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1.
DNA水平上的植物系统学研究进展   总被引:4,自引:0,他引:4  
分子钟假说为在分子水平上研究生物进化提供了理论基础,分子系统学已成为当前生物学领域中的热门课题,并取得了许多引人注目的进展。本方要以高等植物为对象,从核DNA,叶绿体DNA和线粒体DNA三方面对植物分子系统学进行了综述。  相似文献   

2.
真菌分子系统学以分子生物学、遗传学和生物信息学为手段,以分子水平对真菌进行种属识别,与传统的表型分类系统相比,更为可靠、高效,极大地推动了真菌分类学的发展。因此,真菌分类学正处于一个划时代的转变时期,即由表型分类向基因型分类的转变,以形态学为基础的种属概念向以分子系统学为基础的种属概念转变。综合论述了分子系统学在真菌分类和命名中的应用,并介绍近年来真菌分类和命名方面的变化和进展,供国内科研和临床工作者参考。  相似文献   

3.
史立群 《化石》1997,(3):28-30
分支系统学简介史立群分支系统学(Cladistics)(也有人译为分支分类学、支序学等等),是推测生物体之间相互关系的一种特殊方法。象其他方法一样,它有着一套自身的假设、程式和局限性。它于1950年由德国昆虫学家和分类学家W.Hennig首次提出并兴...  相似文献   

4.
关于我国植物系统学研究的一些感想和建议王文采 (中国科学院植物研究所系统与进化植物学重点实验室 北京 100093) Miscellaneous notes on plant systematics in China WANG Wen-Tsai (Laboratory of Systematic and Evolutionary Botany, Institute of Botany, the Chinese Academy of Sciences, Beijing 100093, China)  相似文献   

5.
昆虫标本馆建设与昆虫系统学的未来   总被引:6,自引:0,他引:6  
昆虫标本馆是昆虫标本的保藏、研究和科学教育的实体,代表国家或者区域水平,致力于研究昆虫多样性、揭示昆虫进化规律,为国民经济建设持续发展服务。昆虫系统学研究是昆虫标本馆研究人员的主要任务,它的发展与昆虫标本馆的建设唇齿相依。本文阐述了昆虫标本馆的功能与作用,建设昆虫标本馆的重要性和迫切性;展望了昆虫系统学的未来以及昆虫系统学发展的机遇。  相似文献   

6.
分支系统学简介   总被引:1,自引:0,他引:1  
分支系统学简介樊晋江(浙江省医学科学院寄生虫病研究所杭州310013),关键词分支系统学,分支分类,系统发育1950年诞生的分支系统学,现在已经发展成为探索生物系统发育的有效工具之一。分支系统学与现代计算机技术的结合形成了新的分支学科─—数值分支系统...  相似文献   

7.
龟鳖目系统学系统概况   总被引:2,自引:0,他引:2  
本文对龟鳖目形态学水平,染色体水平及分子水平的系统学研究进行了综述,并讨论了亚洲龟鳖类的系统学和分类学问题。  相似文献   

8.
《植物分类学报》2005,43(2):191-191
"中国植物系统学百年回顾"学术交流会于2005年2月25日至27日在深圳仙湖植物园召开.会议由仙湖植物园和<植物分类学报>编委会联合主办.来自国内外植物系统学研究领域的专家学者共90余人参加了此次会议.他们共同回顾了中国植物系统学研究近百年来所取得的卓越成就,展望了未来的光辉前景.  相似文献   

9.
三白划科花部发育及其系统学意义   总被引:1,自引:0,他引:1  
  相似文献   

10.
传统的植物学理论中, 被子植物雌蕊的基本单位心皮被认为是变态的叶(即大孢子叶)通过纵向对折和内卷演化而来。该理论造成了被子植物和裸子植物之间不可逾越的鸿沟。近年来提出的一统理论认为被子植物的心皮由长胚珠的枝和包裹这个枝的叶共同组成, 从而弥合了被子植物与裸子植物之间的鸿沟。最近, 当代植物学界两大权威人物Peter R. Crane和Peter K. Endress分别撰文, 发表了不同于传统理论的观点。Endress认为, 心皮由胚珠和叶性器官组成; 而Crane认为, 所有的胚珠都长在枝上。结合二者的结论, 不难得出“心皮实际上等同于一个长胚珠的枝加上一个叶”的论断。这在某种意义上等于认同了一统理论的观点。两位权威人物观点的转变预示着植物学理论将很快发生根本性的转变。该文向国内植物学同行通报这一最新动态, 以期让我国学者能够了解最新理论。  相似文献   

11.
Subfam. Panicoideae consists of 230 genera and 3000 species, about 1/3 of the total number of Gramineae. The evolution in Gramineae (Poaceae) is considered to have been proceeding in the direction of simplification. Three major lineages in Panicoideae are recognized based on analysis of characters, geographical distribution and ecological preferences. They are represented respectively by three supertribes i.e. Panicatae, Andropogonatae and Maydatae. The first supertribe has well-developed florets, fertile lemma indurate, but is awnless and thus is the primitive group in the subfamily. In the second supertribe spikelets are well-developed, the lower glume is larger than the florets and embraces them, the florets are awned. Particularly significant is the evolution of spikelets from solitary to paired, from the two spikelets of each pair both bisexual and alike in form to heterogamous pair of spikelets in which the sessile one is fertile and the pedicelled one sterile and further to homogamous pair of spikelets at base of inflorescence. In this lineage occurs an inflorescence protected by a large sheathing bract. It is the most flourishing by developed evolutionary branch. In the third supertribe raches are developed, thick, inflorescences have become pillar-shaped with spikelets sunken in the raches. The reduction of spikelets from bisexual to unisexual has taken place and they occur on separte inflorescenes, bringing about subsequent sexual differentiation of inflorescences. Raches have also evolved from solitary to united. The supertribe Maydatae is likely to be one of the most advanced group in Gramineae. Subfam. Panicoideae occurs in the tropics and subtropics, and these three supertribes have apparently followed three lines of development under different environmental conditions. The supertribe Panicatae adapts to hot moist conditions, the supertribe Andropogonatae adapts to a monsoon climate, occurring in savannas, the supertribe Maydatae occurs in monsoon moist conditions.  相似文献   

12.
The flowers of the representative species of 33 tribes and 174 genera were investigated for the purpose of Gramineae systematics. Discussed in this paper are ten important flower characters, 6 of which are of the pistil, two of the androecium and two of the lodicule. The morphology of lodicules is of particularly great value in systematics, it consisting of nine forms: membranous-flattend, tongue-shaped, chaffy-peltate, hooded or helmet-shaped, spade-like, longitudinally folded, cucullate, top-shaped and funnel-thaped. Its numbers per flower may be: numerous, triple, dual, single and absent. On the basis of these ten characters, three major types and seven subtypes of the flowers of Gramineae may be recognized: Bambusoid (including True Bambusoid, Oryzoid, Arundinoid, Stipoid), pooid (with Subtype Pooid only) and Panicoid (including Eragrostoid, True Panicoid). As a result, The major groups corresponding to the flower basic types agree wih those divided according to the basic types of seedlings and caryopses. They are seven subfamilies: Banbusoideae, Oryzoideae, Arandinoi deae, Stipoideae, Pooideae, Eragrostoideae and Panicoideae.  相似文献   

13.
The morphological and anatomical characteristics of bamboo fruits of 39 species in 21 genera have been surveyed. The results showed that characters as the shape, the middle cross section, the morphology of pericarp, rostrum and embryo, the presence or absence of ventral groove and embryotega, and the thickness of aleurone layer of fruits were the important features in identifying different genera, and also in studying systematics and evolution of the bamboos. All the bamboo fruits examined herewith could be considered as caryopses, and they could be subdivided into four types viz. typical, bacoid, nucoid and seminucoid type. Type A,typical,as most grass fruits, with thin pericarp throughout or thickened only at apex, ventral groove (hilum) and embryotega, was found in the majority of bamboos, such as Fargesia and Arundinaria. Type B, bacoid, with thick and fleshy pericarp, was found in nine genera: Melocanna, Dicochloa, Ochlandra,Olrneca, Melocalarnus, Chirnonobarnbusa ,Qiongzhuea, Ferrocalamus and Alvirnia. Type C, nucoid, with hard pericarp, was found so far only in Dendrocalamus and Cephalostachyurn. Type D,semi-nucoid, the intermediate type between type A and C, with pericarp, as in type A, in the dorsum and pericarp, as in type C in the ventrum was found in Sinocalarnus, PhyUostachys and Thyrsostachys. Bacoid may be the primitive type, from which nueoid may have evolved. Semi-nucoid may have evolved from nucoid. Typical type may be advanced and have evolved from bocoid or semi-nucoid. The primitive fruits of bamboos may have characteristics such as follows: globose or spheroidal in shape, round middle cross section; thick and fleshy pericarp throughout, less differentiated, presence of vascular bundle; absence of ventral groove (hilum) and embryotega; aleurone layer composed of a number of cell layers; large and curved'or folded embryo. Bamboos with such a fruit have iterauctant inflorescences except Ferrocalamus.  相似文献   

14.
竹亚科系统学和生物地理学研究进展及存在的问题   总被引:8,自引:1,他引:8  
郭振华  李德铢 《云南植物研究》2002,24(4):431-438,462
对近年来在竹亚科作为一个单系类群的界定、其系统位置的确定、内部系统演化趋势以及地理分布和起源方面研究所取得的进展进行了评述。竹亚科作为一个单系类群仅包括了木本的竹族(Bambuseae)和一个草本的莪利竹族(Olyreae),其中莪利竹族分布在新几内亚的伊里安竹(Buergersiochloa)处于Olyreae最基部。禾本科12个亚科中除了3个亚科为基部类群以外,其余9个亚科分成PACCAD(包括黍亚科,狭义的芦竹亚科,广义的虎尾草亚科,假淡竹叶亚科,三芒草亚科和扁芒草亚科)和BOP单系分支(包括竹亚科,稻亚科和早熟禾亚科)。在BOP支中,竹亚科与早熟禾亚科相近缘,共同组成稻亚科的姐妹群。竹亚科分成草本和木本两个单系类群,木本竹子又分成热带和温带支系,热带支系进一步分成新世界热带和旧世界热带两个单系类群。从现有的化石证据和基部类群的地理分布推断,竹亚科很可能起源于晚白垩纪的冈瓦纳古陆。最后,本文就竹亚科研究尚存在的问题做了初步探讨。  相似文献   

15.
齿蟾属(Oreolalax)为中国特有属,主要分布在我国西南地区。本文对该属的系统学研究进行了综述,包括属的建立与物种组成、地理分布特征、细胞分类学、系统发育研究历史,以及尚需研究或进一步研究的问题。  相似文献   

16.
Examinations were made on the morphology of caryopses of 324 grass species representing over 109 genera and 31 tribes. The evolutionary tendency of the important characteristics and the relation with distribution areas and habitats are discussed. According to the shape of caryopses, the morphology of ventral faces and hilum, the proportion of embryos to caryopses in size, the existence or absence of the top fine hairs, the persistence or shedding of styles, the size of fruits and especially the outline of the middle cross section, etc., the caryopses may be divided into three major types and seven subtypes: Bambusoid (including True Bambusoid, Arundinoid, Oryzoid, Stipoid), Panicoid (including True Panicoid, Eragrostoid) and Pooid (including the Subtype Pooid only). In this study, the different types of caryopses are found to be correlated with the characteristics of embryos, seedlings, habits and chromosomes, and on these grounds, the genera of the Gramineae are grouped into seven corresponding subfamilies: Bambusoideae, Oryzoideae, Arundinoideae, Stipoideae, Eragrostoideae, Panicoideae and Pooideae.  相似文献   

17.
郭鹏 《四川动物》2005,24(3):428-431
2004年以来,广义竹叶青蛇的系统学研究取得了较大的进展。本文对这近一年来的最新进展进行概括和报道。  相似文献   

18.
简要介绍了禾本科虎尾草亚科的分类历史。考察虎尾草亚科属上阶元的变化过程,概括不同时期该亚科分类学研究的进展及分类原则,对3种研究方法的不足进行评价。自1990年《中国植物志》第10卷第1分册出版以来,对中国虎尾草亚科植物属种水平的系统变化进行了说明。为了更好地理解虎尾草亚科的系统发育关系,指出了虎尾草亚科没有解决的问题及今后的研究方向。  相似文献   

19.
适应辐射类群穇属的系统学研究进展   总被引:1,自引:1,他引:0  
综合花序拓扑学、比较形态学、分子系统发育、细胞遗传学等资料,对适应辐射类群穆属(Eleusine Gaertn.)的系统学研究进展进行了述评.穆属系统位置--Eleusiinae亚族成员得到分子系统发育证据的支持.该属具有3种花序类型、7个基因组类型、多倍体均由二倍体杂交起源、C4植物高度适应半湿润-半干旱镶嵌气候等特征.据可靠化石记载和现代地理分布推断,穆属很可能起源于东非,时间是晚中新世,而适应辐射则发生在上新世-中新世间隔.总的来说,分子系统发育、细胞遗传学、古地质、古气候数据的整合研究能够为穆属多倍体起源和谱系多样化历史提供令人信服的证据.  相似文献   

20.
Data on the occurrence of free and conjugated gibberellins in different tribes of Gramineae are compiled and discussed with regard to their biosynthetic pathways. From the gibberellins detected so far the functioning of both the early 13-hydroxylation and the non-3,13-hydroxylation pathway of GA biosynthesis in gramineous plants can be deduced and the discovery of further gibberellin conjugates may be expected.  相似文献   

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