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The classical and numerical taxonomy, palynology and the geographical dis- tribution of the Genus Schizopepon are dealt with in the present paper.  Having comme- nted on various opinions regarding the systematic position of the genus, the present au- thors consider that C. Jeffrey’s treatment of Schizopepon as a new and monogeneric tri- be, Schizopeponeae, should be supported.      The gross morphological characters in the genus are assessed from the taxonomic point of view.  Some characters, such as stamens with an elongated connective or not, different insertions of ovules and various forms of ovaries and fruits, may be used for distinguishing subgenera.      The pollen grains of all the species were observed under light microscope (LM) and scanning electron microscope (SEM).  The results show that a strong differentiation has taken place in the pollen of the genus, and in consequence it may be regarded as an important basis for dividing subgenera and species. Especially it should be pointed out that degrees of development of colpi and positions of ora are positively correlated with the external characters used for distinguishing subgenera.      According to the morphological and palynological characters, the genus Schizopepon may be divided into three subgenera and eight species: 1. Subgenus Schizopepon: 5 spe- cies, S. bryoniaefolius Maxim., S. monoicus A. M. Lu et Z. Y. Zhang, S. dioicus Cogn., S. longipes Gagnep. and S. macranthus Hand.-Mazz.; 2. Subgenus Rhynchocarpos A. M. Lu et Z. Y. Zhang: 1 species, S. bomiensis A. M. Lu et Z. Y. Zhang; 3. Subgenus Neoschi- zopepon A. M. Lu et Z. Y. Zhang: 2 species, S. bicirrhosus (C. B. Clarke) C. Jeffrey and S. xizangensis A. M. Lu et Z. Y. Zhang.      The 8 OTU’s including all the species of this genus and 31 characters, of which 16 are morphological characters and 15 palynological characters, were used in the numerical taxonomic treatment.  After standardization of characters, the correlation and distance matrices were computed.  The correlation matrices are made to test the various clustering methods.  At last, the UPGMA clustering method was selected and its result is shown in the form of phenogram.  The result of numerical analysis is similar to that of the classical classification.      Schizopepon Maxim. is a genus of East Asia-Himalayan distribution. China has all 8 species and 2 varieties, of which 6 species are endemic. Based on the statistics of spedies number, the distribution centre of the genus is considered to be in the Hengduan Mountains (Yangtze-Mekong-Salwin water divides) and the adjacent areas of the southwest China.  相似文献   

3.
 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   

4.
From standpoint of floristic division,  Sichuan is located in the middle part of Eastern Asiatic Region (Takhtajan 1978) or is the area where Sino-Himalayan Forest Subkingdom and Sino-Japan Forest Subkingdom meet (wu 1979).  Here exist many so- called Arcto-Tertiary elements and newly originated species or races.  In order to bring the light the origin and differentiation of Eastern Asiatic elements,  cytological investi- gation on plants of this region are very significant.  The materials of the following 5 species were collected on Mt.  Emei in Sichuan Province.  Voucher specimens are kept in CDBI.       1.  Toricellia angulata  Oliver var. intermedia (Harms) Hu       PMC meiotic examination revealed n = 12 at diakinesis (Pl. I fig. 9)       Toricellia,  consisting of 2 spp.,  is endemic to Eastern Asiatic Region.  Based on our result along with the report of Toricellia tiliifolia (Wall.) DC. (2n=24) by Kuro- sawa (1977),  we argue that the basic chromosome number of Toricellia is 12.  Many authors,  such as Airy-Shaw (1973),  Dahlgren (1975,  1977),  Takhtajan (1969,  1980), Thorne (1983),  have adopted Hu’s (1934) treatment erecting it as a monotypic family Toricelliaceae.  Its systematic position,  whether closer to Cornaceae than to Araliaceae or vice versa,  has been in dispute.  Cytologically it seems closer to Araliaceae,  as shown anatomically (Lodriguez 1971),  because the basic chromosome number of Cornaceae s. 1. is x=11,  9,  8 (Kurosawa 1977),  whereas that of Araliaceae is 12 (Raven 1975).       2.  Cardiocrinum giganteum  (Wall.) Makino       Somatic chromosome number,  2n=24 was determined from root-tip cells (Ph. I. fig. 8).       Cardiocrinum (Endl.) Lindl.,  consisting of 3 spp.,  is endemic to Eastern Asiatic Region.  C. giganteum (Wall.) Makino is distributed from Himalayan region to S. W. China.  The present report is in accord with the number reported by Kurosawa (1966) who got the material from Darjeeling of India.  However the karyotype of the present plant is slightly different from that given by Kurosawa.  In the present material,  the satellites of the 1st. pair of chromosomes and the short arms of llst.  pair of chromoso- mes are visibly longer than those of Kurosawa’s drawing (fig. 1,  2) The plants from Yunnan,  Sichuan and Hubei Provinces,  named as C. giganteum var. yunnanense (Leit- chtlin ex Elwes) Stearn,  differ slightly from those of Himalayan region also in outer morphological characters.  The taxon needs both cytological and taxonomical further studies.       3.  Disporum cantoniense  (Lour.) Merr.       PMC meiotic examination revealed n=8 at diakinesis (Pl. I. fig. 6)       This species is widely distributed from Himalayan region through Indo-China to our Taiwan Province and Indonesia. Three cytotypes (2n=14,  16,  30) were reported for the taxon including its variety,  var. parviflorum (Wall) Hara,  by various authors (Ha- segawa 1932,  Mehra and Pathamia 1960,  Kurosawa 1966,  1971 Mehra and Sachdeva 1976a).  Some authors consider D. pullum Salisb. and D. calcaratum D. Don as synonyms of D. cantoniense. So D. cantoniense may be a species aggregate with different extreme races.  Sen (1973a,  b.) reports that the somatic chromosome numbers of D. pullum and D. calcaratum from Eastern Himalayan region are 14,  16,  28,  30,  32.  He also discovered that chromosome alterations in species of Disporum involve not only the num- ber but the structure as well.  He found that in species of Liliaceae where the reproduc- tion is mainly vegetative,  polysomaty often occurs.  In China we have not only D. can- toniense and D. calcaratum but also D. brachystomon Wang et Tang which is similar to D. cantoniense var. parviflorum (Wall.) Hara.  These taxa need further critical studies.      4.  Paris fargesii Franch.      PMC meiotic examination revealed n=5+2B (Voucher no. 112) or n=5 (Voucher no. 62) at MI and AI (Pl. I. fig. 1. 4. 5.).  This is the first report for the species.  A bridge and a fragment were also observed at AI.      Paris polyphylla Smith is extraordinarily polymorphic species.  Hara (1969) re- gards all chinese extreme forms,  such as P. fargesii Franch.,  P. violacea Lévl.,  P. pube- scens (Hand. -Mzt.) Wang et Tang,  etc. as infraspecific taxa of P. polyphylla.  Need- less to say,  the various races of P. polyphylla Smith in China need further critical stu- dies and are good material for further study to understand the speciation.      5.  Reineckia carnea(Andr.) Kunth       Reineckia is a monotypic genus endemic to Eastern Asiatic Region.  In the present material somatic chromosome number in root-tip cells is determined as 2n=38 (Pl. I. fig. 7).  According to the terminology defined by Levan et al.,  the karyotype formula is 2n=28 m+10 sm.  The length of chromosomes varies from 14.28 μ to 5.5 μ. The idiogram given here (fig. 3) is nearly the same as that presented by Hsu et Li (1984). The same number has been previously reported by several authors,  Noguchi (1936),  Satô (1942), Therman (1956).  The karyotype is relatively symmetrical (2B,  accorling to the classi-fication of stebbins 1971) in accord with the opinion of Therman (1956).  相似文献   

5.
正定价:498.00元(包括邮费)内容简介《中国统计年鉴—2013》系统收录了全国和各省、自治区、直辖市2012年经济、社会各方面的统计数据,以及多个重要历史年份和近年全国主要统计数据,是一部全面反映中华人民共和国经济和社会发展情况的资料性年刊。二、本年鉴正文内容分为25个篇章,即:1.综合;2.国民经济核算;3.人口;4.就业人员和工资;5.固定资产投资;6.对外经济贸易;7.资源和环境;8.能源;9.财政;10.价格指数;11.人民生活;12.城市概况;13.农业;14.工业;15.建筑业;16.运输  相似文献   

6.
本文报道了轮藻科2新种、1新变种、5个中国新记录:嫩江丽藻Nitella  nenjiangensis sp.  nov.,轮苞轮藻  Chara  vertillibracteata  sp.   nov.,  球状轮藻北京变种  Chara  globularis  Thuiller var.  beijingensis  var.  nov.,  腋生丽藻  Nitella axillaris  Braun,  卷曲丽藻N. crispa Imah.,柔细 丽藻N.  gracillima Allan,  拟扇形丽藻不完全变种N.  pseudoflabellata var. imperialis,阿鲁轮藻 Chara arrudensis Mendes.  相似文献   

7.
Baolia Kung et G. L. Chu was established on the basis of B. bracteata Kung et G. L. Chu described in 1978 from Diebu County on the border between Gansu and Sichuan provin- ces.  It is placed in the tribe Chenopodieae in 《Flora Reipulicae Popularis   Sincae》, but considering its flowers with a bract and 2 bracteoles it is betwter transferred to the tribe Polv- cenmeae. So far the tribe Polycnemeae contains 4 genera in total, i.e. Nitrophila S. Wats. with 4 species, distributed in Southwestern US, Mexico and Argentina, Hemichroa R.  Br. with 3 species all in Australia, Polycnemum Dumort. with 4 species in Europe,   Mediterranean, Middle Asia to Siberia, Baolia Kung et G. L. Chu with 1 species, occurring in central China with a very limited area.  相似文献   

8.
木兰科分类系统的初步研究   总被引:10,自引:0,他引:10  
A new system of classification of Magnoliaceae proposed.  This paper deals mainly with taxonomy and phytogeography of the family Magnoliaceae on the basis of external morphology, wood anatomy and palynology.  Different  authors have had different ideas about the delimitation of genera of this family, their controversy being carried on through more than one hundred years (Table I).  Since I have been engaged in the work of the Flora Reipublicae Popularis Sinicae, I have accumulated a considerable amount of information and material and have investigated the living plants at their natural localities, which enable me to find out the evolutionary tendencies and primitive morphological characters of various genera of the family.  According to the evolutionary tendencies of the characters and the geographical distribution of this family I propose a new system by dividing it into two subfamilies, Magnolioideae and Liriodendroideae Law (1979), two tribes, Magnolieae and Michelieae Law, four subtribes, Manglietiinae Law, Magnoliinae, Elmerrilliinae Law and Micheliinae, and fifteen genera (Fig. 1 ), a system which is different from those by J. D. Dandy (1964-1974) and the other authors.      The recent distribution and possible survival centre of Magnoliaceae. The members of Magnoliaceae are distributed chiefly in temperate and tropical zones of the Northern Hemisphere, ——Southeast Asia and southeast North America, but a few genera and species also occur in the Malay Archipelago and Brazil of the Southern Hemisphere. Forty species of 4 genera occur in America, among which one genus (Dugendiodendron) is endemic to the continent, while about 200 species of 14 genera occur in Southeast Asia, of which 12 genera are endemic.  In China there are about 110 species of 11 genera which mostly occur in Guangxi, Guangdong and Yunnan; 58 species and more than 9 genera occur in the mountainous districts of Yunnan.   Moreover,  one  genus (Manglietiastrum Law, 1979) and 19 species are endemic to this region.  The family in discussion is much limited to or interruptedly distributed in the mountainous regions of Guangxi, Guangdong and Yunnan.  The regions are found to have a great abundance of species, and the members of the relatively primitive taxa are also much more there than in the other regions of the world.      The major genera, Manglietia, Magnolia and Michelia, possess 160 out of a total of 240 species in the whole family.  Talauma has 40 species, while the other eleven genera each contain only 2 to 7 species, even with one monotypic genus.   These three major genera are sufficient for indicating the evolutionary tendency and geographical distribution of Magnoliaceae.  It is worthwhile discussing their morphological  characters  and distributional patterns as follows:      The members of Manglietia are all evergreen trees, with flowers terminal, anthers dehiscing introrsely, filaments very short and flat, ovules 4 or more per carpel.  This is considered as the most primitive genus in subtribe Manglietiinae.  Eighteen out of a total  of 35 species of the genus are distributed in the western, southwest to southeast Yunnan. Very primitive species, such as Manglietia hookeri, M. insignis  and M. mega- phylla, M. grandis, also occur in this region. They are distributed from Yunnan eastwards to Zhejiang and Fujian through central China, south China, with only one species (Manglietia microtricha) of the genus westwards to Xizang.  There are several species distributing southwards from northeast India to the Malay Archipelago (Fig. 7).      The members of Magnolia are evergreen and deciduous trees or shrubs, with flowers terminal, anthers dehiscing introrsely or laterally, ovules 2 per carpel, stipule adnate to the petiole.  The genus Magnolia is the most primitive in the subtribe Magnoliinae and is the largest genus of the family Magnoliaceae. Its deciduous species are distributed from Yunnan north-eastwards to Korea and Japan (Kurile N. 46’) through Central China, North China and westwards to Burma, the eastern Himalayas  and northeast India.  The evergreen species are distributed from northeast  Yunnan  (China)  to  the Malay Archipelago.  In China there are 23 species, of which 15 seem to be very primi- tive, e.g. Magnolia henryi, M. delavayi, M. officinalis and M. rostrata, which occur in Guangxi, Guangdong and Yunnan.      The members of Michelia are evergreen trees or shrubs, with flowers axillary, an- thers dehiscing laterally or sublaterally, gynoecium stipitate, carpels numerous or few. Michelia is considered to be the most primitive in the subtribe Micheliinae, and is to the second largest genus of the family.  About 23 out of a total of 50 species of this genus are very primitive, e.g. Michelia sphaerantha, M. lacei, M. champaca,  and  M. flavidiflora, which occur in Guangdong, Guangxi and Yunnan (the distributional center of the family under discussion)  and extend eastwards to Taiwan  of  China, southern Japan through central China, southwards to the Malay Archipelago through Indo-China. westwards to Xizang of China, and south-westwards to India and Sri Lanka (Fig. 7).      The members of Magnoliaceae are concentrated in Guangxi, Guangdong and Yunnan and radiate from there.  The farther away from the centre, the less members we are able to find, but the more advanced they are in morphology.  In this old geographical centre there are more primitive species, more  endemics  and  more monotypic genera. Thus it is reasonable to assume that the region of Guangxi, Guangdong and Yunnan, China, is not only the centre of recent distribution, but also the chief survival centreof Magnoliaceae in the world.  相似文献   

9.
 A comparison of morphology, karyotype and the chemical compounds among “Jinxiong”, Ligasticum chuanxiong Hort. and L. chuanxiong cv. Fuxiong shows that “Jin- xiong”, like L. chuanxiong cv. Fuxiong, is a triploid and its karyotype is similar to that of L. chuanxiong with the formula K(2n)=33=24m+6sm+3st(SAT).   Thin-layer chromato- graphy of essential oils extracted from stem tubers confirms that the three taxa are extremely alike in chemical compounds. Using the features of leaves and the forms of stem tubers, they can be easily distinguished.  A new triploid cultivar of L. chuanxiong Hort. i.e.L. chuan-xiong cv. Jinxiong   is described for “Jinxiong” in the present paper.  相似文献   

10.
The  vegetative  characters of  Ligusticum  chuanxiong  Hort.  cv.  Fuxiong are described in comparison with L. chuanxiong Hort. and L. sinense Oliv. The chromosome numbers and karyotypes of the three taxa were studied in root tip cells by Feulgen’s squash method. Their karyotypes are determined as follows: L. chuanxiong, K(2n)=22=16 m+ 4sm+2st (sat); L. chuanxiong cv. Fuxiong, K(2n)=33=24 m+6sm+3st (sat); L. sinen- se, K(2n)=22=12 m+6sm+2sm (sat)+2st (sat).      The karyotypic similarities are found between L. chuanxiong and its cultivariety, butthe former is a diploid while the latter probably is a homologous triploid.  相似文献   

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