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1.
Paphiopedilum malipoense S. C. Chen et Tsi is a very interesting new species with its flower similar to that of Cypripedium, especially section Cypripedium. It belongs to subgenus Brachypetalum, the most primitive group of Paphiopedilum, but differs from its allied species in hgniva elliptic-lanceolate sepal with cuspidately acuminate apex, rather narrow petals and horizontal lip, which are of common occurrence in many cypripediums, but very rare in paphiopedilums. Apparently, this is an intermediate form, or a link, between Paphiopedilum and Cypripedium, but it does not seem to arise from hybridization between them, because no Cypripedium has been found wherever Paphiopedilum occurs. The new species is distributed in southeastern Yunnan of China. In this area, as well as in river valleys of western Yunnan or the Hengduan Mountains, there have been four species of the same genus reported before. As we know, the Hengduan Mountains and their adjacent areas are rich in Cypripedium. The differentiation of the genus there is remarkable. All five sections it contains occur there and three of them are quite distinctive. For example, the general appearance of the section Bracleosa is dissimilar to that of any other cypripediums, but closely resembles that of Listera. It appears that the difference between sect. Bracteosa of Cypripedium and sect. Brachypetalum of Paphiopedilum is not necessarily wider than that between sect. Bracteosa and sect. Cypripedium of the same genus. Apparently, it is reasonable to consider Paphiopedilum to be an evolutional branch of Cypripedium extending into tropical area, with its primitive group (subgenus Brachypetalum) still remaining in its northern fringe area. This primitive subgenus has eight species, distributed from western Yunnan to the Malay Peninsula. Five of them, including the intermediate and primitive form published here, are found in the hilly land of southeastern Yunnan and the river valleys of western Yunnan. All these facts suggest its area of origin: the river valleys of the Hengduan Mountains and the lower hilly land contiguous to the southof them.  相似文献   

2.
徐可  王涛  张毓 《生物资源》2020,42(1):43-48
兰科杓兰属(Cypripedium)植物主要分布于东亚、北美等温带地区和亚热带山地。杓兰不仅具有极高的观赏价值,而且其经济价值和科研价值也越来越受到人们的重视。近年来对杓兰属植物人工繁殖的相关研究不断深入,主要集中于种子的非共生萌发等方面。本文对濒危兰科杓兰属植物进行了简要介绍,并就其种子非共生萌发研究从种子成熟度、预处理和有机添加物的作用、培养基的配置等方面进行综述,为目标杓兰种类的非共生萌发试验方案的制定奠定基础,将有助于温带/高山兰科植物保育研究的发展。  相似文献   

3.
The hickory genus (Carya) contains ca. 17 species distributed in subtropical and tropical regions of eastern Asia and subtropical to temperate regions of eastern North America. Previously, the phylogenetic relationships between eastern Asian and eastern North American species of Carya were not fully confirmed even with an extensive sampling, biogeographic and diversification patterns had thus never been investigated in a phylogenetic context. We sampled 17 species of Carya and 15 species representing all other genera of the Juglandaceae as outgroups, with eight nuclear and plastid loci to reconstruct the phylogeny of Carya. The phylogenetic positions of seven extinct genera of the Juglandaceae were inferred using morphological characters and the molecular phylogeny as a backbone constraint. Divergence times within Carya were estimated with relaxed Bayesian dating. Biogeographic analyses were performed in DIVA and LAGRANGE. Diversification rates were inferred by LASER and APE packages. Our results support two major clades within Carya, corresponding to the lineages of eastern Asia and eastern North America. The split between the two disjunct clades is estimated to be 21.58 (95% HPD 11.07-35.51) Ma. Genus-level DIVA and LAGRANGE analyses incorporating both extant and extinct genera of the Juglandaceae suggested that Carya originated in North America, and migrated to Eurasia during the early Tertiary via the North Atlantic land bridge. Fragmentation of the distribution caused by global cooling in the late Tertiary resulted in the current disjunction. The diversification rate of hickories in eastern North America appeared to be higher than that in eastern Asia, which is ascribed to greater ecological opportunities, key morphological innovations, and polyploidy.  相似文献   

4.
木兰科(Magnoliaceae)的起源、进化和地理分布   总被引:31,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   

5.
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   

6.
1. The distribution of Salix species among the continents. There are about 526 species of Salix in the world, most of which are distributed in the Northern Hemisphere with only a few species in the Southern Hemisphere. In Asia, there are about 375 species, making up 71.29 percent of the total in the world, including 328 endemics; in Europe, about 114 species, 21.67 percent with 73 endemics; in North America, about 91 species, 17.3 percent with 71 endemics; in Africa, about 8 species, 1.5 percent, with 6 endemics. Only one species occurs in South America. Asia, Europe and North America have 8 species in common (excluding 4 cultivated species). There are 34 common species between Asia and Europe, 14 both between Europe and North America and between Asia and North America, 2 between Asia and Africa. Acording to the Continental Drift Theory, the natural circumstances which promoted speciation and protected newly originated and old species were created by the orogenic movement of the Himalayas in the middle and late Tertiary. Besides, the air temperature was a little higher in Asia than in Europe and North America (except its west part) and the dominant glaciers were mountainous in Asia during the glacial epoch in the Quaternary Period. Then willows of Europe moved southwards to Asia. During the interglacial period they moved in opposite direction. Such a to-and-fro willow migration between Asia and Europe and between and North America occurred so often that it resulted in the diversity of willow species in Asia. Those species of willows common among the continents belong to the Arctic flora. 2. The multistaminal willows are of the primitive group in Salix. Asia has 28 species of multistaminal willows, but Europe has only one which is also found in Asia. These 28 species are divided into two groups, “northern type” and “southern type”, according to morphology of the ovary. The boundary between the two forms in distribution is at 40°N. The multistaminal willows from south Asia, Africa and South America are very similar to each other and may have mutually communicated between these continents in the Middle or Late Cretaceous Period. The southern type willows in south Asia are similar to the North American multistaminal willows but a few species. The Asian southern type willows spreaded all over the continents of Europe, Asia and North America through the communication between them before the Quaternany Period. Nevertheless, it is possible that the willows growing in North America immigranted through the middle America from South America. The Asian northern type multistaminal willows may have originated during the ice period. The multistaminal willows are more closed to populars in features of sexual organs. They are more primitive than the willows with 1-3 stamens and the most primitive ones in the genus. 3. The center of origin and development of willows Based on the above discussion it is reasonable to say that the region between 20°-40°N in East Asia is the center of the origin and differentiation of multistaminal willows. It covers Southern and Southwestern China and northern Indo-China Pennisula.  相似文献   

7.
林有润 《植物研究》2002,22(3):341-365
棕榈科原省藤亚科因其子房壁及外果皮被倒生、螺旋状排列的鳞片所覆盖,而区别于其他亚科,因而独立分出成一新科--省藤科。作者讨论了棕榈科的祖先种可能在石炭纪时,自原始裸子植物开以顿目在分化、衍生出苏铁目祖先种的进化干上,于白垩纪时分化出的一个分支。在棕榈科的祖先种出现不久后,在其进化的分支上,于白垩纪后期又分化出一旁支,成为棕榈科的姊妹科--省藤科的祖先种。从两祖先种分别再分化、衍生出现今分布地球上该二科的属与种。两科、尤其前者是被子植物、尤其是单子叶植物中最原始的类群之一。作者还提出棕榈科象牙椰亚科与贝叶棕亚科是该科最原始或较原始的两类群;槟榔亚科和腊材榈亚科是较进化的两类群;而水椰亚科祖先种可能源于象牙椰亚科的祖先种,但又演化为该科最进化与特化的类群。省藤科省藤亚科略比鳞果榈亚科原始。作者讨论了两科为泛热带分布的科,指出两科的"现代分布区"在南北两半球热带地区,少数种还延伸分布到两半球暖亚热带、甚至达中亚热带地区,分布区边缘最北达日本中部、中国长江流域及黄河下游的南部,美国加利佛尼亚州与佛罗里达州和地中海北部;最南达智利中部和新西兰南部;而"现代分布中心"在热带与暖亚热带的亚洲,中、南美洲,大洋洲及非洲的东、南、西部;但分布区的"密集中心"则在热带亚洲、热带中及南美洲、南太平洋群岛及非洲东南部。作者还介绍了近50年我国南方引种驯化成功的两科植物近400种(见*图谱),其中少数为耐寒的种类,有的种已引种到长江流域或更北的地区。引种的大部分种都有其重要的经济用途,包括:1. 食用,如淀粉和树液可制"西米"或制糖,酿酒、醋或作饮料;果或种子榨油,供食用或工业用;某些种的嫩芽作蔬菜,甚至种子代咖啡饮用;2. 药用,有消炎、止血、活血、驱虫、抗癌等用;3. 建筑、工艺与日用品,包括不少种的树干供建普通房子、桥梁、小船;少数种可提制工业用蜡;许多种的纤维制高级缆绳和编织品;还制工艺品与日用品等;4. 代表热带景观的园林工程、绿化及美化环境的观赏树和人行道树及建造园林景观生态类型的树种等。  相似文献   

8.
Cypripedium kentuckiense is a recently described rare orchid found in Arkansas (predominantly) and in eight other states. Much debate has focused on whether this taxon should be recognized as a distinct species or considered to be an extreme manifestation of the variability present in the widespread taxon Cypripedium parviflorum var. pubescens. In this study, 12 isozyme loci were analyzed for 14 populations of C. parviflorum var. pubescens and eight populations of C. kentuckiense. These data were used to examine the genetic similarity of these taxa, assess whether isozyme data support the continued recognition of C. kentuckiense as a distinct species, and assess whether a newly discovered disjunct Virginia population of C. kentuckiense is genetically isolated from other C. kentuckiense populations. The isozyme data revealed that the two taxa are very closely related with a high interspecific genetic identity. However, C. kentuckiense populations contain a subset of the variation present in C. parviflorum var. pubescens, and they have expected levels of heterozygosity that are one-quarter that of C. parviflorum var. pubescens populations. Cypripedium kentuckiense also possesses one widespread unique allele and a unique multilocus genotype. These data suggest that C. kentuckiense should be recognized as a distinct species, possibly of recent origin from C. parviflorum. Lastly, the isozyme data support the hypothesis that gene flow between the Virginia population and other populations of C. kentuckiense has been restricted.  相似文献   

9.
安息香科的系统位置及地理分布   总被引:4,自引:0,他引:4  
安息香科为柿目的一成员,包括11个属,为一自然的分类群.它与山茶科很接近,并可能是从它的祖先类群演化而来的.本文分析其形态特征的演化趋势,认为子房上位,花冠裂片覆瓦状排列,雄蕊为花冠裂片两倍,花序圆锥花序为原始性状,而子房下位.花冠裂片镊合状排列,雄蕊与花冠裂片的同数,花序少花或单花为进化性状.安息香属为本科最大的属,形态变异多样化,既具有最原始性状,为本科原始类群代表,同时又有较多进化性状.其他各属可能是以它作为基干演化而来.从分析各属的分布区类型,本科有7属分布于热带地区,但仅有3属真正分布于热带,其余4属分布于亚热带或其边缘地区.因此,安息香科基本上是一个热带科,但不典型,它可能是从古热带山区的亚热带地区演化而来的.根据全科的属和种的统计,有11属,150余种,间断分布于欧亚和美洲两大陆块上,亚洲有10属,57种,主要分布于东亚,在这一地区,以我国秦岭和长江以南至南岭以北及华西南种类最丰富,包括有最原始类群和系统演化各阶段类群;热带南美洲有2属83种,这一带种类虽丰富,但仅2属及缺乏原始类群.因此,我们称东亚为安息香科的分布和分化中心,而热带南美洲为第二分布中心.根据化石记载结合本科现代分布格局,我们  相似文献   

10.
丽江杓兰大围山变种(Cypripedium lichiangense vat.daweishanense)被提升为种的等级:大围山杓兰(Cypripedium daweishanense)。此种的特征是:中萼片浅黄绿色,上面疏被栗色斑点;花瓣较短,近等长于或略长于唇瓣。而丽江杓兰(Cypripedium lichiangense)的中萼片为紫肝色;花瓣要长得多,大约为唇瓣长的2倍。它们均属于三棱组(Cypripedium sect.Trigonopedium)。该组共含11种,均为中国特有种。文中提供了一个该组的分种检索表。  相似文献   

11.
The present paper aims to discuss the geog raphical distribution of the Juglandaceae on the basis of unity of the phylogeny and the process of dispersal in the plants. The paper is divided into the following three parts: 1. The systematic positions and the distribution patterns of nine living genera in the family Juglandaceae (namely, Engelhardia, Oreomunnea, Alfaroa, Pterocarya, Cyclocarya, Juglans, Carya, Annamocarya and Platycarya) are briefly discussed. The evolutional relationships between the different genera of the Juglandaceae are elucidated. The fossil distribution and the geological date of the plant groups are reviewed. Through the analysis for the geographical distribution of the Juglandaceous genera, the distribution patterns may be divided as follows: A. The tropical distribution pattern a. The genera of tropical Asia distribution: Engelhardia, Annamocarya. b. The genera of tropical Central America distribution: Oreomunnea, Alfaroa. B. The temperate distribution pattern c. The genus of disjunct distribution between Western Asia and Eastern Asia: Pterocarya. d. The genus of disjunct distribution between Eurasia and America: Juglans. e. The genus of disjunct distribution between Eastern Asia and North America: Carya. f. The genera whose distribution is confined to Eastern Asia: Cyclocarya, Platycarya. 2. The distribution of species According to Takhtajan’s view point of phytochoria, the number of species in every region are counted. It has shown clearily that the Eastern Asian Region and the Cotinental South-east Asian Region are most abundant in number of genera and species. Of the 71 living species, 53 are regional endemic elements, namely 74.6% of the total species. The author is of the opinion that most endemic species in Eurasia are of old endemic nature and in America of new endimic nature. There are now 7 genera and 28 species in China, whose south-western and central parts are most abundant in species, with Province Yunnan being richest in genera and species. 3. Discussions of the distribution patterns of the Juglandaceae A. The centre of floristic region B. The centre of floristic regions is determined by the following two principles: a. A large number of species concentrate in a district, namely the centre of the majority; b. Species of a district can reflect the main stages of the systematic evolution of the Juglandaceae, namely the centre of diversity. It has shown clearly that the southern part of Eastern Asian region and the northern part of Continental South-east Asian Region (i.c. Southern China and Northern Indo-China) are the main distribution centre of the Juglandaceae, while the southern part of Sonora Region and Caribbean Region (i.c. South-western U.S.A., Mexico and Central America) are the secondary distribution centre. As far as fossil records goes, it has shown that in Tertiary period the Juglandaceae were widely distributed in northern Eurasia and North America, growing not only in Europe and the Caucasus but also as far as in Greenland and Alaska. It may be considered that the Juglandaceae might be originated from Laurasia. According to the analysis of distribution pattern for living primitive genus, for example, Engelhardia, South-western China and Northern Indo-China may be the birthplace of the most primitive Juglandaceous plants. It also can be seen that the primitive genera and the primitive sections of every genus in the Juglandaceae have mostly distributed in the tropics or subtropics. At the same time, according to the analysis of morphological characters, such as naked buds in the primitive taxa of this family, it is considered that this character has relationship with the living conditions of their ancestors. All the evidence seems to show that the Juglandaceae are of forest origin in the tropical mountains having seasonal drying period. B. The time of the origin The geological times of fossil records are analyzed. It is concluded that the origin of the Juglandaceae dates back at least as early as the Cretaceous period. C. The routes of despersal After the emergence of the Juglandaceous plant on earth, it had first developed and dispersed in Southern China and Indo-China. Under conditions of the stable temperature and humidity in North Hemisphere during the period of its origin and development, the Juglandaceous plants had rapidly developed and distributed in Eurasia and dispersed to North America by two routes: Europe-Greenland-North America route and Asia-Bering Land-bridge-North America route. From Central America it later reached South America. D. The formaation of the modern distribution pattern and reasons for this formation. According to the fossil records, the formation of two disjunct areas was not due to the origin of synchronous development, nor to the parallel evolution in the two continents of Eurasia and America, nor can it be interpreted as due to result of transmissive function. The modern distribution pattern has developed as a result of the tectonic movement and of the climatic change after the Tertiary period. Because of the continental drift, the Eurasian Continent was separated from the North American Continent, it had formed a disjunction between Eurasia and North America. Especially, under the glaciation during the Late Tertiary and Quaternary Periods, the continents in Eurasia and North America were covered by ice sheet with the exception of “plant refuges”, most plants in the area were destroyed, but the southern part of Eastern Asia remained practically intact and most of the plants including the Juglandaceae were preserved from destruction by ice and thence became a main centre of survival in the North Hemisphere, likewise, there is another centre of survival in the same latitude in North America and Central America. E. Finally, the probable evolutionary relationships of the genera of the Juglanda-ceae is presented by the dendrogram in the text.  相似文献   

12.
粉条儿菜属(AletrisL.)隶属于肺筋草科,全世界有23种1变种,东亚有18种1变种,北美东南部有5种,为典型的东亚-北美间断分布的属.本文在种(变种)的水平上,研究了粉条儿菜属的地理分布及其分布中心和多样化中心,并对其起源和分化以及现代洲际间断分布格局的成因进行了分析.结果表明,(1)中国共分布有粉条儿菜属植物15种1变种,而广义的横断山地区集中分布有13种1变种,是东亚粉条儿菜属植物分布最为集中的地区,而且包含该属植物各个进化阶段的代表.因此,广义的横断山地区是粉条儿菜属在东亚的分布中心和多样化中心.(2)根据粉条儿菜属及其近缘属的分布格局推测,该属可能在不晚于第三纪早期,起源于古北大陆.东亚和北美的粉条儿菜属植物形态区别明显,应该是隔离分化的结果.(3)该属植物可能曾经广布于北半球,后来地质、气候以及冰川等因素的变化,导致该属在一些地区灭绝,而仅存于东亚和北美东南部.(4)尽管横断山及其周边地区是东亚粉条儿菜属的多样化中心,但该地区很可能并不是粉条儿菜属最早的分化中心,因横断山地区周边的一些特有种可能是在晚近的时期形成的新特有种;另外,东亚粉条儿菜属一些原始的种类主要分布于我国中东部到日本一带.所以,中国中东部到日本一带可能是粉条儿菜属早期的分化中心.  相似文献   

13.
杓兰属植物的开花和结实动态   总被引:2,自引:0,他引:2  
郑桂灵  李鹏  台永东  安德军  寇勇  罗毅波 《生态学报》2010,30(12):3182-3187
作为被子植物中最进化的类群,兰科植物的开花和结实动态对制定其保护策略具有重要意义。利用20032007年的数据,对分布于四川黄龙寺自然保护区的5种杓兰的种群开花和结实动态进行了分析。结果表明所研究的所有杓兰种类均是自交亲和物种,但在自然条件下都必须依赖传粉媒介才能成功结实。尽管不同种类的杓兰植物具有不同的开花时间,但统计分析表明杓兰属植物的开花早晚与其结实率之间相关性并不显著,这可能因为不同的杓兰具有不同的传粉系统而导致的。而杓兰属植物的花期长短与结实率之间却呈显著的负相关,这可能是与杓兰属植物具有典型的欺骗性传粉系统相关的。另外,除绿花杓兰外,其他4种杓兰2003年的结实率明显高于20042007年间的结实率。而2003年一个突出的事件即是发生了SARS导致游客人数显著减少,暗示了人为活动对杓兰属植物成功结实具有比较大的影响。  相似文献   

14.
A molecular analysis was performed on 56 taxa in the orchid genus Cypripedium using nrDNA ITS and five chloroplast regions (trnH-psbA, atpI-atpH, trnS-trnfM, trnL-F spacer, and the trnL intron). The genus Cypripedium was confirmed as monophyletic. Our data provided strong support for monophyletic grouping of eight infrageneric sections (Subtropica, Obtusipetala, Trigonopedia, Sinopedilum, Bifolia, Flabelinervia, Arietinum, and Cypripedium) defined in earlier taxonomic treatments, and paraphyletic grouping of two sections (Irapeana and Retinervi). Within the genus Cypripedium, the first divergent lineage consisted of two Mesomaerican species, and subsequently the Cypripedium debile lineage from eastern Asia was split. Our study did not support the notion that two Asian species (Cypripedium subtropicum and Cypripedium singchii) were closely related to either Mesoamerican Cypripedium irapeanum or North American Cypripedium californicum, as indicated by previous interpretations based on morphological evidences. In addition, one pair of vicariant species, Cypripedium plectrochilum (eastern Asia) and Cypripedium arietinum (North America), unique to section Arietinum, was confirmed. Furthermore, within the monophyletic section Cypripedium two previously recognized subsections, Cypripedium and Macrantha, were shown to be paraphyletic. Our results suggested that this section split into two groups based on distribution (North America vs. Eurasia) instead of such previously used, morphological traits as flower color, and the shape of the lips (labellum) and lateral petals.  相似文献   

15.
Cypripedium calceolus was found in 1980 in Rebun Island off the north coast of Hokkaido, Japan, but the origin of this plant has been a controversial issue. In this study, we have made a comparative study by chloroplast DNA sequencing analysis among C. calceolus which occurs in Rebun Island and populations of C. calceolus from western Europe, China and far eastern Russia (Nakhodka), and also as references, C. macranthos in Japan and other Cypripedium species in North America. A Cypripedium cf. "calceolus", found recently in eastern Hokkaido, was also included in this analysis. The C. calceolus samples analyzed were categorized into three groups, i.e., those from Western Europe, from China and far eastern Russia, and from Rebun Island. The C. calceolus in Rebun Island was clearly different from the others in terms of DNA sequence and morphological features. The C. cf. calceolus from eastern Hokkaido and one sample from Nadhodka, Russia, were also classified into the same group as those from Rebun Island, although some differences in their morphological features were observed. It is concluded that the C. calceolus found in Rebun Island is not identical with those growing in Europe and China. In addition, it was found that it may be possible to classify C. macranthos into two groups, namely groups which include or do not include var. rebunense. An unidentified Cypripedium species found in Rebun Island falls into the same group as var. rebunense.  相似文献   

16.
夏蜡梅属起源的探讨   总被引:10,自引:0,他引:10  
本文对Nicely提出夏蜡梅属(Catycanthus L.)起源于北美洲美国东部后西向迁移到加利福尼亚和东亚的假设提出异议。无论从染色体资料还是形态性状的比较来看,夏蜡梅属可能以较原始的夏蜡梅(C.chinensis Cheng et S. Y.Chang)起源于东亚(中国)。  相似文献   

17.
三江并流区域野生杓兰属植物资源初报   总被引:3,自引:0,他引:3  
对三江并流区域的野生杓兰属植物的种质资源特点及分布规律作了描述,并提出了该区域野生杓兰属资源开发利用的建议.  相似文献   

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In this paper the classification of the genus Bergenia Moench is provided, its geographic distribution analysed, and the phylogeny also traced. Based on an analysis of morphological characters such as leaves, ocreas, branches of inflorescences, Pedicels, hypanthium, sepals, and glandular indumentum, thi genus is divided into 3 sections: 1. Sect. Scopulosae J. T. Pan, sect. nov., 2. Sect. Bergnia, 3. Sect. Ciliatae (A. Boriss.) J. T. Pan, stat. nov. The Sect. Scopulosae J. T. Pan may be considered as the primitive one, while Sect. Ciliatae (A. Boriss.) J. T. Pan may be regarded as the advanced one, with Sect. Bergenia in between. So far, the genus Bergenia Moench comprises 9 species in the total. Southeast Asia and North Asia (south and east Siberia, USSR) each have only 1 species, West Asia (Afghanistan) has 2, Central Asia (Kirghizia-Tajikistan-Uzbekstan area, USSR) 3, South Asia 4 (Nepal has 4, India, Pakistan and Kashmir area each has 3, Bhutan and Sikkim each has 2), East Asia 6. In East Asia, Mongolia and Korea each have only 1 species, but China has 6 (including endemic species 2 and new species 1). Sichuan Province and Xizang Autonomous Region each have 3, Yunnan Province 2, Shaanxi Province (Qinling Mountains) and Uygur Autonomous Region of Xinjiang each have only 1. Thus the distribution centre of this genus should be in the region covering Sichuan, Yunnan and Xizang. Moreover, it is noteworthy that Bergenia scopulosa T. P. Wang in Sect. Scopulosae seems to have retained primitive characters, for example, non-ciliate leaves and ocreas, glabrous pedicels, hypanthium and sepals, and this primitive species is found in Qinling Mountains and Sichuan. According to the distribution of the primitive species, the author suggests that the centre of origin of this genus be in the region covering Qinling Mountains and Sichuan.  相似文献   

20.
Trichoderma brevicompactum, a new species, was isolated from soil or tree bark in North, Central and South America, including the Caribbean Islands, and southwestern and southeastern Asia. Morphological and physiological characters, the internal transcribed spacer regions of the rDNA cluster (ITS1-5.8SrDNA-ITS2) and partial sequences of translation elongation factor 1-alpha (tef1) are described. Trichoderma brevicompactum is characterized by a pachybasium-type morphology, morphologically resembling other small-spored species referable to Trichoderma section Pachybasium but with essentially subglobose conidia. It is most closely related phylogenetically to Hypocrea lutea, from which it differs in morphological and physiological characters.  相似文献   

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