges from 2500 ~ 5300 m. It is observed that 13 species are endemic to SW China and only three species are endemic to the Himalayas( two species in Ne  相似文献   

3.
中国栎属(壳斗科)基于叶表皮及叶结构特征的分支分析   总被引:13,自引:1,他引:13  
以三棱栎为外类群,基于叶表皮及叶结构特征对中国栎属进行初步的分支分析,结果显示了栎属内稳定的“支”结构及其种间关系。栎亚属可划分为5个组,分别为巴东栎组,高山栎组,Jiang子栎组,麻栎组和槲栎组,Jiang子栎组是栎亚属常绿栎类与落叶栎类之间的过渡类群;高山栎组应为栎亚属常绿栎类中的特化类群,而非最原始类群,5个组中,仅巴东栎组不是单系类群,而是一个多系类群,青冈亚属较栎亚属早分支,可划分为3大类;无毛类,简单被毛类和复杂被毛类;无毛类最原始,复杂被毛类与栎亚属关系最近,因此,叶表皮及叶结构特征对解决栎亚属组间亲缘关系有重要的分类学意义。  相似文献   

4.
The geographical distribution of Aconitum in the Sino-Himalayan subregion is analysed in the present paper on the basis of taxonomy and relationship between the infrageneric taxa. Asaresult, some conclusions may be arrived as follows: 1. The Sino-Himalayan subregion is the frequency centre and the diversity centre of the genus. For analysis, the distribution area of the genus are assigned to three floristic regions, viz. 1) the East-Asian floristic region, consisting of the Sino-Himalayan subregion and SinoJapanese subregion, 2) the Euro-Siberian region and 3) the North-American region (Table 1). In the East-Asian floristic region, the Sino-Himalayan subregion comprises 3 subgenera, about 5 sections, about 13 series and nearly 180 species. However, the Sino-Japanese subregion has only 2 subgenera, 2 sections. 6 series and about 50 species. The Euro-Siberian region has 2 subgenera, 2 sections, about 9 series and nearly 70 species. The North-American region has 2 subgenera (one of the 2 subgenera has only 1 species), 1 section, 1-2 series and about 26 species. Obviously, the Sino-Himalayan subregion is the richest in taxa. 2. The Sino-Himalayan subregion is not only the preservation centre of the primitive groups and species, but also an actively differentiating region. Largely in the Sino-Himalayan subregion occurs primitive or more primitive tava in the genus, such as Sect. Fletcherum, Sect. Alatosperum and Sect. Sinaconitum, Ser. Tangutica and Ser. Brunnea etc.: A fletcherianum, A. novoluridum, A. chrysotricum, A. brevicalcaratum, A. polycarpus, A. nagarum, A. tanguti cum, A. hookeri, A. naviculare, A. violaceum, etc. On the other hand, the Sino-Himalayan subregion also has the most or relatively advanced taxa, represented by the annual monotypic subgenus Gymnaconitum, A. spiripetalum, A. hamatipetalum and A. bulbitiferum ect. About 50 infraspecific taxa occur in the subregion. For example, A. hemsleyanum has 8 varities, A. franchetii has varities and A. nagarum 1 varity and 2 forms, ect. 3. In the region under discussion the genus Aconitum shows remarkable endemism. The endemic taxa include 3 sections (Sect. Fletcherum, Sect. Alatosperum and Sect. Sina conitum), 3 series (Ser. Brevicalcarata, Ser. Crassiflora and Ser. Bullatifolia) and nearly 150 species, among which primitive and advanced ones are both present. 4. The pattern of geographical distribution of the genus Aconitum shows remarkable relationship between latitude and altitude. The majority of species of this genus prefer habi tats with a cool and more or less constantly moist climate. In the Sino-Japanese subregion, with a higher latitude, the genus has an altitude range of 500-1500 m, whereas in the Sino-Hima-layan subregion the range is 2900-5000 m. To sum up, the Sino-Himalayan subregion is the diversity centre, the frequency centre, the differentiation centre, the preservation centre of the primitive taxa and the centre of endemism of the genus Aconitum, and its development in this subregion has probably been accelerated by the lift of the Himalayas and the complicated environmental conditions.  相似文献   

5.
分析了171个中国蒿属植物样品的精油化学成分,鉴定出305个化合物。这些样品代表64个种,其中蒿亚属47种,龙蒿亚属17种。 分析结果表明,这些化合物在两亚属中的分布有一定的规律性。在蒿亚属精油中主要含单萜类和倍半萜类化合物,而在龙蒿亚屑精油中主要含倍半萜类化合物和芳香族化合物。这种分布与中国蒿属植物从较原始到进化划分为7个组的系统分类有一定的相关性,即蒿亚属:莳萝蒿组(单萜类化合物)→艾蒿组(单萜类化合物)→艾组(单萜类化合物)→腺毛蒿组(单萜类化合物和倍半萜类化合物)→白苞蒿组(倍半萜类化合物)。龙蒿亚属:龙蒿组(倍半萜类化合物和芳香族化合物)→牡蒿组(倍半萜类化合物和芳香族化合物)。  相似文献   

6.
The genus Gynostemma consists of 16 species and 2 varieties, which fall into two subgenera and two sections, i. e. , Subgen. Trirostellum including two new sections, Sect. Pentagynae and Sect. Trirostellae, and Subgen. Gynostemma. The modern distribution centre of the genus ranges from drainage areas of the Yangtze River to Yunnan, southwest China. Northwards, it is distributed to the south slope of the Qinling Range and the south branch of the Huaihe River, eastwards through central-eastern China to Korea Peninsula and northern Japan; in the south, it extends to Indo-China, Malaysia, Philippines, Indonesia and Papua New Guinea, with the west limit of this genus found in northwestern India.The distribution pattern of the genus indicates a nature of Tropical Asia Type. Based on the above mentioned distribution pattern, the centre of diversification and the ecological adaptation of both primitive and advanced groups, also by means of palaeogeological, palaeogeographical and palaeoclimatical evidence and the origin of its out group, the genus Gynostemma, together with its closely allied genera Hemsleya, Gomphogyne, etc. is considered to have originated on the Kham-Dian Oldland during the Early Tertiary.  相似文献   

7.
绞股蓝属植物的分类系统和分布   总被引:34,自引:0,他引:34  
绞股蓝属全世界有16种2变种,隶属于2亚属2组,即喙果藤亚属(包括五柱绞股蓝组和喙果藤组)及绞股蓝亚属。其现代分布中心或多样化中心为我国长江流域至西南的云南,由此向北达秦岭南坡和淮河流域以南,向东北经华中、华东至朝鲜半岛和日本北部,向南经中南半岛、马来西亚达菲律宾、印度尼西亚诸岛和巴布亚新几内亚,向西达印度西北部,为热带亚洲分布类型。根据该属的原始类群和进化类型的现代分布和多样化中心及它们的生态适应性,与古地质、古地理和古气候的变迁以及外类群起源地等推测,绞股蓝属植物可能与其近缘属——雪胆属和锥形果属共同起源于康滇古陆,起源时间可能为早第三纪。  相似文献   

8.
Juncus Linn. is a cosmopolitan genus with about 240 species, widely distributed in both hemispheres, but most abundant in the frigid and temperate zones. In the present paper, a revision of this genus in China is made, and a key to the species is provided. This paper also presents a systematic arrangement of the genus Juncus Linn. from China, recognizing six subgenera, 14 sections (includ. ten new), four series (includ. two new), 77 species (includ. 14 new), one subspecies (new) and ten varieties (includ. four new). They are as follows: Subgen. 1. Genuini Buchen. Sect. 1. Inflexi K. F. Wu, sect. nov. Sect. 2. Effusi (V. Krecz. et Gontsch. )K. F. Wu, stat. nov. Subgen. 2. Pseudotenageia V. Krecz. et Gontsch. Sect. 1. Kangpuenses K. F. Wu, sect. nov. Sect. 2. Compressi (V. Krecz. et Gontsch. )K. F. Wu, stat. nov. Sect. 3. Tenues (V. Krecz. etGontsch.)K. F. Wu, stat. nov. Subgen. 3. Poiophylli Buchen. Sect. 1. Nigroviolacei K. F. Wu, sect. nov. Sect. 2. Bufonii (V. Krecz. et Gontsch. )K. F. Wu, stat. nov. Subgen. 4. Graminifolii Buchen. Subgen. 5. Septati Buchen. Sect. 1. Allioides K. F. Wu, sect. nov. Sect. 2. Articulati K. F. Wu, sect. nov. Ser. 1. Articulati V. Krecz. et Gontsch. Ser. 2. Dongchuanenses K. F. Wu, ser, nov. Subgen. 6. Alpini Buchen. Sect. 1. Triglumes K. F. Wu, sect. nov. Ser. 1. Triglumes K. F. Wu, ser. nov. Ser. 2. Benghalenses K. F. Wu, ser. nov. Sect. 2. Minimi K. F. Wu, sect. nov. Sect. 3. Sikkimenses K. F. Wu, sect. nov. Sect. 4. Concinni K. F. Wu, sect. nov. Sect. 5. Sphacelati K. F. Wu, sect. nov.  相似文献   

9.
The genus Ottelia is one of the great genera of Hydrocharidaceae. About 25 species distributed in the Palaeotropics, extending from Africa through India and SE. Asia to Korea and Japan, Australia and New Caledonia, 1 species in Brazil; centres of specific devolopment are found in Central Africa and SE Asia. The present study is mainly based on the materials collected during the field explorations in the lakes of Yunnan and observations on the structure of the spathe and flowers, the variation of leaf of the plants cultivated in Kunming Bot. Garden. Instead of the wings of the spathe used by Dandy, by the characters such as uni-or bisexual flowers, this genus is divided into two subgenera, which by the number of the flowers in spathe and the number of the carpus in ovary again subdivided into 4 sections. They are as the following: A. Subg. Ottelia. Flowers bisexual. Sect. 1. Ottelia. Spathe with 1 flower; ovary with 6(—9) carpus. Sect. 2. Oligolobos (Gagnep.) Dandy. Spathe with many flowers; ovary with 3 carpus. B. Subg. Boottia (Wall.) Dandy. Flowers unisexual; the male spathe with 1-many flowers, the female spathe with many flowers. Sect. 3. Boottia. The male spathe with 1 flower; ovary with 9(—15) carpus. Sect. 4. Xystrolobos (Gagnep.) H. Li. The female spathe with (2-) many flowers; ovary with 3 or 9 carpus. The Chinense species of ottelia is in great need for revision. All of the species in China previousely described under Ottelia Pers, Boottia Wall., Oligolobos Gagnep, and Xystrolobos Gagen. are here combined into 3 species. They are O. alismoides, O. cordata, O. acuminata with 4 variaties. After a study of the geographic distribution and infer relation-ships among the floristic elements it has been proved that Ottelia is certainly an ancient genus, and the primitive types came into being and widely dispersed before the separation of Laurasia from Gondwana. During a considerable period of time the elements of the genus Ottelia in freshwater environment of different continents have been separately differentiated and evolved into more or less derived types. The structure of flowers in all of the asian species shows the following evolutionary tendenoes: 1. In this genus the plants with unisexual flowers have evolved from plants with bisexual flower; 2. In the groups with bisexual or unisexual flowers the number of stamens and styles reduced to 3-merous, but the number of flowers in spathe increased. So that the subgenus Ottelia is more primitive than the subgenus Bottia; While in the subgenus Ottelia O. alismoides is a more primitive than O. balansae and in the subgenus Boottia O. cordata is the most primitive, butO. alata seems to be the most advanced.  相似文献   

10.
中国灯心草属植物的研究   总被引:8,自引:0,他引:8  
本文通过对国产灯心草属植物的研究,提出了一个中国灯心草属分类系统排列,首次确认我国产6亚属,14组(包括10个新组),4个系(包括3个新系),77种(包括14个新种),l亚种(新亚种)和10变种(包括4个新变种),对其中一些种类作了归并及处理。  相似文献   

11.
李俊  任毅 《西北植物学报》2008,28(2):267-271
对马兜铃属植物北马兜铃(Aristolochia contorta Bge.)花形态发生的扫描电镜观察表明:其花萼在发生时与苞片相似,6枚雄蕊呈4枚先发生、2枚后发生的方式,心皮的发生以6个胎座突出到子房室中为特征,由侵入的侧膜胎座合生为中轴胎座。在胎座发生发育过程中,在花药的腹面各产生一个突起,此突起后来与胎座上端相连,最终发育为合蕊柱裂片。结合文献资料,我们认为北马兜铃的花被与苞片是同源的,其合蕊柱裂片来自于雄蕊,中轴胎座是次生的。  相似文献   

12.
Studied in this work was seed morphology of the genus Plantago (2 subgenera, 8 sections, 17 species and 1 variety )in China. The sculpture was observed under scanning election microscope. Four forms of seed morphology are recognized as follows: (1)Multi-angular type: seeds are variously angulate, yellow-brown or black, 6-30 in a fruit; seed-coat sculpture ranges from reticulate to papillate. It occurs in Subgen. Plantago Sect. Polyneuron: P. scheideri, P. denstflorus, P. major, P. hostifolia, P. asiatica, P. erosa and P. centralis. (2) Navicular type: seeds are navicular, yellow, brown to black, 2 in a fruit; seed-coat sculpture is reticulate. It was found in Subgen. Plantago Sect. Novorbis: P. virginica; Sect. Arnoglossum: P. lanceolata; Sect. Leucopsyllium: P. minuta, P. lessingii and P. aristata and Subgen. Psyllium Sect. Psyllium: P. indica. (3)Ovoid type: seeds are long-ovoid, yellow-brown, black and lustrous. Seed-coat sculpture scali-ratiform. P. maxima in Subgen. Plantago Sect. Lamprosantha belongs to this type. (4)Recti-circular type: seeds are recti-circular, yellow-brown, black, 1-2 or 4-5 in a fruit; seed-coat sculpture is reticulate and papillate. It was found in P. maritima var. salsa of Subgen. Plantago Sect. Coronopus and P. depressa, P. camtschatica and P. arachnoidea of Sect. Mesembrynia. The seed morphology and seed-coat sculture exhibit specific characters, by which some of confused species can be clarified and a new species, P. densiflorus J. Z. Liu. is established. The present author’s seed morphology classification is in accordance with Pilger’s systemof the genus, which was established using other features.  相似文献   

13.
论世界蒿属植物区系   总被引:15,自引:2,他引:13  
林有润 《植物研究》1995,15(1):1-37
本文从多学科, 包括形态、地理分布、孢粉、古植物、谱系分支分析及化学成分等学科的研究, 论述了世界蒿属植物的系统分类及其种属地理、历史地理和区系地理.  相似文献   

14.
基于trnK基因的葱属植物分子系统研究   总被引:3,自引:1,他引:2  
在形态和细胞分类研究的基础上选择产于中国的9组47种葱属植物(含外类群5种),运用PCR方法扩增叶绿体trnK基因,选择26种限制性内切酶对PCR扩增片段进行了RFLP分析.结果表明:trnK基因的PCR产物在各分类群间几乎不存在长度变异,约为2 520 bp,PCR扩增片段酶切后,共得到247个变异位点,其中信息位点201个.运用PAU P 4.0 B 10.0和M EGA 3.1软件进行分析,构建葱属系统发育的D o llo和W agner最简约(M P)树及邻接(N J)树.分析表明:(1)宽叶组类群组成比较自然的单系群,洋葱组和葱组也各自形成独立分枝,表明这3个组的划分是比较自然的.多籽组和合被组在本次分析中形成1个单系群,表明这2个组具有较密切的亲缘关系.而粗根组、根茎组和单生组的划分是不自然的,需进一步研究后作适当的调整.粗根组的类群在trnK基因的RFLP分析中,得到很好的分辨,可按其染色体基数分为3个大的类群.(2)中国葱属植物可以划分为6个亚属的新等级,在各亚属下可以再分组.(3)本文还对葱属的种间亲缘、进化关系等问题进行了讨论.  相似文献   

15.
According to chemical constituents, plant morphology and geographic distribution of Thalictrum in China, the relationships among sections in the genus are discussed in the present paper. The results show: 1. China is one of the major distribution centers of Thalictrum plants, with half of species endemic. Compared with species in other regions of the world, Chinese ones are relatively primitive. 2. From the chemosystematic point of view, the system of the genus adopted in Fl. Reip. Pop. Sin. is reasonable. 3. The main constituents of Thalictrum plants are benzylisoquinoline alkaloids. A correlation exists between the chemical patterns and plant evolution. The different sections are of different structure types. Aporphine-benzylisoquinoline and bisbenzylisoquinoline are major constituents in Sect. Leptostigma. Sect. Tripterium contains mainly aporphines, but non-alkaloid compounds are principal constituents in several species. In Sects. Thalictum and Schlagintweitella and Subgen. Leconyerium, types and content of alkaloids increase obviously and thus there are medicinal species. So these sections should be interested in developing some active constituents of antitumor, hypotenstion and antibacterium. 4. The genus occupies a special position in Ranunculaceae, as a transition to link the follicle plants and achene plants. Meanwhile, because the genus is rich in benzylisoquinoline alkaloids, the opinion that the Ranunculaceae, Berberidaceae, Menispermaceae andPapaveraceae form a natural group is even more strongly supported.  相似文献   

16.
(1) In the overwhelming majority of genera of the family Ranunculaceae, includ ing its primitive genera, Caltha, Calathodes, and Trollius and the primitive genus of trib. Anemoneae, Anemone, the sepals are spreading and the stamens are glabrous. So, the as cending or upright sepals and hairy stamens of the sections Meclatis, Tubulosa, Viorna, and Atragene of the genus Clematis are secondary, and are accordingly considered as advanced characters, and those sections and the genus Archiclematis, closely related to Sect. Viorna Subsect. Connatae, more or less advanced groups. (2) In the sections Cheiropsis, Fruticella, and Viticella, which have glabrous stamens,some species have spreading sepals, and the others have ascending or upright sepals. In Sect. Clematis, all the species have spreading sepals and glabrous stamens, except for Clematis pinnata, which has ascending sepals and usually hairy stamen filaments. In Sect. Lasiantha with 2 species restricted to western U. S. A., C. lasiantha has glabrous stamens, while C. paucifiora has stamens hairy on fliaments. In Sect. Naraveliopsis with spreading sepals,the majority of species have glabrous stamens, but one species, C.liboensis, endemic to Guizhou Province, China, has hairy stamens. These facts just mentioned indicate that the evolution of sepals and stamens took place in several lineages independently in Clematis. (3) In Clematis, glabrous stamens of C.apiifolia, C.grata, and C.montana with linear filaments and oblong anthers, are similar to those of Caltha, Calathodes, Trollius, and Anemone. Thus, the linear filaments and oblong anthers are considered primitive characters in Clematis. On the other hand, lanceolatelinear filaments of C. tangutica and C. aethusifolia or oblanceolate -linear filaments of C. courtoisii and C. loureiriana and linear anthers of C. meyeniana and C. uncinata, and narrow-linear anthers of C. courtoisii and C. lanuginosa are considered advanced ones. In ease of stamens with hairs, stamens of C. henryi with densely villous filaments and those of C. kweichowensis with both filaments and anthers densely pubescent show more advanced condition than those of C. pinnata, C. heracleifolia, and C. tangutica, with sparsely puberulous filaments and glabrous antbers(Fig. 1 ). (4)The pedunculate, 2-bracteate dichasial cyme with several flowers may represent the primitive type of inflorescences in Clematis. Manyflowered panicle-like cymes as in C.gouriana and C. tsaii, or few-l-flowered cymes as in C. henryi and C. repens, and cymes lacking peduncles and bracts as in C. montana and C. pogonandra are all considered advanced. Besides, the fact that flowers arise from axillary buds of old branches shows also an advanced condition. (5)Sect. Clematis subsect. Pinnatae, with leaflets, inflorescence ramification, and stamens similar to those of C. heracleifolia, is considered intermediate between Sect. Clematis and Sect. Tubulosa. (6) Subsect. Clematis and Subsect. Rectae, and Subsect. Connatae and Subsect. Crispae are so closely related to each other respectively that it is difficult to ascertain the systematic position of some intermediate species between the two subsections of each pair in the absence of seedlings. So, in the present paper, following the classification of Clematis proposed by Tamura in 1967, I put Subsect. Clematis and Subsect. Rectae in Sect. Clematis, and Subsect. Connatae and Subsect. Crispae in Sect. Viorna. (7)According to the evolutionary tendencies mentioned above, a realignment of the sections and the infrasectional taxa of the Chinese Clematis is made. (8) Six subsections, 6 serise, 2 species, and 4 varieties are described as new, and 5 new combinations, 4 new ranks, and 2 new names are given. (9)The specific rank of C. tenuipes W.T. Wang, reduced to varietal renk in 1980, is restord. C. taiwaniana Hayata, reduced to synonomy of C. grata Wall. in 1991, is considered distinct from the latter in hairy adaxial surface of sepal and narrower achene with tapering apex. C. kerriana Drumm. & Craib and C. laxipaniculata Pei are proved to be conspecific to C. subumbellata Kurz and reduced to syn-onymy.  相似文献   

17.
The genus Atraphaxis is found mainly in gravel steppes, sandhills and stony slopes or desert, with only a few species in meadow or river valleys. In China there are two sections and eleven species (including three varieties), which are distributed mainly in the northwest, with a few in the northeast and the north. Characters of the genus were compared and analyzed in the present work. Outer perianth segments 2, small, reflexed in fruit, inner perianth segments 2 or 3, large, erected and enveloping the nut. The embryo is curved, but those in the other genera of Atraphaxideae are straight. The curved embryo is the primitive character, because most species of the order Caryophyllales are of a circular embryo, which is belived to be ancestral in the Polygonaceae. The Pollen ornamentations of Atraphaxis are striate or striate-reticulate, different from those of the other genera. A new system of the tribe Atraphaxideae in proposed in the present paper. Based on the character analysis of the species in China, the present authors believe that Sect. Tragopyrum is more primitive than Sect. Atraphaxis. According to the distribution, the genus Atraphaxis might originate in Kazakstan, where not only are most species found, but also the most primitive species, like A. muchketovii, as considered by A. N. Krasnov, are found. Central Asia is considered as the distribution centre and origin centre of thegenus Atraphaxis.  相似文献   

18.
The genus Eurya was established by Thunberg in 1783 on a Japanese species E. japonica. Several decades later, many authors had made more or less intensive study on this genus. But in the earlier period, the different autherities had no clear conception of the genus. Thus Szyszylowicz (1893), Engler (1897) and Melchior (1925) entertained a much broader conception of this genus, including Freziera and Cleyera, both of which are now considered as distinct genera. A. Gray (1855), Vesque (1895), Urban (1896), and Kobuski (1935-37), however, concentrated their study only on the now accepted genus Eurya. Recently, a more detailed study of Chinese Eurya was made by Chang Hung-da (Acta Phytotax. Sin. 3 (1954) 1-59). But all of these authors did not subdivide this genus into more than subgenera except Vesque, who used the number of stamens and the septation of the anther cells to further subdivide this genus into 4 sections. In the present treatment, we base on the following characteristics to make subdivisions: the number of stamens, the septation of the anther cells, the hairness of the ovary, the length of the style, the shape and texture of the sepals, and the shape and hairness of the young branchlets. We assume that the morphology of the flowers has the following evolutionary tendencies: stamens from large (28) to small (5) numbers; anther cells from septate to nonseptate; ovary from being hairy to glabrous, styles from 5-4 free to 3 and more or less connate, from 2-6 mm to 0.5-1 mm long, and ovules from many (60) to few (2-4) in each cell. The genus Eurya has now about 140 species, being divided into 2 subgenera: Subg. Ternstroemiopsis Urban, with 2 species endemic in Sandwich Islands and Subg. Eurya with 138 species, in Asiatic tropic and subtropic regions and southwestern Pacific Islands. According to the characteristics mentioned above, we divide the second subgenus into 2 sections and 8 series, as follows: (I) Sect. Meristotheca Vesque (II) Sect. Eurya Ser. Ciliatae Hu et L. K. Ling Ser. Longistylae Hu et L. K. Ling Ser. Trichocarpae Hu et L. K. Ling Ser. Rigidisepalae Hu et L. K. Ling Ser. Tetragonocladae Hu et L. K. Ling Ser. Nitidae Hu et L. K. Ling Ser. Muricatae Hu et L. K. Ling Ser. Brevistylae Hu et L. K. Ling In China, the subgenus Eurya distributes east from Taiwan, west to the western part of Szechuan and Yunnan, and south from Hainan, north to the southern slope of Tsin-ling Range. The region north from southern part of Nan-ling Range, southwest to southeast Yunnan, south to northern part of the Peoples Republic of Vietnam, seems to be the centre of both maximum variety and frequency of this subgenus, for the number of species and the representatives of more primitive taxa in this region are much richer than in any other regions of the world. From this centre going northeast to Japan and Korea, west to eastern part of India, south to Java and Sumatra, north to the southern slope of Tsinling Range, the number of species and types gradually decreases, and especially the primitive series and species rapidly disappear. In addition, many species are also found in the Island of Irian, which we incline to consider as another young centre of development for this subgenus. Furthermore, according to the distribution of quite a large number of the species in China, we can recognize several boundary lines which are in agreement with the limits of the floristic and geobotanic provinces of China. In this article we have enumerated 80 species, and 11 varieties of the genus Eurya of China, among which are published for the first time 11 new species and 1 new variety, one species, E. persicaefolia Gagnepain, is first recorded from China, a number of specific names have been restored and a number reduced to synonyms. They are as follows: Restored species: Eurya acuminatissima Merrill & Chun E. patentipila Chun E. henryi Hemsley Reduced to synonyms: Eurya parastrigillosa Hsu ( E. patentipila Chun) E. changii Hsu (E. fangii var. megaphylla Hsu) E. chienii Hsu (E. persicaefolia Gagnepain) E. hwangshanensis Hsu (E. saxicola Chang) E. fangii Rehd. var. glaberrima Hsu (E. cavinervis Vesque) E. pseudopolyneura Chang (E. impressinervis Kobuski) E. longistyla Chang (E. stenophylla Merrill) E. huiana Kobuski f. glaberrima Chang (E. muricata Dunn) New combination: Eurya muricata Dunn var. huiana (Kob.) Hu et L. K. Ling E. aurea (Levl.) Hu et L. K. Ling  相似文献   

19.
This paper reports the result of comparative anatomical studies on medicinal roots of 53 species and varieties in the genus Aconitum from China. The anatomical structures of the roots can be classified into 6 types and 18 subtypes according to the level of their evolution. The anatomy of Aconitum roots is discussed in relation to phylogeny based on chemotaxonomy, cytology and other related disciplines. It was found that the six types of Aconitum roots are correlated with chemical components, chromosomes, toxicity and the gross morphology. The relatively advanced Types I and II roots always contain highly toxic alkaloids of diterpenoid diester of aconitine type, distributed mainly in Ser. 3, 5-11 of Sect. Aconitum of Subgen. Aconitum, while the relatively primitive Types III, IV and II roots with small diameters contain mainly atisine and aminal alcohol alkaloids, which have lower toxicity, present in Subgen. Gymnaconitum and Ser. 1, 2 of Sect. Aconitum of Subgen. Aconitum. The primitive Types V and VI roots of Subgen. Lycoctonum contain mainly the most low-toxic alkaloids of lycoctonine Type. The result is of significance both in theory or practice for the development of medicinal plant resourcesand the safety of clinical usage of these of plants.  相似文献   

20.
Comparative investigation on the inner surfaces of needle cuticle of Pinus was made for 17 species and two varieties under SEM. It is shown that the differences in protrusions and depressions of the internal cuticle surfaces of needles in the genus are not remarkable. However, the features of intercellular flanges are rather distinct and three types can be distinguished. They are: (1) Subgen. Strobus (Sweet) Rehd (except Sect. Parrya) is of the Pinus koraiensis type; (2) Subgen. Pinus is of the P. tabulaeformis type; (3) Sect. Parrya Mayr of Subgen. Strobus (Sweet) Rehd is of the P. bungeana type. The character may provide taxonomy of the genus Pinus with a new piece of evidence. Based on the features mentioned above, together with many others, such as wood anatomy, warts of wood tracheids, bark structure, needle anatomy and cuticle structure as well as karyotypic analysis in Pinus, the author considers that division of Pinus into two subgeuera is natural and that separation of Sect. Parrya Mayr from Subgen. Strobus (Sweet) Rehd. and thesubsequent establishment of the subgenus Parrya of its own are also reasonable.  相似文献   

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