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1.
本文对鬼灯檠属Rodgersia Gray的染色体数、花粉体积和纹饰、萼片数目、萼片脉序和脉型、萼片腹面毛被、花梗和花序轴毛被、叶的类型等关键性状进行了分析,确定了其进化顺序,依据性状的系统发生,绘制了鬼灯檠属的瓦格勒尔系统树;确认本属有5种和3变种,其中以R.podophylla为最原始,R.nepalensis为最进化,而R.aesculifolia,R.sambucifolia.和R.pinnata则居于两者之间。本属分两组Sect.Rodgersia,仅含R.podophylla Sect.Sambucifolia J.T.Pan,含R.aesculifolia,R.sambucifolia,R.pinnata,R.nepalensis。依据种的主要分布区,划本属植物为4个分布类型,即:日本—朝鲜间断分布,秦岭—大巴山分布,横断山分布和东喜马拉雅分布。笔者认为,本属的起源地在日本-朝鲜一带,横断山地区是其现代分布中心和分化中心;本属的散布路线是自日本—朝鲜,经秦岭—大巴山,通过横断山地区而进入东喜马拉雅,本属的起源时间,当在晚第三纪以前(晚白垩世至早第三纪)。此外,还报道了鬼灯檠属植物的花粉形态。  相似文献   

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 This article deals with the distribution of triterpenoids in Chinese: species of Panax.  The results of investigation show that the tetracyclic triterpenoids of dam- marane type are the main constituents in Ginseng (P. Ginseng C. A. Meyer) and Sanchii (P. notoginseng (Burk.) F. H. Chen) and that pentacyelic triterpenoids of oleanane type are the main constituents in P. pseudo-ginseng Wall., P. zingiberensis C. Y. Wu et K. M. Feng, P. japonicus C. A. Meyer and its variety (var. angustifolius, var. major, var. bipinnatifidus) and P. stipuleanatus H. T. Tsai et K. M. Feng.  The fact that the Chinese people had found out herbs with such high therapeutic effects as Ginseng and Sanchii through long medical practices shows it to have been achieved not without modern scientific ground.  Tetracyelic triterpenoids of dammarane type is one of the active constituent of Ginseng and Sanchii, while, on the contrary, the pentacyclic triterpenoids of oleanane type have yet inactive physiologic properties. '      Through the comparative study of triterpenoids constituents together with the taxonomy and the geographic distribution of various species of Chinese Panax, it shows that Panax as a whole may be divided into two main groups: the first group, having rather short erect rhizomes, fleshy carrotlike roots and larger seeds, is cor- responding to those species with their main constituents as the tetracyclic triterpenoids of dammarane type and their areas in dispersal being often limited and disjunct. The second group, that possesses long creeping rhizomes, usually with no well developed fleshy roots and bearing smaller seeds, correlates to those species invariably with continual distribution and their main constituents are pentacyclic triterpenoids of oleanane type.  Therefore, it is suggested that in comparing with the latter group, the former is perhaps more primitive, and Sanchi  (P.  notoginseng  (Burk.)  F.  H. Chen) may be the oldest member among living species of Panax. On the other land, it is found that in external morphology, P. pseudo-ginseng Wall. belongs to the former group, but its chemical constituents are nevertheless similar to the latter.  On such account, it seems evident that P. pseudo-ginseng Wall. constitutes a transitional type between these two groups, and reveals there by some historical relationship of thesetwo groups.  相似文献   

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滇池是云南高原上的一颗明珠,是风光秀丽的国家级旅游度假区。它与昆明人民的生活息息相关,滇池不但是昆明地区工农业用水和生活用水的主要来源之一,也是水产品的重要生产基地,同时还具有调节气候、维护地区自然生态平衡、保护当地人民健康的重要作用。  相似文献   

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桦木科植物的系统发育和地理分布(待续)   总被引:1,自引:0,他引:1  
本文对桦木种植物的研究历史作了详细的总结。在钻研文献的基础上,补充了部分系统学资料,使得花序、花,花粉、叶表皮等各类性状能够在属间进行比较。根据外类群比较、和谐性分析等原则确定了性状的演化极性,利用最大同步法和最小平行演化法对桦木科植物进行了分支分析。对各属的现代分布和地史分布作了描述,在此基础上,讨论了桦木科植物的分布中心、起源地、起源的时间和散布的途径。作者试图回到遥远的晚白垩纪和早第三纪,从描绘桦木科植物起源和早期分化的古地理和古气候背景人手,分析了在这种背景下桦木科植物所发生的空间辐射以及植物体本身所产生的形态进化,以求得对桦木科植物起源、散布和分化作出比较合理的解释。最后对桦木科组以上的等级作了分类处理。  相似文献   

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桦木科植物的系统发育和地理分布(续)   总被引:1,自引:0,他引:1  
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 橐吾属Ligularia Cass.是菊科千里光族款冬亚族的一个大属。在款冬亚族中本属与大吾风草属 Farfugium Lindl.亲缘关系最近,但进化程度较高。本属包括6组,11系129种。所有种类均分布在 亚洲,仅2种扩散至欧洲。在东亚地区有119种,占该属总种数的96%。高度集中在横断山区的有4组、 6系67种,其中61种为特有种,占该属总组数的66%,总系数的54.5%,总种数的52%。这个事实 表明了横断山区是该属的多度中心和多样化中心。通过性状分析,伞房组伞房系Sect.Corymbosae, Ser.Calthifoliae叶肾形,具掌状叶脉,头状花序大而少,排列呈伞房状,总苞半球形,被认为是该属的 原始类群。原始种齿叶橐吾L. dentata和鹿蹄橐吾L.hodgsonii的分布区从我国四川东部经过湖北、湖 南、安徽、福建等省至日本。这个分布格局与近缘属大吴风草属Farfugium一致。     根据共同起源原理,这两个属的祖先极有可能就发生在这一地区。因此我们推测东亚地区从中国四 川东部至日本这一地区是本属的发源地,然而根据地质历史和现代分布,作者认为中国中部(包括四川 东部)是本属的初始起源地。该属起源后,基本上沿亚洲南缘的山地扩散,少数种类向东北至亚洲东北部。本属起源时间至少不晚于中白垩纪。  相似文献   

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青藏高原柳属植物的发生和分布   总被引:2,自引:0,他引:2  
  1.  Uplifting of Qinghai-Xizang plateau has brought great influence on the origina- tion and distribution of species inside the genus Salix.  There are 91 sp. (incl. 2 cult. sp.), 16 var. and 3 f. belonging to 15 Sect. in this region, among these species the en- demics attain to 58 sp., 14 var. and 3 f.  So it has become one of the most important centres of distribution of Salix in the world. Species common with other regions attain only to 32.  Thus it is also clear that correlation between salicaceous flora in this re- gion and that of other regions is not so much developed, and that the salicaceous flora of Qinghai-Xizang plateau was mainly originated autochthonously during the upheaval of plateau.      2. Along a demarcation line delineated from Gyirong through Lhasa and Qamdo to Lanzhou, to the north-western region the total number of species of this genus is sum- med up to 7 sp. and 1 var. (incl. 2 cult. sp.), and they distribute only in the West Hima- laya and Pamir-Kunlun regions.  Besides 2 cult. sp., there is only 1 endemic, and others all should be migrants from Europe or West Asia. In the south-eastern part, be- cause the climate is moister, the species of Salix may be summed up to 84 sp., 15 var. and 3 f., among them 73 sp., 20 var. and 3 f. are endemics, accounting for 68 percent of the total.       3.  In East Himalaya and South Henduan Shan (southward of lat. 30°N.) there are 78 sp., 12 var. and 4 f., among them 50 sp., 10 var. and 2 f. are endemics.  They represent the different stages of phylogenetic development of this genus.  So here may be the centre of origination and distribution of Salix species in the all Sino-Himalaya flora. The common species between East Himalaya and South Henduan Shan regions attain to 41. Because the latter forms a part of Sichuan and Yunnan plateau and the former did not become a land until Quaternary Period, the plants of the former mainly are the migrants from the latter.      4. The most characteristic group of Salix in this  region  is  Sect. Lindleyanae Schneid. with a total of 18 sp. and 1 var.  This group adapting to the somewhat en- vironment changes is quite different from Sect. Retusae A. Kern. in the Arctic and high mountains of higher latitudes in many characters, so it should be originated autochto- nously, and it is certainly not a migrant from Arctic. This Sect. seems to be developed from Sect. Floccosae Hao and in turn from Sect. Sclerophyllae Schneid. and Sect. Den- ticulatae Schneid.  This developmental direction has assumed an important branch in the phylogenetic development of the whole genus.      5.  In addition, there are two interesting and important regions on the north-eastern and eastern to Qinghai-Xizang Plateau, i. e. on the north-east Anymaqen Shan (Amne- machin mountain) and on the east Qiong Lai Shan.  There are many endemic species pertaining to these two parts, among these species some may be ancient relicts since Tertiary. It is to be expected that more additional scientific results will be obtainedafter some more extensive works done in these two regions.  相似文献   

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中国针茅属分类、分布和生态的初步研究   总被引:1,自引:0,他引:1  
 24 species and 4 varietes of genus Stipa L. of China have been studied and des- cribed in this paper.  It has been noted that  these  different  species  have various geographical distributions, depending on the changes of climatic and edaphic factors of their environments.  Based on the study of floral morphology together with ecolo- gical and distributional factors, the genus have been divided into 5 sections: 1.  Sect. Regelia Tzvel. 2. Sect. Leiostipa Dum. 3. Sect. Barbatae Junge 4. Sect. Stipa 5. Sect. Smirnovia Tzvel.       It should be pointed out that the section Regelia as well as two members of sec- tion Barbatae, S. purpurea and S. roborowskyi, belong to frigori-xerophilous ecotype, distributing over Qinghai-Xizang Plateau above the forest line.  The section Leiostipa belongs to euxerophilous and mesoxerophilous ecotype, distributing widely in north- west, southwest, northeast and east and extends to the forest-steppe vegetational Zone of China.  The section Smirnovia and other two members  of section Barbatae,  S. breviflora and S. orientalis, belong to euxerophilous ecotype, with the latitudinal dis- tribution as far as Nei-Mongo and the yellow soil plateau, with the altitudinal distribu- tion as far as the desert steppe of Sinkang and Qinghai-Xizang plateau.  The section Stipa belongs to euxerophilous ecotype, only distributes to the  mountain steppe  of north Xingkang and the last, section Barbatae is an artificial group having plumes overof the awn only, and its four species have already been mentioned above.  相似文献   

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分析了从传统文献分类法到信息分类法和分众分类法的发展过程,论述了信息分类法和分众分类法在网络中的应用,阐述了分众分类法的发展趋势.  相似文献   

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菊科一新属——紊蒿属   总被引:1,自引:0,他引:1  
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产业共性技术:概念、分类与制度供给   总被引:16,自引:0,他引:16  
本文分析了产业共性技术的概念、特点以及失灵的制度供给.论文认为,产业共性技术对于中国具有重要的意义,特别是考虑到我国产业科研院所的体制改革以及众多产业集群的发展.论文对产业共性技术的已有定义进行了总结,提出了几种分类.最后,论文讨论了我国产业共性技术制度供给的几种办法.  相似文献   

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测定了红豆杉科、三尖杉科、罗汉松科及松科共9属13种植物的matK基因序列,发现3′端的单碱基插入造成mat k基因在这些类群间有较大的长度变异(1488∽1548bp),其它插入或缺失的长度为3、6或9bp(白豆杉中有一个长为27bp的缺失),且绝大多数插入或缺失事件具有系统发育信息。matK基因中,密码子第1、2及3位的变异率较为相近,平均同义替代率约为平均非同义替代率的2倍。以松科2属3种植物为外类群,运用PAUP软件进行的系统发育分析仅得到一棵最简约树(步长为895,CI=0.850,RI=0.876),该简约树的各分支均得到bootstrap分析的极强支持。结果表明:红豆杉科与三尖杉科均为单系群,二者互为姐妹群;白豆杉属与穗花杉属为红豆杉科中两个很自然的属,白豆杉属为红豆杉属的姐妹群,穗花杉属为榧树属的姐妹群。竹柏属与罗汉松属聚为一支,二者间的亲缘关系得到boot-strap分析的100%支持,从分支分类学及遗传距离角度,作者不赞同将竹柏属提升为科。  相似文献   

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