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1.
安徽黄山木本植物区系中一些种的细胞学研究(Ⅰ)   总被引:1,自引:1,他引:0  
报道了黄山地区18种木本植物的染色体数,分属于15个科中的18个属,其中14种和2个属为首次报道,同时对Aphananthe,Fortunearia,Loropetalum,Holboellia,Platy-carya属的染色体数及其在分类上上的意义作了简单讨论。  相似文献   

2.
中国西部高山8种龙胆属植物的染色体数目   总被引:1,自引:1,他引:0  
本文报道了我国西部高山上的8种龙胆属植物的染色体数目。其中宽筒龙胆的染色体数目为2n=48,提钟龙胆的染色体数目为2n=26,小齿龙胆和四数龙胆的染色体数目为2n=24,南山龙胆的染色体数目为2n=18,上述5种植物的染色体数目为首次报道,其余蓝玉簪龙胆的染色体数目为2n=24,线叶龙胆的染色体数目为2n=48,钻叶龙胆的染色体数目为2n=18。  相似文献   

3.
石斛属的染色体数Ⅰ.10种   总被引:1,自引:0,他引:1  
本文报道10种国产石斛属(Dendrobium)植物的染色体研究结果。它们的染色体均属小型染色体,长度为1—3.47μm.染色体数皆为2n=38。其中有6种和国内外报道的结果相同,有4种为首次报道。  相似文献   

4.
刘建全 《植物研究》1999,19(4):392-396
报道了青海南部三种紫苑属植物的核型,染色体间期和前期 色体分别为复杂型和中间型,染色体数目均为2n=18,基数为x=9,中期染色体主要由中部与亚中着丝点染色体组成。  相似文献   

5.
采用常规压片法,对钠猪毛菜、准噶尔猪毛菜、小药猪毛菜和薄翅猪毛菜等4种新疆猪毛菜属植物的染色体核型进行了分析,并对已报道的12种新疆猪毛菜属植物核型进行了比较.结果表明:(1)钠猪毛菜体细胞染色体数2n=2x=18=12m+6sm,准噶尔猪毛菜、小药猪毛菜体细胞染色体数为2n=2x=18=18m,该3种均属于1A型;薄翅猪毛菜体细胞染色体数为2n=2x=54=50m+2sm+2st,属2A型;(2)12种新疆猪毛菜属植物核型比较结果证明,猪毛菜属植物的染色体基数为9,钠猪毛菜、准噶尔猪毛菜和小药猪毛菜均为二倍体,薄翅猪毛菜为六倍体,钠猪毛菜和准噶尔猪毛菜具有随体.准噶尔猪毛菜、小药猪毛菜、薄翅猪毛菜属植物的核型均属于首次报道.  相似文献   

6.
本文继续报道了薯蓣属(Dioscorea L.)块茎类5个组(sect. Combilium Pr.et Burk.,Sect. Lasiophyton Pr. et Burk., Sect. Opsophyton Uline, Sect. Shannicorea Pr. et Burk., Sect. Enantiophyllum Uline)23个种和变种的染色体数,并对一些分类群进行了讨论。它们都是基数为10的多倍体,是本属进化的类型。 根据染色体数的演化和二倍体种类的地理分布,我们推论我国横断山脉地区可能是薯蓣属的起源中心。  相似文献   

7.
裸蒴属的核型及三白草科四属间系统关系的探讨   总被引:5,自引:3,他引:5  
本文首次报道三白草科裸蒴属中华裸蒴(Gymnotheca chinensis Decne)和白苞裸蒴(G. involucrata Pei)的染色体数目。两个种的体细胞染色体数均为2n=18,染色体基数为x=9。三白草科原始祖先的染色体基数假定为x=11,裸蒴属可能是经非整倍减少演变而来。裸蒴属间期核型属球状或棒状前染色体型。本文根据三白草科染色体研究的结果和现代地理分布格局,结合其他分枝学科的研究资料,对科下四属间的系统发育关系提出了初步假设。  相似文献   

8.
四种风毛菊属植物的核型研究   总被引:14,自引:0,他引:14  
黄运平  尹祖棠   《广西植物》1994,14(4):357-360
本文首次报道产于我国华北地区风毛菊属(SaussureaDC.)4种植物的染色体数目和核型。四个种的染色体数目均是2n=26,都是2倍体。它们的核型是:糠风毛菊(S.Paleata)Zn=2x=26=18m+6sm+2st,属2B型,华北风毛菊(S.mongolica)Zn=2x=26=14m+4sm+8st,属2B型;狭苞凤毛菊(S.dielsiana)Zn=2x=26=8m+12sm+6st,属2C型;银背凤毛菊(S.nivea)2n=2x=26=18m+6sm+2st,属2A型。染色体中均未发现随体。  相似文献   

9.
中国芸苔族植物染色体数目的观察   总被引:6,自引:1,他引:5  
本文报道了在我国分布或栽培的5属、41种和变种的芸苔族植物的花粉母细胞减数分裂期的染色体数,其中15种和变种是新报道。个别种类的数目与以往的报道不完全一致。  相似文献   

10.
本文报道了四川峨眉山、云南点苍山和北京雾灵山产的25种蕨类植物的染色体数目,其中15种的染色体数目和4个种的细胞型是首次记载。此外,还对荚囊蕨属(Struthiote-ris)和水龙骨属(Ppolypodiodes)等属的染色体基数进行了讨论。  相似文献   

11.
New somatic chromosome numbers for nine species eight families and eight gen era in the Sino-Japanese Region are reported here as shown in Table 1. Data of six genera are previously unknown cytologically. The bearings of these new data on the systematics and evolution of the related species, genera or families are discussed as follows: (1) Platycarya strobilacea Sieb. et Zucc. (Juglandaceae). The chromosome number of this species is 2n=24, with a basic number of x=12, which deviates from 2n=32 occurred in Juglans, Carya, Pterocarya and Engelhardtia with the basic number x= 16. The Juglandaceae appears to be fundamentally paleotetraploid, with an original basic number of x = 6 in Platycarya and x-8 in the other four genera, although secondary polyploidy occurs in Carya. Based on the remarkable morphological differences between Platycarya and the rest seven genera of the family, Manning (1978) established two subfamilies: Platycaryoideae for Platycarya and Juglandoideae for the other genera. Iljinskaya (1990), however, recently established a new subfamily: Engelhardioideae for Engelhardtia. Lu (1982) points out that because of a great number of primitive characters occurring in Platycarya, the genus could not be derived from any other extant juglandaceous taxa but probably originated with the other groups from a common extinct ancestor. The present cytological data gives support to Manning′s treatment. We are also in favor of Lu′s supposition and suggest that basic aneuploid changes, both ascending and descending, from a common ancestor with the original basic number x=7, took place during the course of early evolution of the Juglandaceae and led to the origin of taxa with x=6 and 8. Subsequent polyploidy based on these diploids occurred and brought forth polyploids of relic nature today, whereas their diploid progenitors apparently have become extinct. (2) Nanocnide pilosa Migo (Urticaceae). The chromosome number of this Chinese endemic is 2n-24, with a basic number of x=12. An aneuploid series occurs in the Urticaceae, with x--13, 12, I1, 10, 9, 8, 7, etc. According to Ehrendorfer (1976), x = 14, itself being of tetraploid origin, is the original basic number of the whole Urticales, and descending aneuploid changes took place in the early stage of evolution of the Urticaceae and Cannabinaceae. In addition to Nanocnide, x= 12 also occurs in Australina, Hesperonide and Lecanthus, and partly in Chamabainia, Elatostema, Girardinia, Pouzolzia and Urtica. (3--4) Sedum sarmentosum Bunge and S. angustifolium Z. B. Hu et X. L. Huang (Crassulaceae). The former is a member of the Sino-Japanese Region, while the latter is only confined to eastern China. The chromosome number of Sedum is remarkably complex with n=4-12, 14-16…74, etc. S. angustifolium with 2n=72 of the present report is evidently a polyploid with a basic number of x =18 (9?) Previous and present counts of S. sarmentosum show infraspecific aneupolyploidy: n = c. 36 (Uhl at al. 1972) and 2n=58 (the present report). These two species are sympatric in eastern China and are morphologically very similar, yet distinguishable from each other (Hsu et al. 1983) S. sarmentosum escaped from cultivation in the United States gardens exhibited high irregularity in meiosis (Uhl et al. 1972). Uhl (pets. comm. ) suspected strongly that it is a highly sterile hybrid. R. T. Clausen (pets. comm.) found that plants of S. sarmentosum naturalized in the American Gardens propagated by means of their long stolons and broken stem tips, and could not yield viable seeds. Hsu et al. (1983) found that some of the plants of S. sarmentosum and S. angustifolium did yield a few seeds, but other did not. These species are, therefore, by the large vegetatively apomictic. (5) Glochidion puberum (L. ) Hutch. (Euphorbiaceae). The genus Glochidion includes about 300 species, but only eigth species from the Himalayas have been studied cytologically, with n= 36 and 2n= 52, having a basic number of x= 13. The present count for the Chinese endemic G. puberum establishes the tetraploid chromosome number 2n= 64, and adds a new basic number x= 16 to the genus. (6) Orixa japonica Thunb. (Rutaceae). Orixa is a disjunct Sino-Japanese monotypic genus. Out of the 158 genera of the Rutaceae, chromosome numbers of 65 genera have hitherto been investigated, of which 42 genera are with x=9 (66.61%), some with x=7, 8 and 10, and rarely with x=13, 15, 17 and 19. The present count of 2n=34 for O. japonica may have resulted from a dibasic tetraploidy of n=8+9. (7) Rhamnella franguloides (Maxim.) Weberb. (Rhamnaceae). The chromosome number of this member of the Sino-Japanese Region is 2n= 24. with a basic number of x= 12. The basic number x= 12 also occurs in Hovenia, Paliurus, Sageretia, Ceanothus and Berchemia. Hong (1990) suggested that x= 12 in Rhamnaceae may be derived from descending aneuploidy of a paleotetraploid ancestor. (8) Sinojackia xylocarpa Hu (Styracaceae). The chromosome number of this rare Chinese endemic is 2n= 24, with a basic number of x =12, which is identical with that in Halesia and Pterostyrax, but deviates from that in Styrax (x=8). The basic number x=8 in the Styracaceae may be derived from the original basic number x=7 by ascending aneuploidy in the early stage of evolution of the family, and x=12 may be derived from polyploidy. (9) Thyrocarpus glochidiatus Maxim. (Boraginaceae). The chromosome number of this Chinese endemic species is 2n=24, with a basic number of x=12. An extensive aneuploid sequence of x = 4-12 occurs in the Boraginaceae, of which x = 8, 7 and 6 are the most common. The basic number x=12 also occurs in Cynoglossum and Mertensia. It is evident that aneuploid changes, both descending and ascending, from an ancestor with x = 7, have taken place in the primary phase of evolutionary diversification of the Boraginaceae, and subsequent polyploidy has given rise to x=15, 17 and 19 in a few genera (e. g. Amsinskia and Heliotropium). The origin of x=12 is not certain. Either it be a result of ascending aneuploidy, or a product of polyploidy on the basis of x = 6. The present authors are in favorof the latter.  相似文献   

12.
竹叶吉祥草(鸭跖草科)的核型研究   总被引:1,自引:0,他引:1  
杨亲二  罗毅波  洪德元   《广西植物》1994,14(2):170-173
本文对鸭跖草科的竹叶吉祥草(Spatholirionlongifolium(Gagnep.)Dunn)进行了染色体研究.其染色体大型,数目为2n=20;核型公式为2n=4sm+14st+2t(sat).为首次报道。这支持了竹叶吉祥草属和竹叶子属是两个亲缘关系较近,但同时又是两个分明不同的属的观点。  相似文献   

13.
Chromosome counts are reported for 32 taxa (31 species and 1 subspecies) belonging to 10 genera of Commelinaceae from seven African and Asiatic countries. Counts for 13 species and 1 subspecies are recorded for the first time. Published chromosome numbers for Anhicopsis and Polyspatha are confirmed. It is suggested that Pdisota, Pollia and Stanfieldidla each has a single basic number (x = 20, 16 and 11, respectively). The known cytological diversity in Floscopa is extended. The third continental African species of Coleolrype is found to have the same chromosome number (2n = 36) as the other two. The preponderance of the basic number x = 15 in Commelina is supported. The uncommon basic number x = 13 is reported in four taxa of Cyanotis together with karyotypic differences. The basic number x = 6 is found in a second species of Murdannia . Karyotypic data in addition to chromosome numbers are presented for 24 of the 32 taxa investigated. Karyotypes are found to be useful in assessing relationships in the family, and evolutionary trends in the karyotype are noted.  相似文献   

14.
新疆多年生小麦族植物染色体数的观察   总被引:6,自引:0,他引:6  
孙根楼  颜济  杨俊良   《广西植物》1990,10(2):143-148
本文对1987年采集于新疆的多年生小麦族(Triticeae Dum. )属种进行了细胞学观察。该地区多年生小麦族各属种的染色体数目变化范围是从2n=14到2n=84,前者主要存在于大麦属(Hordeum)、新麦草属(Psathyrostachys),而后者全部集中于赖草属(Leymus).其中染色体数目为2n=28和2n=42的频率最高,主要存在于鹅冠草属(Roegneria)和披碱草属(Elymus)。Roegneria gobicola, Roegneria kuqaensis, Roegneria tahelacona, Roegneria zhoasuensis的染色体数为首次报道。  相似文献   

15.
新疆、青海和四川等地区小麦族植物的细胞学观察   总被引:7,自引:1,他引:6  
本文对采集于新疆、青海和四川等地的小麦族(Triticeae Dumortier)10属、52种、370份种子材料进行了细胞学观察。该地区小麦族各属种的染色体数目变化范围是从2n=14到2n=84,前者主要存在于大麦属(Hordeum)、新麦草属(Psathyrostachys)和黑麦属(Secale),而后者全部集中于赖草属(Leymus)。其中染色体数目为2n=28和2n=42的类型出现的频率很高,大多存在于鹅观草属(Roegneria)和披碱草属(Elymus)。除个别种内存在不同倍性的细胞型外,绝大多数种的染色体数目非常稳定。在所有的样本中均没有观察到具非整倍体和B-染色体的材料。  相似文献   

16.
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 Sprague 2n=16, x=8. The chromosome counts of three ranunculaceous genera are reported for the first time. 2. The morphylogical, palynological and cytological date in relation to the systematic postition of Asteropyrum, Kingdonia and Calathodes within the family Ranunculaceae are diseussed and resulted in following conclusions: (1). On the basis of the basic number x=8 in Asteropyrum, it is further confirmed that this genus is distinct from the r elated genera such as Isopyrum, Dichocarpum 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 different from coptis in the chromosome numbers (T-type), pantocolpate pollens, united carpels and the dorsi-ventral type of petioles. In view of these fundamental morphological 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 unilacunar of Kingdonia may be derived from the trilacunar. On the basis of the chromosome 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 characteristics 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 pending 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.9841  相似文献   

17.
Rubus is a taxonomically difficult group and cytological data are expected hopefully to gain insight into the relationships of the genus. In this study the chromosome numbers and karyotypes of 18 taxa from sect. Idaeobatus and 10 taxa from sect. Malachobatus were investigated. Among them, the chromosome numbers of 10 taxa and karyotypes of 26 taxa were reported for the first time and mixoploidy was observed new in the genus. The chromosomes are small in size with a length of less than 3 µm and metacentric (about 90%) or submetacentric. All taxa have karyotypes of “1A” except R. cockburnianus, R. innominatus and R. ellipticus var. obcordatus, which have karyotypes of “2A”. No aneuploids were found in all the 28 taxa studied. Plants of sect. Idaeobatus have diploids with 2n=2x=14, except R. idaeopsis (2n=3x=21) and R. parvifolius (A mixoploid of 2n=2x=14 and 2n=4x=28). However, plants of sect. Malachobatus have tetraploids with 2n=4x=28, except for R. buergeri with 2n=8x=56. In addition, conspicuous karyotype differences existed within the 18 taxa belonging to 11 of 7 subsections in sect. Idaeobatus, and the differences between some species within subsections are greater than that between subsections, while uniform karyotypes within subsections and variable karyotypes between subsections were observed in six of 13 subsections in sect. Malachobatus represented by 10 taxa. Systematic values of the cytological data were discussed for some cases when applicable to the two sections.  相似文献   

18.
Reported in the present paper are chromosome numbers and karyotypes of three genera of the Gesneriaceae, i.e. Ancylostemon Craib. , Briggsiopsis (Franch.) K. Y. Pan and Lysionotus D. Don. The former two genera are endemic to China. The karyotype of Ancylostemon aureus (Franch.) Burtt is formulated as 2n = 34 = 20m(1sat) + 14sm, with the same chromosome number as its allied species A. convexus Craib. This species is characterized by the interphase nucleus of complex chromocenter type and the proximal type of chromosomes in the mitotic prophase. The chromosome number of the monospecific genus Briggsiopsis is 2n = 34, the same as the lowest chromosome number reported in Briggsia. The karyotype of Briggsiopsis, which is formulated as 2n = 25m + 6sm + 3st, also seems to be primitive among the species of the two genera. Briggsiopsis is characterized by the interphase nucleus of simple-complex chromocenter type and the interstitial-gradient type of chromosomes in the mitotic prophase. The chromosome number of Lysionotus carnosus Hemsl. is the lowest reported in this genus. Its karyotype is formulated as 2n= 30 = 21m + 5sm + 3st + lt. Lysionotus serratus var. pterocaulis, with the karyotype being formulated as 2n= 32 = 2lm + 10sm + lt, has the same chromosome number as var. serratus. These two species show a remarkable differentiation of karyotypes and are characterized by the interphase nuclei of simple-complex chromocenter type and the gradient type of chromosomes in the mitotic prophase. _ .  相似文献   

19.
A karyotypic study was performed on 19 Echinops species in Fars Province, Iran. The taxa revealed chromosome counts of 2 n = 28, 30, 32 and 34. Somatic chromosome numbers of 18 species are reported for the first time. Using somatic chromosome number as a criterion for section delimitation, the transfer of E. gedrosiacus, E. cyanocephalm and E. sojakii from Sect. Oligolepis to Sect. Ritropsis is suggested. Differences in basic chromosome numbers point towards the possible role played by centric fusion/fission in the karyotypic evolution of the genus. The Karl Pearson coefficient of correlation and principal components analysis indicated the occurrence of structural changes in chromosomes. The species occupied classes 1A, 2A & 2B of Stebbins' karyotype classification, indicating the presence of a primitive symmetrical karyotype in the genus.  相似文献   

20.
A cytotaxonomic study was made of 10 fern species belonging to 7 genera of Polypodiaceae from Yunnan, China. Seven new records (including one cytotype) were reported in this paper. The putative reproduc-tive manners were inferred from cytological characters and spore counting. The chromosome numbers were 2n=70 in Polypodiastrum mengtzeense, Lepisorus bicolor; 2n=72 in Polypodiode amoena, P. wattii, L. mac-rosphaerus, Lepidogrammitis rostrata, Drymotaenium miyoshianum, Tricholepidium maculosum, Phymatopteris oxyloba; and 2n=108 in P. trisecta. The reproductive type in P. trisecta is triploid apogamous while it is of the sexual diploid reproductive type in the other species of the genus Phymatopteris. Based on our study and previous data, the significance of chromosome number in phylogenetic study was discussed.  相似文献   

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