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1.
The present paper deals with the pollen morphology of 10 species and 1 variety of Loxostemon in China. The pollen grains were all examined under light microscope.
The pollen grains of Loxostemon are subspheroidal, spheroidal or prolate, 18--33×11.8-28 μ in size, 3-colpate, colpi 15-21 μ long and 1-2 μ wide. The exine is 1.5-3 μ thick with two indistinct or distinct layers.
All the pollen grains are generally reticulate under light microscope. They are distinctly or obscurely and finely reticulate. L. axillus and L. repens are generally similar in gross morphology, but the pollen grains of these two species are different. The pollen grains of L. axillus are regularly polygonally reticulate, colpi are acute-ended and the exine is about 3 μ thick, whereas those of L.repens are irregularly polygonally reticulate, colpi are enlarged at both ends and the exine is about 2.8 μ thick. L. incanus and L. stenolobus appear to have similar gross morphology, but the pollen grains of the former have exines with two distinct layers and a densely and finely reticulate ornamentation and those of the latter have exines with two indistinct layers and a flexuosely reticulate ornamentation. 相似文献
2.
The present paper describes the pollen morphology of 30 species belonging to 7 genera of Plumbaginaceae from China. The pollen grains were all examined under light microscope, and those of some species under scanning and transmission electron microscope.
The pollen grains of the family are subspheroidal, prolate or oblate, (37.5-74.5)× (40.4-81.9)μ in size, 3-colpate, rarely 4-6-colpate, only pancolpate in Ceratostigma willmottianum. The exine 2-layered, 2.0-7.4μ thick, sexine thicker than nexine, verrucate, reticulate or coarsely reticulate.
On the basis of the morphology, two types of pollen grains are distinguished in the
family:
(1) The pollen grains are 3-(rarely 4-6 ) or pancolpate, the exine verrucate. They are found in the tribe Plumbagineae (inculuding the genera Ceratostigma, Plumbago and Plumbagella).
(2) The pollen grains are all 3-colpate, the exine reticulate or coarsely reticulate. They are found in the tribe Staticeae (including the genera Acantholimon, Ikonnikovia, Goniolimon and Limonium ). 相似文献
3.
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
4.
5.
We have described a new genus Taihangia, collected from, the south part of Taihang
Mountain in northern China. At the same time, comparative studies on Taihangia with its
related genera have been made in various fields including external morphology, anatomy
of carpels, chromosome and pollen morphology by light, scanning and transmission electron microscope. In addition, isoperoxidases of two varietier were analysed by means of polya-crylamide gel slab electrophoresis. The preliminary results are as follows:
Morphology: The genus Taihangia is perennial and has simple leaves, occasionally
with 1—2 very small reduced lobes on the upper part of petiole; flowers white, andromo-
noecious and androdioecious, terminal, single or rarely 2 on a leafless scape; calyx and cpicalyx with 5 segments; petals 5; stamens numerous; pistils numerous, with pubescent styles, spirally inserted on the receptacle in bisexual flowers, but with less number of abortive and glabrous pistils in male flowers.
In comparison with the related genera such as Dryas, Geum, Coluria and Waldsteinia,
the new genus has unisexual flowers and always herbaceous habit indicating its advanced
feature but the genus has a primitive style with thin and short hairs as compared with the genus Dryas which has long, pinnately haired styles, a character greatly facilitamg anemo-choric dissemination. The styles of Taihangia are slender and differ from those of the ge-nus Geum which are articulate, with a persistent hooked rostrum, thus adapting to epizo-ochoric dissemination to a higher degree.
The anatomy of carpels shows the baral position of ovules in the genus Taihangia like those in other related genera such as Dryas, Geum, Acomastylis, Coluria and Waldsteinia. This suggests that the new genus and its related ones are in a common evolutionary line as compared with the other tribes which have a pendulous ovule and represent a separate evolutionary line in Rosaceae. Dorsal and ventral bundles in carpels through sections are free at the base. Neither fusion, nor reduction of dorsals and vertrals. are observed. This shows that the genus Taihangia is rather primitive.
Somatic chromosome: All the living plants, collected from both Honan and Hopei
Provinces were examined. The results show that in these plants the chromosome number
is 2n= 14, and thus the basic number of chromosome is x=7. Such a diploid genus is first
found in both anemochoric and epizoochoric genera. Therefore, in this respect Taihangia is primitive as compared with herbaceous polyploid genus Geum and related ones.
Pollen: The stereostructure shown by scanning electron microscope reveals that the pollen grains of the genus Taihangia are ellipsoid and 3-colporate. There are two types of exine sculpture. One is rather shortly striate and it seems rugulate over the pollen surface; the other is long-striate. The genus Dryas differs in having only short and thick striae over the surface. The genus is similar to the genera Geum, Coluria and Waldsteinia in colpustype, but differs from them in that they all have long, parallel striae which are distributed along the meridional line.
In addition, under transmission electron microscope, the exine in the Taihangia and related genera Acomastylis, Geum, Coluria, Waldsteinia and Dryas has been shown to be typically differentiated into two distinct layers, nexine and sexine. The nexine, weakly statined, appears to consist of endoxine with no foot-layer, in which the columellae are fused, and which is thicker beneath the apertures. The sexine is 2-layered, consisting of columellae and tectum. Three patterns of tectum can be distinguished in the tribe Dryadeae: the first, in the genera Taihangia, Acomastylis, Geum, Coluria and Waldsteinia, is tectate-imperforate, with the sculpturing elements both acute and obtuse at the top and broad at the base; the second, in the genus Dryas, is semitectate, with the sculpturing elements shown in ultrathin sections rod-like and broader at the top than at the base or as broad at the top as at the base, and the third, tectate-perforate, with the sculpturing elements different in size. From the above results, the herbaceous groups and woody ones have palynologically evolved in two distinct directions, and the genus Taihangia is related to other herbaceous genera such as Acomastylis, Geum, Coluria and Waldsteinia, as shown in the electron microphotographs of ultrathin sections. The genus Taihangia, however, is different from related herbaceous genera in that the pollen of Taihangia is dimorphic, i.e. in addition to the above pattern of pollen another one of the exine in Taihangia is rugulate, with the sculpturing elements shown in the ultrathin sections being obtuse or emarginate and nearly as broad at the top as at the base.
The interesting results obtained from the comparative analysis of morphology, ana-
tomy of carpels, chromosome countings, microscopic and submicrosocopic structures of pollen may enable us to evaluate the systematic position of Taihangia and to throw a new light on evolution of the tribe Dryadeae. It is well known that the modes of dissemination of rosaceous fruits play an important role in the expansion and evolution of the family. The follicle is the most primitive and the plants with follicles, like the Spiraeoideae, are mostly woody and mesic, while the achene, drupe and pyrenarium are derived. In Rosoideae having a achene is a common feature. Particularly in the tribe Dryadeae, which is distinguished from the other related tribes by having orthotropous ovules, the methods of dissemination of fruits have developed in three distinct specialized directions: anemochory with long, plumose styles (e.g. Dryas), formicochory or dispersed by ants or other insects, with the deciduous styles (e.g. Waldsteinia and Collria),and epizoochory with the upper deciduous stigmatic part and the lower persistent hooked rostrum, an adhesive organ favouring epizoochory dissemination (e. g. Geum and related taxa). Taihangia is a genus endemic to mesophytic
forest area of northern China. Due to its narrow range and specific habit as well as pubescent styles, neither perfectly adapted to anemochory nor to epizoochory, the genus Taihangia might be a direct progeny of the ancestry of anemochory. Maintaining the diploidy and having an ntermediate sculptural type of pollen, the new genus might probably represent a linkage between anemochory and zoochory (including epizoochory and dispersed by ants).
Experimental evidence from isoperoxidases shows the stable zymograms of root and
roostoks. The anodal isozyme of T. rupestris var. rupestris may be divided into 6 bands:
A, B, C, D, E, F, and T. rupestris var. ciliata into 4 bands: A, B, C, G. The two varietiesof the species share 3 bands: A, B, C. However, D, E and F bands are characteristic of var. rupestris and G band is limited to var. ciliata. As far as the available materials are concerned, the analysis of isoperoxidases supports the subdivision of the species into two varieties. 相似文献
6.
半蒴苣苔属的研究(续) 总被引：1，自引：0，他引：1
李振宇 《中国科学院研究生院学报》1987,25(3):220-230
The genus Hemiboea is a curious genus of the tribe Didymocarpeae (Cyrtandroi-
deae), characterized by its peculiar pistil with one fertile carpel and its follicle-like capsule. This genus has not yet been thoroughly studied since its establishment by C. B. Clarke in 1888. In
the present paper, the taxonomic history is briefly reviewed; the external morphology, leaf his-
tology, pollen morphology and geographical distribution are discussed; a key to the 21 species
recognized by the author is provided; and the economic uses reported in various publications
are summarized.
I. Morphology
(1) Sclereids The foliar sclereids, occurring in this genus and defined by their forms,
fall into two types.
(A) Vermiform selereids This type of sclereids is noted in 15 species and may be clas-
sified into two groups according to their positions in leaf tissues. Those of the first group
are interspersed in the ground tissue around the vascular bundles of leaves and noted in 12
species, i.e.H. longisepala, H. cavaleriei, H. bicornuta, H. fangii, H. omeiensis, H. gracilis,
H. glandulosa, H. mollifolia, H. pingbianensis, H. parviflora, H. strigosa and H. gamosepala,
and those of the second group are dispersed in the mesophyll, occurring in H. subcapitata, H.
henryi and H. latisepala.
(B) Astrosclereids The sclereids of this type are discovered for the first time in Hemiboea,
dispersed in the mesophyll of a single species, i.e.H. lungzhouensis.
No foliar sclereids are found in the remaining 5 species, i.e.H. integra, H. flaccida, H.
longgangensis, H. subacaulis and H. follicularis.
The differences in forms and positions of the foliar sclereids and their absence or pre-
sence are of great help in understanding the relationship between the infrageneric taxa.
(2) Pollen grains The pollen grains of 19 species were examined with LM and SEM.
They are 3-colporate, subglobose or prolate, 20-38.8×22-28μm. The exine is 1.3-2μm
thick and the sculpture is foveolate (e.g.H. cavaleriei) to reticulate (e.g.H. omeiensis). In
Sect. Subcapitatae the pollen grains are subglobose or prolate, while those of Sect. Hemiboea are
prolate.
No pollen grains are observed in anthers of 13 speciemens of H. subacaulis var. subacaulis
and var. jiangxiensis.
(3) Seed-coat Under SEM the seed-coat exhibits considerable diversity in the genus, fur-
nishing useful characters for explaining the relationship between the two sections.
2. Geographical distribution The genus Hemiboea ranges from the eastern border of the
Xizang Plateau and Yunnan Plateau eastwards to Ryu Kyu Islands, and from the southern
slope of the Qinling Range southwards to northern Vietnam. The karst region of S. E. Yun-
nan and W. Guangxi is the centre of maximum variation of the genus and is probably its origin
centre, where the most primitive taxon exists, and where more species (13 species, i.e. 61.9 per
cent of the sum total) and more endemic species (8 species) are found than elsewhere.
3. Classification The genus consists of 21 species and 6 varieties which are classified into
2 sections. The Clarke's classification is accepted, but emended here as follows:
Sect. 1. Subcapitatae Clarke Sepals free or posterior ones connate. Muri of the seed-coat
laevigate or rugose; bottom of meshes flat, smooth or with few verrucae. Pollen grains subglo-
bose or prolate.
Sect. 2. Hemiboea Sepals connate. Muri of the seed-coat tuberculate or aliform-tuberculate;
bottom of meshes flat or concave, with dense verrucae. Pollen grains prolate.
Based on the analysis of external and internal morphological characters, the main evolu-
tionary trends in the genus are discussed and enumerated, and a hypothesis indicating the re-
lationships between the two sections is given. 相似文献
7.
8.
洪德元 《中国科学院研究生院学报》1980,18(1):50-52
While we were investigating the world Veroniceae we found the genus Wulfenia Jacq.
discontinuously distributing. W. carinthiaca and W. baldaccii are found in south-eastern Europe
and W. orientalis in Turkey and Lebanon, whereas W. amherstiana is a native of W. Hima-
laya. Such a pattern of distribution, discontinuous between the Mediterranean and W. Himala-
ya, as far as we know, is hardly frequent. After comparing carefully the specimens from these
two places and examining their pollen grains we got the impression that the difference between
the plants occuring near the Mediterranean and those in Himalaya is so big that they should
no longer be placed in the same genus. It would be necessary, therefore, to describe W. amhe-
rstiana as a new and separate genus (we name it Wulfeniopsis Hong). Its corolla is not 2-
lipped, but with four lobes (not five) lanceolate, acuminate and erect (not spreading). The
stigma is very small, not 2-lobed. Pollen grains are much smaller, with colpi more narrow and
lacking of membranes, and their exines are smooth (not reticulate). It’s chromosome numberis 2n = 16 (not 18). 相似文献
9.
张志耘 《中国科学院研究生院学报》1988,26(5):394-403
The morphological characters in the genus Orobanche were evaluated from the
taxonomic point of view. The author finds that the plants of this genus are relatively similar
to each other in respect to characters of vegetative organs, fruits and seeds. But the differences
in the floral structures can be served as a basis for delimitating infrageneric taxa. The seed
coat of 18 species and pollen grains of 6 species were also examined under scanning electron
microscope (SEM). They seem to have little significance for distinguishing species.
The result supports G. Beck’s (1930) division of the genus Orobanche into 4 sections, of
which 2 occur in China, based on the characters of the inflorescence, bracteoles and calyx.
The author considers that some characters, such as anther hairy or not, upper lip of corolla
entire or not, lower lip longer or shorter than the upper one, the state of corolla-tube inflec-
tion and the hair type of filaments and plants, are important in distinguishing Chinese species.
A key to the species of Orobanche in China is given.
This genus consists of about 100 species, and is mostly confined to Eurasia, with over 60
species found in Caucasus and Middle Asia of USSR, where may be the mordern distribu-
tional centre.
Orobanche L. in China is represented by 23 species, 3 varieties and l forma. As shown in
Table 1, most species (12 species) are found in Xinjiang, which clearly shows a close floristic
relationship between this region and Middle Asia of USSR. 6 species are endemic to China,
of which 4 are confined to the Hengduan Mountains (Yangtze-Mekong-Salwin divide).
The relationships between this genus and related ones of Orobanchaceae are also discussed.
The author holds the following opinions: the genus Phelypaea Desf. should be considered as a
member of Orobanche L. Sect. Gymnocaulis G. Beck, the monotypic genus, Necranthus A.
Gilli endemic to Turkey, is allied with Orobanche L. Sect. Orobanche, the monotypic genus,
Platypholis Maxim, endemic to Bonin Is. of Japan, is far from Orobanche L. in relation and
should be regarded as a separate genus.
The 11 OTU’s, including all the sections of Orobanche L. and 7 genera of Orobanchaceae,
and 15 morphological characters were used in the numerical taxonomic treatment to test the
above-mentioned suggestions. After standardization of characters, the correlation matrices were
computerized. The correlation matrices were made to test the various clustering methods. At
last the UPGMA clustering method was chosen and its result is shown in a phenogram. The
result of numerical analysis is basically in accordance with the suggestions. 相似文献
10.
马尾树科的形态及分类系统位置的讨论 总被引：1，自引：0，他引：1
张芝玉 《中国科学院研究生院学报》1981,19(2):168-178
The present paper is devoted to a study of the basic morphological and anatomical
characteristics of the endemic family Rhoipteleaceae from China. The fundamental
pattern of the morphological and anatomical characteristics of the Rhoipteleaceae is
similar to those of the Juglandaceae in wood anatomy, resinous peltate scales, apetaly,
bicarpellate pistils, one-seeded fruits and exalbuminous seeds. Whereas Rhoipteleaceae
has stipules; perfect flowers with superior 2-loculed ovaries, anatropous ovules and two
integuments; vessel elements of the secondary xylem with the scalariform perforation,
and 2–8 (18) pores on the oblique plate being observable; vascular rays heterocellular
and tricolporate pollen. The above characteristics–at least most of them, agree
pretty well with those depicted by Manning in his “Pre-Juglandaceae”. It is quite
possible that the Juglandaceae is derived from “Pre-Juglandaceae”by way of the
Rhoipteleaceae, as the morphological and anatomical features as indicated above tend to
show that the Rhoipteleaceae is more primitive than Juglandaceae.
The Rhoipteleaceae was previously considered as related to the Betulaceae or
Ulmaceae, a view, which the present study does not prove to be acceptable. Both Takh-
tajan (1969) and Cronquist (1968) pointed out that the Juglandales, Urticales, Myrica-
les, Fagales are all direct derivatives from the Hamamelidales. However, since the
Rhoipteleaceae is simillar to the Betulaceae in wood anatomy and pollen, it seems that
there too could have certain relationships between the Rhoipteleaceae and the Betula-ceae in the course of evolution. 相似文献
11.
按照花粉外壁表面纹饰的不同，可将春黄菊族中下列各属分为两大类群：(1)明显具刺：亚菊
属Ajania Poljak., 女蒿属Hippolytia Poljak., 百花蒿属Stilpnolepis Krasch.。 (2)具退化状小刺：紊蒿属
Elachanthemum Ling et Y.R.Ling，线叶菊属Filifolium Kitam., 画笔菊属Ajaniopsis Shih，喀什菊属
Kaschgaria Poljak．)，栉叶蒿属Neopallasia Poljak．，绢蒿属Seriphidium Poljak．。根据花粉形态特征，我们认为将紊蒿属和百花蒿属仍分为两个相互独立的属较为适宜。 相似文献
12.
13.
独叶草花粉形态的研究及其在分类上的意义 总被引：1，自引：0，他引：1
张玉龙 《中国科学院研究生院学报》1983,21(4):441-444
独叶草 (Kingdonia uniflora Balfour f．et W．W．Smith) 为我国特有植物，
由于它的开放的二叉分枝叶脉，引起了植物学家的很大兴趣和广泛注意，并从
各个方面对它进行了研究。关于它的花粉形态，除Forster(1961)曾有过简短
描述外，国内外都未研究过。本文对它的花粉形态进行了系统的研究，通过光学
显微镜、扫描电镜和透射电镜观察了它的外部形态和外壁结构。 并讨论了有关 分类问题。 相似文献
14.
在观察大量标本和野外考察的基础上，认为Nannoglottis souliei (Franch．)Ling et Y．L. Chen应作为N．gynura (C．Winkl．)Ling et Y．L. Chen的异名。 相似文献
15.
本文借助光学显微镜和扫描电镜，对豹子花属Nomocharis 6种植物和百合属Lilium 4
种植物的花粉形态与外部特征作了较系统的比较研究，其结果如下： 1．豹子花属植物花粉的
萌发孔均为单沟(远极)型，根据其外壁结构及表面纹饰的特点，可分为基柱网纹型和网纹
型，结合外部形态特征推断，可能存在由基柱网纹→网纹的进化趋势。 2．百合属植物花粉
的萌发孔多为单沟(远极)型，稀为2一3孔型，然而，其中外部形态极为相近的小百合集合群与
尖被百合在花粉形态上表现出较大的差异，这一事实为研究百合科花粉的演化提供了线索。豹
子花属与百合属花粉虽在表面纹饰上存在区别，但从外部形态上，该属的一些种类与百合属极 为相近，反映出二属之间存在着较为紧密的亲缘关系。 相似文献
16.
潘开玉 《中国科学院研究生院学报》1987,25(4):264-293
按本文处理，马铃苣苔属Oreocharis包括27种、5变种，其中有5个新种、4个新变
种。文中分析研究了该属的外部形态和地理分布; 在扫描电镜(SEM)下，对22个种的花粉
外壁和16个种的种皮进行了观察。结果认为花冠有三个类型，花药有两个类型，花粉和种皮
的外壁纹饰也可各分为三个类型。花冠的各种类型是稳定的，它们与花粉粒和种皮的特征明
显相关。其相关性是该属次级划分的主要依据。该属分为四个组。以O．bodinieri建立的
属，Dasydesmus Craib被并入Oreocharis。 相似文献
17.
本文对金缕梅科Hamamlidaceae蜡瓣花属Corylopsis 11种花粉进行光学显微镜和扫描电镜的观察研究。本属花粉除Corylopsis sinensis少量花粉具4沟外均为三沟类型。外壁均具网状纹饰，网眼形状大小略有差异，花粉粒大小虽有些变化，但其它特征均较一致，故在植物分类上本属是相当自然的一个类群。 相似文献
18.
本文就壳斗科三棱栎属Trigonobalanus Forman在我国的新分布——三棱栎T．doicha-
ngensis 的花粉作了光学显微镜、扫描电镜及透射电镜观察。从花粉的形状、萌发孔类型及外壁结构看，三棱栎与本科其余各属均不同，在壳斗科中确属一个独特类型。 相似文献
19.
梁元徽 《中国科学院研究生院学报》1988,26(4):265-281
本文报道在光学显微镜与扫描电镜下，对中国姜科Zingiberaceae中的2亚科(姜亚科、
闭鞘姜亚科)、3族、18属、89种、3变种植物花粉形态的观察结果。根据萌发孔的有无，将本
科的植物花粉分成两大类型，无萌发孔型和具萌发孔型。根据花粉粒形状、大小及萌发孔的类
型和外壁表面纹饰的不同，在两大类型中又区分为6亚型和2组。在无萌发孔类型中有：光
滑亚型、具刺亚型(内分短刺组和长刺组)、具条纹亚型和具脑皱状-负网状亚型，在具萌发孔类
型中有具沟-孔混合亚型及具散孔亚型。本文从花粉学的观点，对科内某些分类群的划分进行了讨论。 相似文献