首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 62 毫秒
1.
2.
橐吾属一新种   总被引:1,自引:0,他引:1  
多年生草本。根稍带肉质,较细,疏被短柔毛,茎细瘦,直立,高30~60cm,连同花序密被黄褐色短柔毛夹疏的白色柔毛,基部直径3~6mm,被褐色枯叶柄纤维包围。丛生叶及茎基部叶具短柄,柄长2~4cm,有翅、基部扩大成鞘状,茎中上部叶不具柄而半抱茎;叶片倒宽卵形,卵形或长圆形,长  相似文献   

3.
中国菊科橐吾属一新种   总被引:4,自引:0,他引:4  
中国菊科橐吾属一新种*张勉赵显国王峥涛徐珞珊徐国钧余国奠(中国药科大学,南京210038)ANEWSPECIESOFLIGULARIA(COMPOSITAE)FROMCHINAZhangMian,ZhaoXianguo,WangZhengtao,Xu...  相似文献   

4.
对近年来橐吾属植物的研究文献进行综述,主要内容有该属植物的化学成分、药理作用及其它方面的研究情况。  相似文献   

5.
甘肃橐吾属植物一新种   总被引:2,自引:0,他引:2  
直立草本。茎高70~85cm,具多数明显纵棱,中空;基部直径0.5~Icm,埋人土层部分深达5~7 cm,淡黄色,光滑;上部及花序轴被白色蛛丝状毛。叶灰绿色,直立,无  相似文献   

6.
橐吾属新分类群   总被引:1,自引:0,他引:1  
1 楔舌橐吾 新种 图1LigulariacuneataS.W.LiuetT.N.Ho,sp.nov.Fig.1SpeciesL.retusaeDC.similis,sedcaulibussupernepedunculisquebreviterflavopilosis,  相似文献   

7.
7种橐吾属植物的核型   总被引:5,自引:2,他引:5  
研究了7种橐吾属(Ligularia)植物的染色体和核形态。干崖子橐吾(L.kanaitzensis)的核型为2n=2x=58=26m+28sm 4st;窄头橐吾(L.stenocephala)的核型为2n=2x=58=26m 32sm;细茎橐吾(L.hookeri)的核型为2n=2x=58=30m 26sm 2st;宽戟橐吾(Llatihastata)的核型为2n=2x=58=28m 26sm(2sat) 4st;网脉橐吾(L.dictyoneura)的核型为2n=2x=58=26m 28sm 2st 2t;蹄橐吾(L.hodgsonii)的核型为2n=2x=58=28m 28sm 2t;棉毛橐吾(L.vellerea)的核型为2n=2x=58=22cm 34sm 2t。虽然这7个种的染色体数目相同,2n=58,核型主要是由m和sm染色体构成,但各类的染色体数目在种间有差异。核的对称性高,着丝点端值(T.C)为61.45%-64.96%。除窄头橐吾和鹿蹄橐吾的染色体数与前人报道的相同外,其它5个种的染色体数目和核型为首次报道。  相似文献   

8.
假橐吾属, 中国菊科植物一新属   总被引:1,自引:1,他引:0  
多年生草本,根状茎粗短,有多数纤维状根,茎基部有残存的叶柄。叶互生、纸质,基生叶在花期宿存,具长叶柄,长圆状心形或宽卵状心形,楔状下延成具翅的叶柄,基部扩大,半抱茎,但绝无叶鞘;中部茎叶与下部叶同形,较小,具短叶柄,叶柄具翅,自中部向基部逐渐扩大,基部具叶状卵形抱茎的叶耳。头状花序盘状,在茎端排列成总状;花序梗有2枚小  相似文献   

9.
首次报道了5种国产橐吾属植物的核型,结果如下:东俄洛橐吾(Ligularia tongolensis)核型为2n=58=32m 14sm 12st;侧茎橐吾(L.pleurocaulis)四川稻城居群核型为2n=58=24m 32sm 2st 3~5B,云南中甸居群核型为2n=58=36m 22sm;云南橐吾(L.yunnanensis)核型为2n=58=28m 30sm;叶状鞘橐吾(L.phyllocolea)核型为2n=58=30m 24sm 4st 1B;浅苞橐吾(L.cynthceps)核型为2n=58=24m 34sm。5种橐吾染色体数目都为58。在叶状鞘橐吾和四川稻城产侧茎橐吾中发现有B染色体存在,这在以前对橐吾属及近缘属植物的核型研究中未见报道。  相似文献   

10.
将芥形橐吾(Ligularia brassicoides Hand.-Mazz.)、岷县橐吾(L. ianthochaeta C. C. Chang)和半裂橐吾(L. paradoxa Hand.-Mazz. var. palmatifida S. W. Liu  相似文献   

11.
獐牙菜属植物的起源, 散布和分布区形成   总被引:14,自引:1,他引:14  
本文根据植物类群的系统发育和地理分布统一的原理,讨论了獐牙菜属植物的起源、散布和分 布区的形成。獐牙菜属包括11组16系154种,间断分布在亚洲、欧洲、北美洲和非洲。中国西南部- 喜马拉雅地区汇集了大多数种类、不同演化水平的类群以及形形色色的特有类群,成为该属的多样化 中心和多度中心。该属的原始类群和外类群也集中分布在中国西南山地,极有可能是该属的起源地。该 属的分布区类型中出现了各式的间断分布,根据有该属植物分布的大陆间及大陆与岛屿间分离和连接 的时间推测,该属的起源时间至少不会晚于晚白垩纪,也许更早,可追溯到中白垩纪。通过分类群间亲 缘关系和现代分布分析,显示出该属植物从起源地向周围和一定方向散布,形成了三个主要散布途径。在散布过程中植物本身也发生演化和就地特化,形成新的类群。  相似文献   

12.
The genus Ligularia Cass. is one of the large genera in Compositae-SenecioneaeTussilagininae. In subtrib. Tussilaginae, Ligularia is closely related to, but more advanced than, the genus Farfugium Lindl. It includes six sections, 11 series and 129 species. All the taxa are distributed in Asia with only two species extending to Europe. There are 119 species in E. Asia, Comprising 96 % of the world total. The highest concentration of species in E. Asia occurs in the Hengduan Mountains. In this area there are four section, six series and 67 species, of which 61 species are local endemics; thus 66% of sections, 54.5% of series and about 52 % of species in the world occur in this small area, indicating that it is a major distribution centre for Ligularia. According to character analysis, sect. Corymbosae ser. Calthifoliae with 5 species was considered as the most primitive group in this genus, which has reniform leaves, palmate veins, a few large capitula (arranging in Corymb-like inflorescence), and semispherical involucre etc. The primitive species, L. dentata and L. hodgsonii, are distributed from E. Sichuan to Japan via Hubei, Hunnan, Anhui, Fujian. This distribution pattern is consistent with that of its allied genus, Farfugium. According to the principle of common origin, the ancestors of the two genera appeared most probably in the same area. It was inferred that the area from E. Sichuan of China to Japan was the original area of the genus Ligularia, However, on the basis of geological history and the modern distribution of this genus, the author considers that central China with E. Sichuan might be the primary original area of Ligularia. Its dispersal route was mainly along the mountains of southern margin of Asia, with relatively few members dispersed northea stwards to NE. Asia. The origi-nal time of the genus Ligularia was at least not later than the middle Cretaceous.  相似文献   

13.
杉科植物的起源、演化及其分布   总被引:24,自引:3,他引:24  
本文根据对杉科的系统发育、现代分布和化石分布的研究,结合古地理和古气候资料,讨论了杉科的起源、演化和现代分布格局的成因。杉科基本上是一个亚热带科,我国长江、秦岭以南至华南一带是其现代分布中心。东亚中高纬度的东北地区可能是其起源中心和早期分化中心。起源时间为早侏罗纪或晚三叠纪。杉科植物的各种类型很可能在早白垩纪甚至晚侏罗纪就已分化出来。杉科植物于东亚起源后,在当时劳亚古陆尚未完全解体、气候分带现象尚不甚明显的情况下跨越欧亚大陆散布到北美,并扩散到南半球。自晚白垩纪,白令陆桥和北大西洋陆桥对其在北半球的散布发挥了重要作用。杉科植物目前虽处于衰退状态,但在地质史上却曾经经历过极其繁盛的时代。在中生代中晚期和早第三纪,杉科植物种类繁多,广布于北半球,向北扩散到北极圈内的高纬度地区,是当时的大科。大多数现存属曾分别有过3个或2个分布中心:水松属、落羽杉属和北美红杉属在东亚、北美西部和欧洲;水杉属在东亚和北美西部;柳杉属、杉木属,很可能也包括台湾杉属在东亚和欧洲;巨杉属在欧洲、北美和东亚。在晚白垩纪和第三纪,现存属特别是水松属、落羽杉属、水杉属、北美红杉属和巨杉属,曾是北半球森林植被的重要组成成分。南半球也曾有少量种类,分布亦远较现代普遍。杉科在白垩纪的多样性达到鼎盛,具所有的现代属和大量的化石器官属,但在以后漫长的历史发展过程中,由于地质变迁、气候变化,大量类群绝灭。晚第三纪全球性的气温下降迫使杉科逐渐从高纬度地区撤出。第四纪冰期气候的剧烈恶化使杉科分布区进一步显著退缩至中、低纬度地区,最后在欧洲全部消失,仅在东亚、北美及澳大利亚的少数几个植物 “避难所”中残存下来。现今各属多分布于环太平洋地区极为狭窄的局部范围,在分布区内呈现出孤立或星散的残遗分布式样。杉科现存各属均为古老的孑遗或残遗类群。  相似文献   

14.
山毛榉科植物的起源和地理分布   总被引:13,自引:1,他引:12  
本文根据植物类群系统发育与地理分布统一的原理,讨论了山毛榉科植物起源和地理分布。划定了该科植物的分布区类型。确认东亚和东南亚区为该科植物的分布中心;而马德雷区南部和加勒比区则是该科的次生分布区中心。提出了马来西亚区、东亚区和东南亚区的多数特有种带有古特有植物种性质的观点。认为山毛榉科植物可能起源于中国南部、西南部和中南半岛北部的季节性干旱热带山地森林中,它们起源的时间很可能在晚白垩纪早期。山毛榉科植物进入北美洲的迁移路线主要有两条,即从起源地经欧亚大陆、格陵兰群岛进入北美洲,及经欧亚大陆、白令陆桥进入北美洲。南美洲的山毛榉科植物则是从北美洲经中美洲迁移过去的。山毛榉科植物的现代分布格局是由三方面因素形成的,即大陆漂移形成的海陆相应位置的变化,渐新世以后开始的赤道带的向南迁移和第四纪以来冰期与间冰期多次交替出现,以及山毛榉科植物自身的生物学特性和对于环境的适应能力。在综合各类资料的基础上,讨论了山毛榉科属间的系统演化关系。  相似文献   

15.
藜科植物的起源、分化和地理分布   总被引:27,自引:0,他引:27  
全球藜科植物共约130属1500余种,广泛分布于欧亚大陆、南北美洲、非洲和大洋洲的半干旱及盐碱地区。它基本上是一个温带科,对亚热带和寒温带也有一定的适应性。本文分析了该科包含的1l族的系统位置和分布式样,以及各个属的分布区,提出中亚区是现存藜科植物的分布中心,原始的藜科植物在古地中海的东岸即华夏陆台(或中国的西南部)发生,然后向干旱的古地中海沿岸迁移、分化,产生了环胚亚科主要族的原始类群;起源的时间可能在白垩纪初,冈瓦纳古陆和劳亚古陆进一步解体的时期。文章对其迁移途径及现代分布式样形成的原因进行了讨论。  相似文献   

16.
金粟兰科的起源,演化及其分布   总被引:6,自引:3,他引:6  
本文利用形态解剖,孢粉学及化石资料,讨论了金粟兰科的系统;并对其起源,演化和现代分布格局形成等问题做了合理推测,主要结果如下:(1)Sarcandra和Chloranthus的亲缘关系最接近,而Ascarina和Hedyosmum的系统位置最靠近。Sarcandra是金粟兰科中最原始的属,而Hedyosmum则是最进化的属。(2)金粟兰科可能于白垩纪最早期起源于木质部无导管的,具简单两性虫媒花的祖  相似文献   

17.
罂粟科植物的分类,进化与分布   总被引:4,自引:1,他引:4  
庄璇 《云南植物研究》1993,15(2):137-148
罂粟科有38属约700种,作者通过对科内各属的研究,根据其主要器官(雌蕊、雄蕊,花被、果和种子)的进化趋势,重新排列科内的分类系统,在3个亚科下,包括8个亚族。在此基础上,讨论各属可能的演化关系,分析它们的分布规律,最后探讨本科的起源。  相似文献   

18.
木兰科(Magnoliaceae)的起源、进化和地理分布   总被引:13,自引:0,他引:13  
木兰科为亚洲-美洲间断分布科,全世界有15属,246种,主要分布于亚洲东南部的热带、亚热带地区,从喜马拉雅至日本,向南达新几内亚及新不列颠;少数种类分布于北美东南部、中美至南美巴西.中国有11属,约99种.木兰科的现代分布中心在东亚-东南亚地区.根据木兰科的化石记录、系统发育和现代分布,推测其起源时间为早白垩纪,甚至更早.起源地可能在中国的西南地区,并由此向外辐射,向东经日本、俄罗斯远东地区经白令陆桥进入北美;向西经西亚、欧洲,通过格陵兰进入北美,然后到达南美;向南经印度支那、马来西亚,直至新几内亚.东亚-北美间断分布的形成是受第四纪冰期的影响;南美的木兰科是从北美迁移而来.  相似文献   

19.
木兰科(Magnoliaceae)的起源、进化和地理分布   总被引:30,自引:1,他引:30  
木兰科为亚洲-美洲间断分布科,全世界有15属,246种,主要分布于亚洲东南部的热带、亚热带地区,从喜马拉雅至日本,向南达新几内亚及新不列颠;少数种类分布于北美东南部、中美至南美巴西.中国有11属,约99种.木兰科的现代分布中心在东亚-东南亚地区.根据木兰科的化石记录、系统发育和现代分布,推测其起源时间为早白垩纪,甚至更早.起源地可能在中国的西南地区,并由此向外辐射,向东经日本、俄罗斯远东地区经白令陆桥进入北美;向西经西亚、欧洲,通过格陵兰进入北美,然后到达南美;向南经印度支那、马来西亚,直至新几内亚.东亚-北美间断分布的形成是受第四纪冰期的影响;南美的木兰科是从北美迁移而来.  相似文献   

20.
The genus Swertia is one of the large genera in Gentianaceae, including 154 species, 16 series and 11 sections. It is disjunctly distributed in Europe, Asia, Africa and N. America, but entirely absent from Oceania and S. America. According to Takhtajan’s (1978) regionalization of the world flora, Swertia is found in 14 regions. Eastern Asiatic region with 86 species, of which 58 are local endemics, 13 series and 9 sections, ranks the first among all the regions. The highest concentration of the taxa and endemics in Eastern Asiatic region occurs in SW China-Himalayan area (Sikang-Yunnan P. , W. Sichuan, W. Yunnan-Guichou Plateau of China and NE. Burma, N. Burmense P. , E. Himalayan P. and Khasi-Manipur P. ). In this area there are 74 species (48 endemics), 12 series, and 9 sections; thus about half species of the world total, three quarters of series and 82% of sections occur in this small area. Besides, the taxa at different evolutionary stages in Swertia also survive here. It is an indication that SW. China-Himalayan area is a major distribution centre of the genus Swertia. In addition, Sudan-Zambezian Region in Africa, with 22 species, 4 series and 2 sections, is a second distribution centre. The primitive type of the genus Swertia is Sect. Rugosa which consists of 2 series and 23 species. It is highly centred in the mountains of SW. China (Yunnan, Sichuan, Guizhou and SE. Xizang) where 2 series and 16 species occur. Among them 15 species of Ser. Rugosae were considered as the most primitive groups in this genus. From our study, the outgroup of Swertia is the genus Latouchea Frahch. , which is distributed in Yunnan, Sichuan, Guizhou, Hunan, Guangdong, Guangxi and Fujian. The two groups overlap in distribution in SW. China. According to the principle of common origin, the ancestor of two genera ap peared most probably in this overlapping area. It was inferred that SW. China Was the birth-place of the genus Swertia. Four sections of Swertia have different disjunct distribution patterns: Sect. Ophelia is of Tropic Asia, Africa and Madagascar disjunct distribution; sect. Swertia is of north temperate distribution; sect. Spinosisemina is in Tropical Asia (Trop. India to S. China and Philipines); sect. Platynema also is in Tropical Asia (Java, Sumatra, Himalayas to SW. China). These disjunct patterns indicate that the Swertia floras between the continents or between continent and islands have a connection with each other. From paleogeographical analysis, Swertia plants dispersed to Madagascar before the Late Cretaceous, to SE. Asian Islands in the Pleistocene, to North America in the Miocene. The distribution of Swertia in Madagascar might be later than that in Asia. Therefore the origin time of the genus Swertia was at least not later than the Late Cretaceous, and might be back to the Mid-Cretaceous. The genus Swertia first fully developed and differentiated, forming some taxa at different evolutionary stages (Rugosa, Swertia, Poephila, Ophelia and Platynema etc. ) in the original area, and these taxa quickly dispersed in certain directions during the Late Cretaceous-Middle Tertiary when the global climate was warm and no much change. There seem to be three main dispersal routes from the origin area to different continents; (1) The westward route i. e. from SW. China, along the Himalayas area to Kashmir, Pakistan, Afghanistan and Iran, and then southwestwards into Africa throuth Arabia. Four sections (Poephila, Macranthos, Kingdon-Wardia and Ophelia) took this dispersal route. Most species of sect. Ophelia dispersed along this route, but a few along southern route and north ern route. Sect. Ophelia greatly differentiated in Africa and the African endemic sectionSect. Montana was derived from it. The two sections form there a second distribution center of Swertia. (2) The southward route, i. e. towards S. India through the Himalayas, and towards SE. Asian islands through C. and S. China, Indo-China. Along this dispersal route sect. Platynema, Sect. Spinosisemina and a few species of Sect. Ophelia dispersed; (3) The northward rout, i. e. northwards across N. China, C. Asia to a high latitude of Euasia, and also through E. Asia into N. America. The following groups took this route: sect. Rugosa, sect. Swertia, sect. Frasera, sect. Heteranthos and sect. Ophelia ser. Dichotomae. Therefore, it seems that the genus Swertia originated in SW. China and then dispersed from there to N. and S. Asia, Africa, Europe and North America and formed the moderndistribution pattern of this genus.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号