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1.
CAS botanists have made novel progress on studies of origin and domestication of the Asian cultivated rice Oryza sativa. Their work was published in the June issue of Genetics.  相似文献   

2.
 四合木属Tetraena Maxim.   是内蒙古自治区西部和亚洲中部荒漠区东部的特有属,也是珍稀   濒危植物。前人曾对该属的系统地位做过一些研究,但观点不一。作者通过对该属的研究历史、雌蕊、   果实、花粉粒、染色体等的综合研究后,建议将该属从TaxTaЛЖЯН系统(1987)蒺藜科的霸王亚科中分   出,成立一个新亚科——四合木亚科。本文还编写了蒺藜科(狭义的)分亚科检索表。  四合木属的系统   地位是:芸香目蒺藜科四合木亚科四合木属。  相似文献   

3.
The present paper is a first instalment on the Chromosome counts by the authors of Chinese ferns, representing 13 species collected from the eastern coastal provinces of China.  Our findings agree pretty well with the previous ones by botanists mainly in Japan.  The voucher specimens for the present study are all preserved in the Depart- ment of Biology, the East China Normal University, Shanghai.      We wish to thank Professor R. C. Ching for his constant encouragement andguidance in the study of Chinese fern cytology.  相似文献   

4.
 The present paper is a result of taxonomic study of Chinese Styracaceae plants. It contains 9 genera, 48 species, of which 2 species, 2 varieties are described as new and 2 new combinations are made, 21 species or varieties previously known to botanists distinctly are here reduced to synonyms.  Besides  the  author  also  discuss about itsgeographical distribution in China and the main systematic characteristics of Styrax.  相似文献   

5.
The Swedish 18th-century naturalist Carolus (Carl) Linnaeus is habitually credited with laying the foundations of modern taxonomy through the invention of binominal nomenclature. However, another innovation of Linnaeus' has largely gone unnoticed. He seems to have been one of the first botanists to leave his herbarium unbound, keeping the sheets of dried plants separate and stacking them in a purpose built-cabinet. Understanding the significance of this seemingly mundane and simple invention opens a window onto the profound changes that natural history underwent in the 18th century.  相似文献   

6.
鳞毛蕨属的生物系统学研究   总被引:1,自引:0,他引:1  
At the outset the paper begins with a brief discussion of the geographical origin of the genus Dryopteris. With the cytological data so far available the author presumed that the No- rthern Hemisphere and possibly Eurasia is the geographical origin of the genus and that the Eastern Himalayas, China and Japan is the centre of speciation of the genus, and thence has spread to other continents along several routes. He is also of the opinion that the genus  tends to evolve the highest grade of polyploidy where it has existed longest. On the other hand, he pointed out that the production of polyploids may occur most frequently in response to pressures which a group meets in the course of its migration in space and time, with  the  majority  of diploids persisting as relics close to the original centre of diversification.       He then described the progress of the biosystematics of the European and North American Dryopteris, which has been undertaken through a close cooperation among botanists, cytologists and phytochemists of different nations. This team is also looking forward to a cooperation with the Chinese botanists in the study of East Asian species of Dryopteris, so that the relationships of Chinese species and those of other floras can be understood.       The term biosystematics had been invented to mean experimental studies of breeding sy- stems of the species concerned in order to ellucidate their evolutionary relationships.  It stems from the early researches of Professor Irene Manton whose classical book “Problems of Cytology and Evolution in the Pteridophyta” (1950) laid the foundation of Biosystematics. Manton was also the first to introduce the acetocarmine squash  method for staining  chromosomes  in  the spore-mother-cells at meiosis.       The lecture was illustrated with diagrams showing in detail the pairing behaviour of the chromosomes at the metaphase in meiosis and the formation of the polyploidies of different levels.       Besides cytological approach two other techniques have been also applied to the systematic studies of Dryopteris. The first is the comparison of sporoderms  using the scaning  electron microscope, revealing different ornamentations on the pericine. The second is the study of plant chemistry, in particular, that of the phloroglucinoles by thinlayer chromatography.       The remaining far greater part of the paper is devoted to analysing cytologically the Eu- ropean and North American species of Dryopteris in three groups, showing the lines of experi-mental work that has resulted in the understanding of their evolutional relationships.  相似文献   

7.
Endersby J 《Endeavour》2001,25(1):3-7
Joseph Hooker became one of the most influential botanists of his day. He is best remembered as a friend of Charles Darwin and an early advocate of natural selection. However, after returning to Britain from his first major voyage, Hooker spent years struggling to find a paid position that would allow him to pursue his studies of plant classification and distribution. As he worked to establish himself, he also helped transform the status of botany as a discipline. In all his efforts, Hooker relied on a network of unpaid, colonial collectors, whose often-forgotten contributions to Victorian natural history are vital to the understanding of the professionalization of the sciences in the 19th century.  相似文献   

8.
William Bateson was one of the pivotal figures in the early history of genetics, having championed the promise of Mendelism to unravel the secrets of heredity. Many refer to the "school" of genetics he directed at Cambridge between 1900 and 1910, but few note that Bateson's group consisted primarily of women. Bateson turned to botanists, zoologists, and physiologists associated with Newnham College, Cambridge, for critical assistance in advancing his research program at a time when Mendelism was not yet recognized as a legitimate field of study. Cambridge women carried out a series of breeding experiments in a number of plant and animal species between 1902 and 1910, the results of which provided crucial evidence that both supported and extended Mendel's laws of heredity. This essay shows how the situation of women in science in the early twentieth century was a factor--along with scientific, institutional, social, and political developments--in establishing the new discipline of genetics.  相似文献   

9.
 The “Iconographia Plantarum” written by Wu Chi-Tseng in the Qing Dynasty (A. D. 1848) is a classical monumental work in the literature of botany. 1714 species of plants widely-spread all over 19 provinces of our country, especeally in Jiangxi, Hunan and Yunnan Provinces, were described in this book. nan and Yunnan Provinces, were described try, especeally in Jiangxi, Hunan and Yun.      In order to make the plant names coincide with the original material as possible, the author had commented upon chinese herbal in considerable detail.  Most of the plants were illustrated after their habitual appearence in somewhat clear manner. As a means for identifying certain species of the plant, this work has been playing an important role in development of modern botanical science in China.      In modern taxonomical books a great deal of chinese name of plants are originated from this book, and they were available for reference to numerous researchers both at home and abroad. On account of inadequate observation, a lot of mistakes or misleadings occured in this book, and often been overlooked by the later botanists.  Some of the modern authors still adhere to the work “Iconographia Plantarum”and even quoting the erroneous statement from it, thus we have to correct.      This paper annotates and commentates the misleading items of 36 species of plant, and calls for the attention to the future readers.    相似文献   

10.
11.
After having examined all specimens of the genus Prenanthes L. of Compositae in the Herbarium of Institute of Botany, Academia Sinica, I find that the classic concept on the genus Prenanthes established by G. Bentham in 1873 has not been held exactly by some of Euro- pean, American, Japanese and Chinese botanists. For example, W. B. Hemsley, S. T. Dunn, A. Franchet, S. Kitamura and C. C. Chang placed plants from China which belong to other groups into the genus; I also find that the classic concept of the genus is not clear.  The present paper makes a revision not only on the classic concept of the genus, but also on its concept assumed by the above-mentionded botanists.      With the combination of numerous (25-35), white or yellow ligular florets, numerous ribs of achenes, Prenanthes alba L. (Nabalus albus (L.) Shih, comb. nov.) is distinctly different from Prenanthes purpurea L., which has the combination of purple, few (5-15) ligular flo- rests and few ribs of achenes.  Nabalus Cass., as a genus established early (1825) by H. Cassini, should be restored.  It is not reasonable to treat Nabalus as a subgenus (E. B. Babcock et al. 1947) or a section (S. Kitamura, 1956) or as a synonym (G. Bentham, 1983) of the genus Preanathes L.       The present author recognizes seven species in the new revised genus  Prenanthes L.  in China, 4 of which are described as new.  In the genus Nabalus Cass.  only one species, N. ochroleuca Maxim., is distributed in Northeast China.       As Lactuca melanantha Franch. (1895), Prenanthes henryi Dunn (1903), P. glandulosa Dunn (1903), Lactuca triflora Hemsl. (1888) (it was transferred to Prenanthes L. by C. C. Chang in 1934), Prenanthes formosana Kitam. (1934) and P. wilsoni Chang (1934) all have campanulate involucres, purple phyllaries, purple dorsi-ventrally compressed achenes, longitu- dinal rids 6-9 on each side of achene truncate and beakless at its apex and pilose tubes of co- rollae, they should be placed neither into the genus Prenanthes with obtusely tri-or pentagonous, subterete achenes and glabrous tubes of corollae, nor into the genus Lactuca with beak achenes. Besides the above-mentioned species misnamed by some of foreign and Chinese botanists, 6 other species also have the same structure in achenes and corollae.  Evidently, they fall into a new genus with the name Notoseris Shih.       The new genus Notoseris Shih of the tribe Lactuceae of Compositae seems to be more re- miniscent of Lactuca L. than of Prenanthes L. emend.       All the 12 species of the genus Notoseris Shih are endemic to China and distributed in the area of south of Yantze River. Of them 6 are new combinations and 6 are described as new.  相似文献   

12.
中国大节竹属的研究   总被引:1,自引:0,他引:1  
  相似文献   

13.
松杉类裸子植物的大孢子叶球理论评述   总被引:1,自引:0,他引:1  
系统评述了迄今为止在裸子植物球果类种鳞形态学本质方面存在过的各种观点及研究进展。将 这些观点归纳为7大类:(1)Delpino和Penzig等主张种鳞为叶性器官的叶性说;(2)Sachs和Eichler认为种鳞相当于叶舌的叶舌说;(3)Bessey认为种鳞不过是胚珠合点端增生的结果的独特结构说;(4)Kubart等提出生胚珠构造的假种皮学说;(5)Arber的半枝学说;(6)Dupler的珠被说认为红豆杉类胚珠的肉质化部分为珠被性质的构造;(7)由Schleiden和Braun提出并由Florin等发展的枝性说则以充分的证据论证了种鳞的枝性本质。关于球果类裸子植物种鳞的性质和来源,本文作者赞同Florin枝性本质的论述;但对该构造现存式样的组成和演化过程,笔者认为该构造是在个体发育中不甚分化的专营生殖的枝性复合构造,由早期裸子植物次级生殖枝及其相关构造经过系统发育变态、融合演化形成。  相似文献   

14.
eterachopsis was proposed by the senior author as an independent genus of the family Aspleniaceae in 1940 with 2 species.  Since then much study on its morpho- logy,  anatomy,  gametophyte and palynology has been carried out by Nayar,  Bir,  Chan- dra & Nayar and Chang et al.,  and they are of the opinion that the genus like Ceterach, is a comparatively primitive element in the family Aspleniaceae.  The queer zigzag pa- tern of cutting of lanceolate fronds appears extraordinary in the family Aspleniaceae, and also suggests its antiquity in evolution. So far only 3 species  (C.  dalhousiae,  C. paucivenosa and C. magnifica) are recognized,  the former from W. Himalayas,  also known from Africa,  while the latter two from W. S. China (Yunnan).  However,  in the past forty years the Chinese botanists have discovered 2 more species as new in N. W. Yunnan,  thus bringing the total known species of the genus up to 5.  The present paper is a brief summary on the genus Ceterachopsis,  which will be published in detail in the Flora Sinica vol. 4.       Pteridologists are also divided in their views regarding the generic status of Cete- rachopsis with 5 well-defined species in Yunnan and the East Himalayas.  We prefer to mintain it as a genus separate from Asplenium on account of its distinct morpholo- gical features.  It is to be hoped that more species may come to light in the mountainsin N. W. Yunnan through further exploration now under way.  相似文献   

15.
本文借助光学显微镜和扫描电镜,对国产交让术科10个种的气孔和花粉形态及金缕梅 科和黄杨科一些代表种的花粉形态进行了观察,并据大戟科已有资料,较系统地从形态学、解剖学、孢粉学、胚胎学以及化学成分等方面讨论交让木科的系统位置。  相似文献   

16.
 Parmelia is a genus of economical importance.   According  what  was  recorded, Meyen & Flotow were the first foreigners to study Chinese lichens in 1843.  Up to the present time 74 species, 24 varieties and 11 forms have been described from China.      The majority of specimens reported in this paper were collected by many Chinese botanists and collectors from 21 provinces from 1928--1962, while a few of them were collected by Licent from 1916 to 1917 and by Poliansky in 1957.      The system of classification adopted here is that held by A. Zahlbruckner in 1926. But in section Hypotrachyna, the two subsections-Myelochroa and Myeloleuca proposed by Asahina are adopted and Parmelia xanthocarpa which has not been properly placed before, is here referred to the subsection Myelochroa.      In the subgenus Hypogymnia the writer discovers that the length of spores of two species are longer than 10μ, especially  Parmelia macrospora reaches  17.5μ long.  So far as the writer knows, the upper limitation of the spore length  recognized  by  many lichenologists has been 10μ in this subgenus.  The spore measurement of this subgenus needs, therefore, to be revised in future.       In this paper 78 species, 14 varieties and 6 forms are presented.  Among them, 5 species, 5 varieties and 1 forms are considered as new and two new combinations have been made.  Out of all these, 31 species, 6 varieties and 2 forms are first recorded from China.  All the materials cited are deposited in the Mycological Herbarium of Instituteof Microbiology, Academia Sinica, Peking.  相似文献   

17.
 The purpose of the present paper is to discuss the systematic position of the genus Schnabelia originally proposed by H. Handel-Mazzatti in 1921, who considered it as be- longing to the family Verbenaceae, a point which he further emphasized in 1936.  How- ever, in his paper on the Chinese verbenaceous plants (1932), Prof. Pei Chien thought the genus should be removed from Verbenaceae into Labiatae and allied it with such genera as Ajuga and Teucrium on the ground that it also has deeply lobed ovary. Since then botanists on Chinese plants, such as Prof. Y. Z. Sun, F. C. How, etc. have always considered Schnabelia Hand.-Mazz. as a genus of Labiatae.      The present writer has recently studied the  genus,  comparing  its  morphology  of ovary, calyx lobes, pedicels, pollen grains, etc. with a number of verbenaceous genera, and comes to the conclusion that the genus should belong to Verbenaceae as H. Handel- Mazzatti first proposed and that it is closely allied to the genus Caryopteris, especially C. nepetaefolia (Benth.) Maxim.  Moreover, he considers that the deeply lobed ovary is not at all a good character even for generic separation, for several genera in Ver- benaceae, such as Caryopteris, Clerodendron, just like Teucrium and Ajuga of Labiatae, also have deeply lobed ovaries.      From the ample herbarium material, the present writer discovered for the first time that the genus Schnabelia has two types of flowers,  cleistogamous  and  chasmogamous. The original founder of the genus did not know this peculiar floral  character,  as  not mention of it was made in the generic diagnosis.  Chienodoxa Sun (1951) proves to be the present genus, which is based upon the cleistogamous type of flowers of an allied or perhaps the same species.    相似文献   

18.
Since the 19th century many botanists have studied the Chinese Cirsium and a great number of taxa or names has been reported,  of which many still need to be reviewed critically         This work is a preliminaxy result of study on Chinese species of Cirsium.  As many as 65 taxan or names in the literature are reduced to synonym in this paper.  The Cir- sium in China so far known comprises 49 species,  of which 9 are described as new,  1 is a new combination and 4 are new records in Chinese flora.   These new species are: C. subulariforme Shih,  S. muliense Shih,  C. fanjingshanense Shih,  C. periacanthaceum Shih, C. racemiforme Ling et Shih,  C. vernonioides Shih,  C. chrysolepis Shih,  C. tenuifolium Shih and the new combination is C. viridifolium (Hand. -Mazz.) Shih. The new records in China are C. serratuloides (L.) Hill.,  C. incanum (S. G. Gmel.) Fisch. ex MB.,  C. la- natum (Roxb. ex Willd.) Spreng and C. alatum (S. G. Gmel) Bobr.       The Chinese Cirsium is divided into 8 sections in the present paper,  of which 3 are new,  namely,  Sect.  Isolepis Shih,  Sect. Tricholepis Shilh and Sect. Hymenolepis Shih, and I is a new combination,  namely,  Sect. Spanioptilon (Cass.) Shih.      In addition,  a new species of the genus Alfredia,  A. aspera Slih,  is described.  相似文献   

19.
新种墨脱毛兰可能是足茎毛兰的“异常整齐花”型。  “异常整齐花”现象在兰科中时     有所见,在不同分类群中情况各异,至今尚未见系统的研究。本文认为辐射对称花被是兰科的     正常特征之一,主要见于原始的种类和少数进化的种类,也不同程度地存在于“异常整齐花”实     体中。具辐射对称花被的兰科植物大多数不是“异常整齐花”型,判断时要参酌其他特点,持慎     重态度。兰科“异常整齐花”有两种情况,一是异常型,亦即正常植株中仅偶见“异常整齐花”,     或同一个种可同时产生“异常整齐花”植株与正常植株,两者并存。另一种情况是正常型,亦即     只产生“异常整齐花”,而无正常的两侧对称花。后者意味着在进化过程中的一种飞跃,即形成     了新植物。对此最好作为独立的种处理,特别是在它的来源还不清楚的情况下更是如此。目     前所认为的一些所谓“异常整齐花”实体,大都是推测而已,其中有些或许在将来会被证明为正    常的、原始的植物。  相似文献   

20.
 The pollen morphology of 11 species and 1 variety in the genus Lespedeza and its allied genera (Campylotropis, Kummerowia) from NE China was examined under light and scanning electron microscopes.      1.  Lespedeza Michx. (plate 1:1-6; 2:1-6; 3:1-6; 4:1-2)      Pollen grains prolate, rarely subprolate or spheroidal, elliptic or rarely suborbicular in equa- torial view, 3-lobed-rounded in polar view, tricolporate, colpus margins smooth or jagged.  Polar axis 20.7-33.1μm long, equatorial axis 15.4-20.9 μm long.  Exine reticulate or foveolate, lu- mina verrucose or smooth under SEM.      2.  Campylotropis Bge. (plate 4:3-4)      One species in NE China, C. macrocarpa (Bge.) Rehd.  Pollen grains prolate, elliptic in equatorial view, 3-lobed-rounded in polar view, 3-colporate, colpus linear, 25.1μm long, 1.79μm broad, colpus margins jagged, with a series of verrucae equal in size along one side visible under SEM.  Polar axis 19.7μm long, equatorial axis 14.6μm long.  Exine reticulate, lumina nearly rounded, verrucose at periphery under SEM.       3.  Kummerowia Schindl. (plate 4:5-6)       Pollen grains spheroidal, oblate or prolate, elliptic in equatorial view, obtuse-triangular in polar view, tricolporate, colups linear, 25.1μm long, 2.01μm  broad,  colpus margins sinuate. Polar axis 24.7-27.9μm long, equatorial axis 19.7-26.6μm long.  Exine reticulate or subreti- culate, lumina nearly rounded, with verrocae visible under SEM.       According to the pollen morphology of Lespedeza and its allied genera, the division of Lespedeza (s. lat.) into Lespedeza (S. str.), Campylotropis and Kummarowia by Schindler (1912) is reasonable.  The subdivision of Lespedeza (s. str.) into Sect.  Macrolespedeza and Sect. Lespe- deza by many botanists, and the treatment of Lespedeze juncea  (L. f.) Pers. var. inschanica Maxim. as an independent species (i.e. Lespedeza inschanics (Maxim). Schindl.) are also suppor- ted by the pollen morphology shown in the present work.  相似文献   

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