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1.
槭属(Acer L.)属槭树科(Aceraceae),200种,分布于亚、欧、北美和非洲北缘。本文研究了槭属的系统演化、地理分布、起源与扩散。认为:(1)槭树科与无患于科关系密切,槭属是槭树科2属中较进化的类群。(2)在原始而典型的槭属植物的基础上,槭属沿花的各部减少,有的器官甚至向完全退化的方向演化,但也有少数向增加数目的方向特化。(3)讨论了槭属4亚属23组的演化趋势,并绘制出其系统演化图。(4)槭属起源于侏罗纪的中国四川东部、湖北、湖南及其邻近地区,并向西、东北和南方扩散而进入西亚、欧洲、非洲北缘、北美洲和马来半岛至印尼。  相似文献   

2.
翅果形态及其在槭树科分类与演化上的意义   总被引:12,自引:0,他引:12  
徐廷志   《广西植物》1996,16(2):109-122
槭树科(Aceraceae)是北温带分布的科,含2属,全世界约200种,中国是槭树科植物的现代分布中心。对槭树科翅果的专门研究尚未见报道。本文1、引用一套槭属翅果形态学术语;2、观察并描述75种械属植物的翅果;3、研究槭属16个组的翅果的17个可比性状,根据分枝系统分析法得出槭属各组的演化关系及趋势,这趋势与依据其花、叶等性状得出的演化关系基本上是一致的。  相似文献   

3.
东北槭属的种子表皮雕纹及其在分类上的意义   总被引:1,自引:0,他引:1  
杜凤国  张玉钧 《植物研究》1998,18(3):361-365
借助于扫描电子显微镜,对我国东北地区槭属(Ace)的11种变种的种皮雕纹进行了扫描观察,并拍制了电镜照片。从种皮的雕纹类型看,槭树属的种皮可以概括为四种类型:(1)嵌合型;(2)穴状条纹型;(3)条纹型;(4)网格型;雕纹的形态也支持了色木槭和元宝械作为两个独立种的处理意见;以及小果紫花槭作为紫花槭(Acerpseudo-siebolidianum(Pax.)Kom)的种下等级变种(var.kor  相似文献   

4.
中国伞形科特有属的核型演化及地理分布   总被引:17,自引:0,他引:17  
首次报道了我国伞形科10个特有属9种1变种14个居群的核型,染色体基数分别为n=6,8,10和11,核型类型有2A,3A和4A三种类型。根据各属的核型演化水平并结合其花粉形态,初步确定东俄芹属(Tongoloa)、环根芹属(Cyclorhiza)、明党参属(Changium)和川明参属(Chuaminshen)是古特有属,其余各属则处于中等或较高的演化水平上。同时初步讨论了各特有属在伞形科分类系统中的核型演化关系并比较了各主要分布区之间核型的演化水平,发现横断山地区不仅特有属数目高,染色体基数变化大,且集中了核型较为原始和演化程度很高的类群,极可能是伞形科特有属的起源和分化中心。  相似文献   

5.
槭树科花粉形态的研究   总被引:8,自引:0,他引:8  
用光学显微镜及扫描电子显微对槭树科2属10种1亚种4变种的花粉形态进行了研究。结果表明,金钱属的花粉为3孔沟,槭树属的花粉分为3沟和3孔沟两大类型。研究结果澄清了前人一些片面的看法,并从花粉形态特征探讨了该科各属及类型间的亲缘关系。  相似文献   

6.
稀有濒危植物珊瑚菜的染色体特征及其演化地位   总被引:2,自引:1,他引:1  
刘启新  惠红  刘梦华   《广西植物》1999,19(4):344-348
首次分析了珊瑚菜( Glehnia littoralis) 根尖体细胞染色体组型。其核型公式为2 n = 22= 18M + 4Sm (2Sat) , 核型不对称性属于2A 型。据此讨论了该属在我国伞形科稀有濒危单型属和当归亚族中的演化地位。  相似文献   

7.
槭树科的地理分布   总被引:35,自引:3,他引:35  
槭树科是北温带分布的科,2属202种。本文论述了本科的植物生态学、科的地理分布、槭属的亚属和组系统位置及其分布式样和种的分布,以及对古特有种、新特有种的分析,认为北温带分布的槭树科是热带起源的,其分布中心和祖型都在中国亚热带山地-横断山区连同湖北、湖南和四川东部。在这里,特别在横断山区槭树科种类丰富、分布集中,古特有和新特有成分均多,分化明显,是新老区的结合及分布中心,而且很有可能是槭树科的起源地  相似文献   

8.
云南槭树红叶观赏植物资源开发利用   总被引:2,自引:0,他引:2  
云南,誉称“植物王国”。在槭树资源的多样性、丰富性上植物的“王国”性也是一个极佳的例证。槭树,属槭树科(Accraceae)槭属(acer L.),英文名Maple,全世界约200种,分布于亚洲、欧洲、北美洲,有一种分布于非洲北缘。我国是世界槭树的分布中心,分布的种类最多。到目前为此,已知有164种(包括作者发表的6个新种),占全世界槭属植物种类的75%以上。主产长江流域及其以南各省,全国各地均有分布。我国各省区分布械树种类是:云南59种,四川44种,湖北30种,广西29种,陕西、贵州各28种,浙江25种,安徽23种,甘  相似文献   

9.
槭树与园林   总被引:1,自引:0,他引:1  
中国植树种质资源丰富槭树是槭树科槭属树种的泛称,其中一些种又被俗称为枫树。全世界的槭属植物有199种,分布于亚洲、欧洲、北美洲和非洲北缘。中国是世界上槭树种类最多的国家,目前已知有151种,全国各地均有分布,主产于长江流域及其以南各省区。其中云南种类最多,产59种;四川次之,有44种;湖北有30种;广西29种……宁夏、新疆、青海最少,均仅有1种。据笔者调查,我国长江流域的槭树在100种以上,占世界种类的一半,是世界槭树的现代分布中心。从海拔高度来看,我国槭树的分布非常广泛,从海滨到4000米的高寒山区均有。在我国云南…  相似文献   

10.
使君子科风车子亚科核糖体DNAITS区序列分析及系统学意义   总被引:1,自引:0,他引:1  
使君子科(Combretaceae)主要分布于热带非洲和亚洲,美洲和澳洲也有少量分布。全世界有约20属,近 500多种(Exell & Stace, 1996) 。我国有 6属约 25种,均分布于长江以南各省区,主产云南及海南岛(徐廷志,1984)。其中,除使君子属(Quisqualis)仅有2种外,桃仁树属(Terminalia)和风车子属(Combretum)是全科最大的两属,榆绿木属(Anogeissus)在我国只有一种,它是我国北热带季节性雨林中的建群树种之一(傅立国,1992),萼翅藤…  相似文献   

11.
The spread of the western flower thrips Frankliniella occidentalis (Pergande)   总被引:17,自引:0,他引:17  
Abstract 1 Since the late 1970s, the western flower thrips has spread from its original distribution in western North America to become a major worldwide crop pest. 2 A wide range of data sources have been used to map the original distribution in the U.S.A. and Canada, and the progress of the spread in the U.S.A., Canada, Europe, northern Africa and Australia. 3 The possible reasons for the start of the spread are discussed. The most likely reason is that intensive insecticide use in horticulture in the 1970s and 1980s selected an insecticide resistant strain or strains. These then established in glasshouses across North America and spread from there to Europe, Asia, Africa and Australia. 4 The international spread of the western flower thrips occurred predominantly by the movement of horticultural material, such as cuttings, seedlings and potted plants. Within Europe, an outward spread from the original outbreak in the Netherlands is discernible. The speed of spread was 229 ± 20 km/year. 5 The spread has not been restricted to glasshouses. The western flower thrips has established outdoors in areas with milder winters; for example, across the southern U.S.A., southern Europe and Australia. It also overwinters in some regions with colder winters. 6 Polyphagous phytophagous thrips have many factors predisposing them to become worldwide crop pests, particularly in glasshouses. Some other species that might spread in a similar way to the western flower thrips are listed.  相似文献   

12.
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   

13.
槭树科花粉形态及其系统学意义   总被引:9,自引:1,他引:9  
报道了槭树科(Aceraceae)槭属21组33种和金钱槭属2种植物的花粉形态。本科花粉近球形至长球形,极面观为三裂圆形。从花粉萌发孔类型看,金钱槭属Dipteronia具三孔沟,槭属(Acer)除4组具三孔沟外,其余均为三沟。从花粉外壁纹饰看,金钱槭属2个种和槭属的大多数种为条纹状,罕为细条纹-拟网状和皱波状。通过花粉形态分析,并结合其它方向的证据,我们认为:(1)Sect.Palmata,Sect.Spicata和Sect.Microcarpa可能是槭属中与金钱槭属关系最密切的类群;(2)A.distalum和A.nipponicum代表了近缘的两个单种组;(3)A.pseudoplatanus不同于Sect.Acer的其它4个种而与A.saccharum可能存在更为密切的关系;(4)Sect.Carpinifolia(细条纹-拟网状外壁纹饰)和Sect.Negundo(皱波状外壁纹饰)则可能代表了槭属中最特化的类群;(5)按槭树科花粉三孔沟到三沟的演化规律,Dipteronia较Acer原始。  相似文献   

14.
Pollinator shifts are often related to speciation in angiosperms, and the relationship between them has been discussed in several plant taxa. Although limited information on plants pollinated by non-flying mammals in Central and South America and Africa is available, related research has not been conducted in Asia. Herein, I summarize the available knowledge of pollination in Asian Mucuna (Fabaceae), a genus mainly distributed in the tropics, and discuss the evolution of plants pollinated by non-flying mammals in Asia. Nineteen pollinator species have been recorded and pollination systems have been categorized into four types. An examination of the relationship between Mucuna species and their pollinators from the lineage perspective revealed that all species in Mucuna, subgenus Macrocarpa, which are distributed in Asia, are pollinated exclusively by non-flying mammals. Additionally, plants pollinated by non-flying mammals were found to have diverged from bat-pollinated and non-flying mammal-pollinated plants, while plants pollinated by non-flying mammals have evolved multiple times. This is a unique example of evolutionary transition. I hypothesize that the diversification of squirrel species in tropical Asia may have led to the speciation and diversification of Mucuna in Asia. Furthermore, the behavioural and ecological characteristics of bats and birds in Asia differ from the characteristics of those in other regions, implying that Asian Mucuna species do not rely on bat or bird pollinators. The adaptation of floral characteristics to pollinators is not well understood in Asia. Mammal-pollinated plants in Asia may have evolved differently from those in other regions and have unique pollination systems.  相似文献   

15.
姜科植物地理   总被引:9,自引:1,他引:9  
本文讨论了姜科的分类系统、起源、进化和地理分布.姜科为一还热带分布科,按Burtt[8]的系统分2亚科4族.全世界有52属,约1377种,其中姜亚科含48属,1268种.主要分布于热带亚洲.其现代分布中心在印度-马来西亚。闭鞘姜亚科含4属,109种,主要分布于热带美洲及非洲。本文在化石资料及现代分布资料的基础上,讨论了姜科的早期分化时间、地点及现代分布格局形成。化石记录表明.欧洲、北美及印度的白垩纪、早第三纪均发现过姜科的化石,据此姜科植物的起源时间应不晚于早白垩纪。姜亚科的早期分化中心推论在劳亚古陆的南部.欧洲和北美没有现代姜科的分布是因为第三纪冰期的影响.而亚洲热带地区现代姜科植物繁盛是因为气候适宜.且相对稳定所致.南美的姜亚科种类应是由非洲传人.而大洋洲的姜亚科种类则是由马来西亚传入.闭鞘姜亚科的早期分化中心推论在西冈瓦纳古陆.亚洲及大洋洲的闭鞘姜亚科的种类应是随印度板块飘向亚洲时传入。中国姜科植物有22属.209种(占全世界属的42%.种的15%).主要分布于马来西亚亚区(占全国属的90%).其次为中国喜马拉雅亚区(占全国属的68%)。最少为中国-日本亚区(占全国属的45%)。统计数字表明.马来西亚  相似文献   

16.
在回顾白刺属研究历史的基础上,根据白刺属种间染色体倍数特征并结合形态学、生物地理学等方面的研究文献,提出新的白刺属种间分类系统:二倍体组(2n= 2X=24) 和四倍体组 (2n=4X=48)。多倍化(2X→4X)是白刺属内种间进化的基本特征。白刺属的起源中心可能是古地中海沿岸地区;中亚及我国西北地区是白刺属的现代分布中心。并指出将该属作为模式系统开展荒漠植物分子生态学研究的前景。  相似文献   

17.
论无心菜属的地理分布   总被引:2,自引:0,他引:2  
全世界无心菜属植物有306种,隶属10亚属24组,主要分布于欧、亚、美三洲和北非,基本上是北温带分布属。文章分析了亚属的系统位置及其分布式样。地中海区到西亚亚区和中亚亚区的西北部是其分布区中心,也可能是它的起源地,中国横断山脉到青藏高原是其次生分布中心。起源时间至少应该追溯到白垩纪中期。最后,讨论了它的散布途径和现代分布式样的形成及其原因。  相似文献   

18.
Phytochemistry Reviews - Aromatic grasses of Cymbopogon (Poaceae) are a known genus of medicinal plants used in traditional medicine by the native people of America, Asia, and Africa. Due to large...  相似文献   

19.
本文讨论了贵州槭树科植物区系与分布。通过种类数量统计分析得出:1.我国西南、华中与华南尤其是西南很可能就是槭树科的起源地带;2.贵州槭树科植物与广西、湖南的关系较其它省区更亲近,它反映了贵州与这些地区在地史时期槭树科植物演化、地理联系的历史渊源。根据贵州所产械树科37种7变种1亚种的分布区比较分析、归类,将它们划分为2种分布式7种区系地理成分:1.中国-日本分布式:(1)华夏型,(2)贵州特有型,(3)黔桂型(相当于滇黔桂型),(4)华南型,(5)华中型,2.中国-喜马拉雅分布式:(1)云贵高原型(相当于云南高原型),(2)横断山脉型。这7种成分以华夏、贵州特有与黔桂3种类型占主体,占省产总数的64.4%。最后,本文分析了槭树科植物在贵州的分布特征:1.械树科在贵州主要分布于黔东南、黔东北与黔南;2.地理(水平)的与垂直的分布替代性非常明显。  相似文献   

20.
Barbeya, a monotypic genus of dioecious, arborescent dicotyledonous plants from northeast Africa and adjacent Arabia, is usually regarded as having affinities within the Urticales. It is placed either in the Ulmaceae or segregated as a closely related, monotypic family. Leaves are opposite, exstipulate, and vascularized by a single, crescent-shaped trace from a unilacunar node. Wood anatomy indicates specialization at about the same level as other Urticales. Sieve tube elements of the secondary phloem exhibit highly oblique, compound sieve plates which indicate a low level of evolutionary advancement. The vascularity of the flower is described and compared with other Urticales. Pollen is tricolporate. The relationships of the genus to Moraceae, Ulmaceae, Urticaceae, and Eucommiaceae are discussed. The totality of anatomical and morphological evidence supports the retention of the family Barbeyaceae.  相似文献   

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