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1.
Xizang (Tibet) is rich in Leguminosae flora, comprising 41 genera and 254 species
so far known, exclusive of the commonly cultivated taxa (including 11 genera and 16
species). There are 4 endemic genera (with 8 species), 10 temperate genera (with 175
species) and 19 tropical genera (with 46 species) as well as the representatives of those
genera whose distribution centers are in East Asia-North America, Mediterranean
and Central Asia.
1. There are altogether 4 endemic genera of Leguminosae in this region. Accord-
ing to their morphological characters, systematic position and geographical distribution,
it would appear that Salweenia and Piptanthus are Tertiary paleo-endemics, while
Straceya and Cochlianths are neo-endemics. Salweenia and Piptanthus may be some
of more primitive members in the subfamily Papilionasae and their allies are largely
distributed in the southern Hemisphere. The other two genera might have been derived
from the northern temperate genus Hedysarum and the East Asian-North American
genus Apios respectively, because of their morphological resemblance. They probably
came into existanc during the uplifting of the Himalayas.
2. An analysis of temperate genera
There are twelve temperate genera of Leguminosae in the region, of which the
more important elements in composition of flora, is Astragalus, Oxytropis and Cara-
gana.
Astragalus is a cosmopolitan genus comprising 2000 species, with its center
distribution in Central Asia. 250 species, are from China so far known, in alpine zone of
Southwest and Northwest, with 70 species extending farther to the Himalayas and
Xizang Plateau.
Among them, there are 7 species (10%) common to Central Asia, 12 species (15.7%)
to Southwest China and 40 species (60%) are endemic, it indicates that the differentia-
tion of the species of the genus in the region is very active, especially in the subgenus
Pogonophace with beards in stigma. 27 species amounting to 78.5% of the total species of
the subgenus, are distributed in this region. The species in the region mainly occur in
alpine zone between altitude of 3500—300 m. above sea-level. They have developed into
a member of representative of arid and cold alpine regions.
The endemic species of Astragalus in Xizang might be formed by specialization of
the alien and native elements. It will be proved by a series of horizontal and vertical vicarism of endemic species. For example, Astragalus bomiensis and A. englerianus are
horizontal and vertical vicarism species, the former being distributed in southeast part
of Xizang and the latter in Yunnan; also A. arnoldii and A. chomutovii, the former
being an endemic on Xizang Plateau and latter in Central Asia.
The genus Oxytropis comprises 300 species which are mainly distributed in the
north temperate zone. About 100 species are from China so far known, with 40 species
extending to Himalayas and Xizang Plateau. The distribution, formation and differ-
entiation of the genus in this region are resembled to Astragalus. These two genera are
usually growing together, composing the main accompanying elements of alpine mea-
dow and steppe.
Caragana is an endemic genus in Eurasian temperate zone and one of constructive
elements of alpine bush-wood. About 100 species are from China, with 16 species in Xi-
zang. According to the elements of composition, 4 species are common to Inner Mon-
golia and Kausu, 4 species to Southwest of China, the others are endemic. This not only
indicates that the species of Caragana in Xizang is closely related to those species of
above mentioned regions, but the differentiation of the genus in the region is obviously
effected by the uplifting of Himalayas, thus leading to the formations of endemic species
reaching up to 50%.
3. An Analysis of Tropical Genera
There are 19 tropical genera in the region. They concentrate in southeast of Xizang
and southern flank of the Himalayas. All of them but Indigofera and Desmodium are
represented by a few species, especially the endemic species. Thus, it can be seen that
they are less differentiated than the temperate genera.
However, the genus Desmodium which extends from tropical southeast and northeast
Asia to Mexio is more active in differentiation than the other genera. According to Oha-
Shi,s system about the genus in 1973, the species of Desmodium distributed in Sino-Hima-
laya region mostly belong to the subgenus Dollinera and subgenus Podocarpium. The
subgenus Dollinera concentrates in both Sino-Himalaya region and Indo-China with 14
species, of which 7 species are endemic in Sino-Himalaya. They are closely related to
species of Indo-China, southern Yunnan and Assam and shows tha tthey have close con-
nections in origin and that the former might be derived from the latter.
Another subgenus extending from subtropical to temperate zone is Podocarpium.
Five out of the total eight species belonging to the subgenus are distributed in Sino-
Himalaya and three of them are endemic.
An investigation on interspecific evolutionary relationship and geographic distribu-
tion of the subgenus shows that the primary center of differentiation of Podocarpium
is in the Sino-Himalaya region.
Finally, our survey shows that owing to the uplifting of the Himalayas which has
brought about complicated geographic and climatic situations, the favorable conditions
have been provided not only for the formation of the species but also for the genus in cer-tain degree. 相似文献
2.
木兰科分类系统的初步研究 总被引：10，自引：0，他引：10
刘玉壶 《中国科学院研究生院学报》1984,22(2):89-109
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
3.
1) The Compositae in Tibet so far known comprise 508 species and 88 genera,
which nearly amounts to one fourth of the total number of genera and one third of the
total number of species of Compositae in all China, if the number of 2290 species and 220
genera have respectively been counted in all China. In Tibet there are all tribes of Com-
positae known in China, and surprisingly, the large tribes in Tibetan Compositae are
also large ones in all China and the small tribes in Tibet are also small ones in all China.
Generally speaking, the large genera in Tibet are also large ones in all China and the
small genera in Tibet are likewise small ones in all China. In this sense it is reasonable to
say that the Compositae flora of Tibet is an epitome of the Compositae flora of all China.
In the Compositae flora of Tibet, there are only 5 large genera each containing 30
species or more. They are Aster, Artemisia, Senecio, Saussurea and Cremanthodium. And
5 genera each containing 10—29 species. They are Erigeron, Anaphalis, Leontopodium,
Ajania, Ligularia and Taraxacum. In addition, there are 77 small genera, namely 87%
of the total of Compositae genera in Tibet, each comprising 1—9 species, such as Aja-niopsis, Cavea and Vernonia, etc.
2) The constituents of Compositae flora in Tibet is very closely related to those of
Sichuan-Yunnan provinces with 59 genera and 250 species in common. Such a situation
is evidently brought about by the geographycal proximity in which the Hengtuang Shan
Range links southeastern and eastern Tibet with northern and northwestern Sichuan-
Ynnnan. With India the Tibetan Compositae have 59 genera and 132 species in common,
also showing close floristic relationships between the two regions. Apparently the floris-
tic exchange of Compositae between Tibet and India is realized by way of the mountain
range of the Himalayas. The mountain range of the Himalayas, including the parallel
ranges, plays a important role as a bridge hereby some members of the Compositae of
western or northern Central Asia and of the northern Africa or of western Asia have
migrated eastwards or southeastwards as far as the southern part of Fibet and northern
part of India, or hereby some Compositae plants of eastern and southeastern Asia or
Asia Media have migrated northwestwards as the northern part of Central Asia.
Some of the species and genera in common to both Tibet and Sinjiang indicate that
this weak floristical relationship between these regions is principally realized through two
migration routes: one migration route is by way of the Himalayas including the parallel
ranges to Pamir Plataeu and Tien Shan, or vice versa. The other migration route is by
way of northern Sinjiang to Mongolia, eastern Inner Mongolia, southwards to Gansu,
Qinghai (or western Sichuan), eastern Tibet up to the Himalayas, or vice versa.
However, Tibet is not entirely situated at a migration crossroad of the floral ele-
ments. An ample amount of the data shows that Compositae flora have a particular
capability of development in Tibet. of the total number of species of Tibetan Com-
positae, 102 species and 1 genus (Ajaniopsis Shih) are endemic. Besides, 8 genera are re-
gional endemics with their range extending to its neighbourhood. The higher percentage
of endemics at specific level than at generic in Tibetan Compositae may be a result of
active speciation in response to the new enviromental conditions created by the uplifting
of the Himalayas. The flora in Tibetan Plateau as a whole appears to be of a younger
age.
3) The uprising of the Himalayas and of the Tibetan Plateau accompanied by the
ultraviolet ray radiation, the microthermal climate and the high wind pressure has, no
doubt, played a profound influence upon the speciation of the native elements of Tibetan
Compositae. The recent speciation is the main trend in the development of the Com-positae flora native in Tibet in the wake of upheaval of the plateau. 相似文献
4.
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
5.
鄂西神农架地区的植被和植物区系 总被引：1，自引：0，他引：1
Shennungia is generally known as “The highest mountain in Central China”. It is
situated at latitude 31°342'N., longitude 110°35'E. in western Hupeh.
The area explored is deeply cut in all sides by five V-shaped valleys, giving the
landscape a steep topography. Its summit is about 3105 meters above the sea level, and
the relative altitude is from 1000-2000 meters.
The climate of the region is warm temperate. The differences of humidity-warmth
condition between the eastern and the western flanks are quite marked.
In western Hupeh and the adjacent area of Szechuan the rugged topography still
preserves some tracts of natural forests at higher elevations. Our vegetational survey
is confined to localities above 1500 meters. The collection of plant samples of the flora
is extended to the whole mountain from the foothill to the peak. The present article
deals with only a part of the results of our survey.
1. The vertical vegetation belts of Mt. Shennungia and relationships with other
regions: The vegetation belts on the eastern and the western flanks of the mountain
are shown in diagram 2 and 3. The comparison of the vertical vegetation zones of the
Mt. Shennungia with those of the Yülungshan in N. W. Yunnan and the eastern
Himalaya to the west and with those of Hwangshan and Central Japan to the east
is shown in table 4, It shows that the plant communities of the Mt. Shennungia are of
temperate nature, and they are more closely related to those of Hwangshan in S.
Anhwei and of Central Japan than to the eastern Himalaya.
2. Floristic composition: The generic ranges of flowering plant are relatively
distinct and stable. Various distributional patterns of genera are analysized.
1) Statistics of the genera in various distributional patterns: The total number
of genera of flowering plants in this region are 762, belonging to the following four
categories. A) tropical genera 239 (31.3%), B) temperate genera 416 (54.7%), C)
endemic genera 47 (6%), and D) comsmopolitan genera 61 (8%).
2) Endemic genera: An examination of the composition of the flora in western
Hupeh reveals that 47 endemic Chinese genera occur in this mountain of which 24 are
monotypic genera, 20 oligotypic and 2 multitypic as shown in Table 4. The arborescent
genera are nearly all deciduous. They are of temperate nature.
3) Temperate genera: There are 416 genera in wastern Hupeh. They are
subdivides into the following three groups according to their distributional patterns:
A) The north temperate genera: There are 159 genera belonging to 62 families in
western Hupeh. B) Eastern Asian genera: There are 117 genera belonging to 69
families in western Hupeh. Among them 22 are common to the western Szechuan,
adjacent regions of Yunnan and the Eastern Himalaya. The remaining 95 genera are
commom to both eastern China and Japan. C) The Eastern Asian-eastern North-
American genera: Of the total 762 genera known in western Hupeh, 64 are disjunc-
tively distributed in both eastern Asia and eastern North-America.
4) The tropical genera: Of the 762 genera of the flowering plant of western
Hupeh, 239 (31%) are of tropical nature.
Finally, our survey shows: 1. Many of the primitive temperate genera and ende-
mic relicts concentrate in western Hupeh and the adjacent region of Szechuan indica-
ting that it might be one of refuges of tertiary flora. Moreover, it might also be one
of the most important regions of differentiation, development and distribution of tem-
perature flora. 2. The vegetation of this region is not only of temperate nature, but
also of a transitional nature. 3. According to an analysis of the flora and a compari-
son of the vertical distribution of the vegetation of Yülungshan and Eastern Himalaya
to the west with Hwangshan and Central Japan to the east, the floristic affinity of
western Hupeh is more closely related to eastern China and Central Japan rather than
to the Eastern Himalaya, and phytogeographically this region is intermediate between
the Sino-Himalayan and the Sino-Japanese patterns. However, the problem of phyto-
geography of western Hupeh and the adjacent region of Szechuan is a complicated
one requiring further study.
相似文献
6.
中国种子植物特有属的数量分析 总被引：3，自引：0，他引：3
王荷生 《中国科学院研究生院学报》1985,23(4):241-258
Chinese flora with many endemic elements is highly important in the world’s
flora. According to recent statistics there are about 196 genera of spermatophytes, be-
ing 6.5% of total Chinese genera. These endemic genera comprising 377 species belong
to 68 families, among which the Gesneriaceae (28 genera), Umbelliferae (13), Compo-
sitae (13), Orchidaceae (12) and Labiatae (10) are predominant. The tropical type
containing 24 families and 80 genera is dominant. After it follows the temperate type
with 23 families and 50 genera. There are also 4 families endemic to China, i.e. Gin-
kgoaceae, Bretschneideraceae, Eucommiaceae and Davidiaceae. It shows that genera
endemic to China are obviously related to the tropical and temperate flora in essence.
The endemic monotypic genera (139) and endemic obligotypic genera (48) combin-
ed make up more than 95% of the total number of genera endemic to China. Phylo-
genetically more than half of them are ancient or primitive. The life forms of all ende-
mic genera are also diverse. Herbs, especially perennial herbs, prevail with the propor-
tion of about 62%, and trees and shrubs are the next, with 33%, and the rest are lianas.
Based upon the calculated number of genera endemic to China in each province and
the similarity coefficents between any two provinces, some conclusions may be drawn
as follows:
Yunnan and Sichuan Provinces combined are the distribution centre of genera en-
demic to China and may be their original or differentiation area, because numerous
endemic genera, including various groups, exist in these two provinces. The second is
Guizhou where there are 62 endemic genera. Others form a declining order, south
China, central China and east China. But towards the north China endemic genera de-
crease gradually, and the Qinling Range is an important distributional limit.
The largest simitarity coefficient, over 50%, appears between Shaanxi and Gansu
probably because of the Qinling Range linking these two provinces. But between any
other two provinces it is less than 30% and it is generaly larger between two south pro-
vinces than between two north provinces.
These characteristics mentioned above are correlated with topography and climate,
and they may be resulted from the diversification in geography and climatic influence
for a long time. 相似文献
7.
张芝玉 《中国科学院研究生院学报》1982,20(4):402-409
1. The present paper describes the observations of chromosome numbers and
karyomorphology of 2 species of 2 endemic genera and I endemic species of Chinese
Ranunculaceae: Asteropyrum peltatum (Franch.) Drumm et Hutch. 2n=16, x=8;
Kingdonia unifolia Balf. f. et W. W. Sm. 2n=18, x=9 and Calathodes oxycarpa Spra-
gue 2n=16, x=8. The chromosome counts of three ranunculaceous genera are repor-
ted for the first time.
2. The morphylogical, palynological and cytological date in relation to the syste-
matic postition of Asteropyrum, Kingdonia and Calathodes within the family Ranun-
culaceae are diseussed and resulted in following conclusions:
(1). On the basis of the basic number x=8 in Asteropyrum, it is further con-
firmed that this genus is distinct from the r elated genera such as Isopyrum, Dichocarp-
um and other allied taxa.
The comparison of Asteropyrum with Coptis shows that they are identical in short
chromosomes, with magnoflorina and benzylisaquinodine type of alkaloides, but dif-
ferent from coptis in the chromosome numbers (T-type), pantocolpate pollens, united
carpels and the dorsi-ventral type of petioles. In view of these fundamental morpho-
logical and cytological differences, Asterop yrum is better raised to the level of Tribe.
However Asteropyrum and Coptis may represent two divaricate evolutional lines of
Thalictroideae.
(2). The systematic position of the genus Kingdonia has been much disputed in
the past. We support the view of Sinnote (1914), namely, the trilacunar in leaf
traces “the ancient type”, appeared in the angiosperm line very early, while the uni-
lacunar of Kingdonia may be derived from the trilacunar. On the basis of the chromo-
some numbers and morphylogical observation, the present writer accept Tamura’s and
Wang’s treatment by keeping Kingdonia in Ranunculaceae instead of raising it to a
family rank as has been been done by Forster (1961). Kingdonia and Coptis are
similar in having short chromosome with x=9, but with one-seeded fruits; therefore it
is suggested that placed into Thalictroideae as an independent tribe, indicating its close
relationship with Coptideae.
(3). Comparing with its allies, Calathodes being with out petals, seems to be more
primitive than Trollius. But Calathodes differs from Trollius with R-type chromosomes in having T-type chromosome with x=8 and subterminal centromere. Those charac-
teristics show that it is very similar to the related genera of Thalictroideae. But as
Kurita already pointed out that most speci es of Ranunculus have usually large long
chromosomes but some species have compar ativelly short chromosomes, therefore we
regard T-type and R-type chromosomes appear independently in different subfamilies
of Ranunculaceae. According to Tamura, G alathodes seems to be closely related to
Megaleranthis, because of the resemblance in follicles. But due to lack of cytological
data of the latter genus, the relationship between the two genera still is not clear pen-
ding further studies. From the fact that the morphology and chromosomes of the
Calathodes differs from that of all other genera of the Helleboroideae, we consider
Calathodes may form an independent tribe of its own with a closer relationship withTrollieae. 相似文献
8.
This paper is a preliminary study on the Sabiaceae in aspects of its morphology,
taxonomy and geography. We propose that the Sabioideae and Meliosmoideae as two
new subfamilies of Sabiaceae according to the external morphology, flower structure
and geographical distribution of these two genera respectively.
This paper follows the taxonomic concepts of Luetha Chen on Sabia and C. F.
van Beusekom on Meliosma. We agree with them for their classification of these two
genera above the specific rank. As to the revision work of Sabia by van de Water
and C. F. van Beusekom’s work on Meliosma we disagree for their unduly broad
specific concepts. We rather treat the species of these two genera according to their
habitats in regions on a relatively narrower sense. The genus Sabia of China are
classified into 2 tribes, with 16 species, 5 subspecies and 2 varieties in which 4 sub-
species and l variety are as new combinations, the genus of Meliosma in China are
classified into 2 subgenera with 29 species, and 7 varieties of which 4 varieties are new
combinations.
After examining the affinity of the species of Sabia and Meliosma in China and
its neighboring nations such as Burma, Japan and Bhutan, we found that their migra-
tion initiated from China, as the primitive species of these two genera occured in
northeast and central part of Yunnan, sou theast of Sichuan, north of Guizhou and
west of Hubei, the region may probably be the main origin of these two genera.
As shown in tables 1 & 2, the localities where the species of these two genera den-
sely populate they are from Yunnan, Guangxi, and Guangdong coinciding with the
concepts of C. F. van Beusekom and van de Water about the distribution of exotic
species of these two genera, it may reasonable be pointed out that the center of distri-
bution of these two genera is Yunnan, Guangxi, Guangdong and nieghboring nations,
upper Burma and northern Vietnam. Futhermore, it may be seen that starting from
this center the number of species become less and less as they proceed far and far awaybut become more advance in evolution. 相似文献
9.
10.
A karyotypical analysis of Anemarrhena asphodeloides Bung. of the monotypic genus
Anemarrhena Bung. (Liliaceae) was carried out for the first time. The number of chromo-
somes in root-tip cell of the species was found to be 22, agreeing with that reported by Sato[12], although inconsistent in some other respects, such as position of centromeres, length of chromosomes, and nucleoli, etc. (Table 1 ). According to the terminology defined by Levan et al.［8］, the karyotype formula is therefore 2n=22=2sm (SAT)+2sm+18m.
Photomicrographs of the chromosome complements and idiogram of the karyotype are given
Fig. 1 and 2).
The karyotype of Anemarrhena asphodeloides shows explicitly to be asymmetrical, with three pairs of long chromosomes and eight pairs of short chromosomes. This specialized feature, when considered together with the rare occurrence of the basic chromosome number of 11 of the genus within the Tribe Asphodeleae of Liliaceae (see Table 1), suggests that the genus Anemarrhena is probably a rather specialized one, which has scarcely any intimate relationship with the other genera of the above tribe. The fact that this specialized karyotype is associated with certain trends of morphological specialization, such as flowers possessing three stamens only, gives support to the above suggestion. But, it is impossible to draw a more precise conclusion without a more thorough and comprehensive investigation of the species in question. 相似文献
11.
广义的安息香科(Styracaceae)有15个属，本文报道了其中13属93种植物的光学显微
镜与扫描电镜的花粉形态观察结果，根据这15个属的花粉形态特征可将它们归之为三个花粉
类型，即：安息香型，山矾型及非洲安息香型。在Wagenitz(1964)的安息香科系统中所包括
的11个成员，正好都是属安息香型花粉的那11个属，因此他的观点可以从花粉形态方面获得
有力的支持。将其他的四个属，即：山矾属(Symplocos)，非洲安息香属(Afrostyrax)，蒜味树属
(Hua)，尖药树属(Lissocarpa)从安息香科中分出的处理是合理的。狭义的安息香科有11个
属，其中大多数属之间，在花粉形态上较难区分，这是由于安息香属的花粉形态变异幅度可以
将其它几个属的都包括进去。因此我们认为，狭义的安息香科是一个很自然的分类群，安息香属以外的10个属可能都是通过安息香属在进化过程中衍生而得的产物。 相似文献
12.
本文作者对国产鼠李科枣族6属19种的花粉形态进行了光学显微镜和扫描电镜的观察，根据孔沟交界处四块加厚的程度和所形成的H形明显与否以及纹饰的不同作出了分属检索表。同时根据花粉形态特征讨论了有关属的分类学上的问题。 相似文献
13.
席以珍 《中国科学院研究生院学报》1986,24(4):247-252
红豆杉科(Taxaceae)，花粉近球形，有时稍扁或稍长。直径为20．8-45．8μm。具远极 薄壁区，或不典型的乳头状突起。外壁两层，内外层厚度相等，有时层次不明显。在光学显微 镜下，外壁表面粗糙，或具微弱的颗粒状纹饰。在穗花杉(Amentotaxus argotaenia)这个种里，有些花粉粒具残存气囊。在扫描电镜下，外壁表面具粗瘤和细瘤两种纹饰类型。透射电镜本科各属代表种观察表明，本科花粉外壁内层具片状结构，外层由单层瘤状纹饰分子构成，有 些种细瘤连接形成覆盖层。根据花粉形态资料，可将本科植物分为2个族： 白豆杉族(仅包括白豆杉一个属)和红豆杉族(包括红豆杉属和榧树属)。 鉴于穗花杉属花粉的特殊性，建议独立上升为穗花杉科Amentotaxaceae。 相似文献
14.
小檗科Berberidaceae花粉形态研究 总被引：1，自引：0，他引：1
本文对小檗科我国主产区——四川所采标本，以及我国新疆和朝鲜、苏联的
少量标本共11属33种进行了较系统、较深入的花粉形态研究，试图在此基础上 对小檗科属间的亲缘关系及其归属问题提供一些参考资料。 相似文献
15.
本文对国产鼠李科鼠李族5属25种的花粉形态进行了光学显微镜和扫描电镜的观察，并观察了
乌苏里鼠李的外壁超微结构。根据花粉大小、孔沟交界处四块加厚的程度和所形成的H形明显与否以及纹饰的不同作出了分类检索表，同时根据花粉形态特征认为把鼠李属的裸芽亚属和鳞芽亚属分立成为两个独立的属是比较适宜的。 相似文献
16.
紫草科微孔草属及其近缘属花粉形态的研究 总被引：1，自引：0，他引：1
本文用光学显微镜和扫描电镜观察了微孔草属(Microula Benth.)6组16种及其相关的3属6
种植物的花粉，并对微孔草属2种和齿缘草属(Eritrichium Schrad.)2种花粉做了花粉壁超微结构的
研究。微孔草属及其相关的3属花粉为哑铃形，花粉体积很小，最大的为12.18×7.13μm,最小的只
有6.36×3.36μm，具相间排列的三孔沟和三假沟。但他们在赤道部位的缢缩程度、萌发孔特征、表
面纹饰及超微结构有明显的不同。从花粉形态看，微孔草属较原始，且与锚刺果属(Actinocarya Benth.)有较密切关系；齿缘草属具双内孔或单内孔且为异极，为进化类型。 相似文献
17.
吉占和 《中国科学院研究生院学报》1982,20(4):439-444
The present paper is an attempt to make a taxonomic study of the little known
orchid genus Holcoglossum, as well as a comparison of the genus with its allies, such
as Vanda, Papilionanthe, Ascolabium, Ascocentrum, Aěrides, Neofinetia and Saccola-
bium.
Holcoglossum was established by Schlechter in 1919 (Orchideologiae Sino-Japoni-
cae Prodromus) as a monotypic genus, based upon Saccolabium quasipinifolium Hayata.
Five years later he published another true Holcoglossum as Aěrides flavescens, which
was referred by Tang et Wang to Saccolabium in 1951. Further investigation of this
genus was by Garay in 1972 who added two species, H. kimballiana and V. rupestris
(synonymy of Aěrides flavescens), but considered Neofinetia, a quite different taxon,
to be congeneric. It is shown that the demarcation of Holcoglossum remains cofused.
During the course of our study, the species of Holcoglossum and its allied genera are
carefully examined, we come to the conclusion that Ho lcoglossum is a distinct genus.
It is characterized by the short stem; fleshy terete or subterete, sulcate above leaves,
with their apex acute and non-lobed; thickening or keeled costa on the back of sepals,
3-lobed lip, with erect sidelobes, paralled to the column; slender and recurved spur;
footless column usually with prominent wings; 2 notched pollinia attached to linear
stipe which is tapered toward the base. In addition to Ascolabium, it differs from
Vanda, Papilionanthe, Ascocentrum, Aěrides, Neofinetia and Saccolabium by its terete
or subterete leaves on their ventral side with a furrow, from Papilionanthe by lacking
footless column, from Ascolabium by sepals and spur characters, from Ascocentrum by
slender and recurred spur, from Aěrides by the absence of a column-foot and the
appearance of spur, from Neofinetia by stipe tapered toward the base, from Saccolabi-um by both aspects of the vegetative organs and the flowers. 相似文献
18.
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
19.
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