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On the basis of cytological data and with consideration of a wide literature, the taxonomy of Liliales as delimited by Hutchinson are represented. A review about phylogeny of Liliaceae in different systems is given. In the main part a great number of tribes of Liliaceae are treated with regard to delimitation, affinities and evolution. Further a cytological assessement of evolution and interrelationships of different families of Liliales with Liliaceae were indicated. Ultimately the lines of evolution of Liliaceae were debated. Especially e. g. the following more important conclusions were outlined: The primitive tribe Heloniadeae might have descended from Juncaginaceae. The potentiality of Asphodeleae as the progenitor of different tribes of Liliacae has been confirmed. The tribe Ophiopogoneae is quite homogeneous, whereas the tribe Hemerocalleae has been indicated as an unnatural group, and some genera are transfered under Agavales. The origin of Amaryllidaceae from Tulipeae and Hemerocallideae is confirmed. Agapantheae is an advanced representative of the subfamily Allioideae of Amaryllidaceae. In Polygonatum the “latifolium” type of “alternifolia” represents the primitive state with 9 or 10 as basic chromosome number. The midtertiary origin of Smilacina has been supported. Disporum of pleistocene origin is likely to have given rise to Polygonatum through diminution in chromosome size and asymmetry on the one hand and Smilacina on the other, with increase in asymmetry. Asiatic species of Disporum representing the most primitive form and have been reponsible for the evolution of the American species of Disporum and in another line of Aspidistreae, Convallarieae, and Peliosantheae. The creation of the tribes Dianelleae and Veratreae is supported. With the exclusion of Calochortus and Lloydia, Tulipeae would represent a homogeneous grouping. In Scilleae, Scilla sibirica with n = 6 chromosomes represents a primitive form. Muscari is to be separated into three genera. The Tulipeae should be divided into several assemblages which represents origin from a common stock.  相似文献   

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At present there is karyological information on ca 10% of the species and ca 30% of the genera of the Apocynaceae. Basic numbers of x = 6, 8, 9, 10, 11, 12, 16, 18, 20, 21 and 23 have been assessed. Of these x = 11 is primitive, occurring in ca 60% of the genera. Those of x = 6, 8, 9 and 10 have evolved by reduction, and x = 12 by increase from x = 11. In the subtribe Secondatiinae however, x = 12 is most likely the result of doubling x = 6. The numbers x = 16, 18 and 20 are likewise doubles of x = 8, 9 and 10 respectively. Those of x = 21, 23, and in one case, x = 20 are probably aneuploid products of doubles of x = 11. The two larger subfamilies, Plumerioideae and Apocynoideae have the basic numbers x = 8, 9, 10 and 11 in common and are not separable on the basis of chromosomal evidence. The third small subfamily Cerberoideae is more homogeneous according to basic number, i.e. x = 10 and 20. Most genera are characterized by a constant basic number, but some have two basic numbers; these clearly are cases of infrageneric aneuploidy. Based on records in the literature two closely related generaApocynum andTrachomitum appear to be characterized by a basic number of x = 8 as well as x = 11. This conflicting situation should be clarified by further karyological research. From the level of subtribe onwards some taxa have one basic number, but others are characterized by two or more numbers. The occurrence of similar basic numbers in different phylads of the family is considered to be the result of similar chromosomal evolution mechanisms. Approximately 22% of the investigated species are polyploid. Intrageneric polyploidy occurs with a frequency of about 12.5% and infraspecific polyploidy with less than 4%. The karyotypes observed are symmetrical: the chromosomes within a karyotype are similar in length with primary constrictions usually in a median position. In the Tabernaemontaneae however, it was observed that the karyotypes comprise one pair of distinctly heterobrachial chromosomes in addition to the metacentric ones. This tribe is also characterized by chromosomes which are relatively long. Most genera of the African continent, which are well known regarding their chromosome number, are characterized by x = 11. Exceptions areStrophantus (x = 9) with a mainly tropical African distribution. Two other genera with derived numbers, i.e.Gonioma with x = 10 andPachypodium with x = 9, occur in southern Africa and Madagascar. The genera with a non-African distribution are less known for their chromosome number. However, the available evidence suggests that evolution of derived numbers has occurred more frequently outside Africa than on this continent.  相似文献   

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A modification of the general system of classification ofCalliphoridae is proposed in this report. Information about the chromosome complements of about 90 species is provided including references to the earlier literature on chromosomes of this family. With one exception all species studied by us or by earlier investigators have 2n=12. The total complement length of 556 complements from 83 species averaged 66.4 μ. Most species have a short heteromorphic sex pair but the size and morphology vary considerably and one species,Hemipyrellia fernandica, seems to have a quadrivalent sex-chromosome complex in a 2n=14 complement. The autosomal pairs vary in both length and arm ratios between the species but seem to be more stable than the sex chromosomes. Only minor variations were found between different collections of the same species except for two collections ofCalliphora croceipalpis. Although presently available data on the chromosomes of Diptera species suggest that increases in total complement length accompany evolutionary progress, no such general trends were obvious in either the total complement lengths or chromosome morphology, either within or between the tribes ofCalliphoridae. Thus the karyotypical reorganizations in the family have apparently not been directly associated with changes in the general morphological features of the adults which may have responded in these respects more extensively to genetic mutations.  相似文献   

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The karyotypes of somatic cells of three species in Ferula L. (Umbelliferae) from China are reported for the first time in this paper. F. licentiana Hand. -Mazz., endemic to China, has the karyotype formula of 2n= 22= 14m+ 2sm+ 6st( 2SAT), which consists of nine pairs of L chromosomes (the relative length > 8.0) and two pairs of M chromosomes (the relative length, 8.0- 6.0). The index of the karyotypic asymmetry (AS. K%) is 36.36%, and the karyotype belongs to 2A (Stebbins 1971). F. licentiana var. tunshanica (Su) Shan et Q. X. Liu has the karyotypic formula of 2n=22= 14m+ 8st(2SAT), and the other characters of karyotype are very similar to those of F. licentiana. The karyotypic formula of F. bungeana Kitag. is 2n=22= 12m+ 6sm+ 2st. There are 8 pairs of L chromosomes and 3 pairs of M chromosomes in this karyotype. The AS.K% is 45.45% and thus the karyotype is rather symmetrical (2A). Based on above data, F.licentiana var. tunshanica may be treated as a variety of F.licentiana and F.bungeana be separated from Subgen. Peucedanoides. According to our study and available data, we consider that the basic chromosome number of Ferula is x= 11. The karyotypic evolution of 11 species in the genus from China is analysed. All species are grouped into 5 groups based on the cluster analysis of chromosome data: I.F. akitschensis B. Fedtsch. ex K.-Pol.; II. F. lapidosa Korov., III. F. bungeana. The above-mentioned three species belong to Subgen. Peucedanoides in classification. IV. This group is divided into two subgroups: (1) F. syreitschikowii K.-Pol. and F. ovina (Boiss.) Boiss.; (2) F. lehmannii Boiss., F. licentiana, F. licentiana var. tunshanica, F. Kirialovii Pimen. and F. sumbul (Kauffm.)Hook. f., in which F.lehmannii belongs to Subgen. Merwia, F. syteritschikowii to Subgen. Narthex and the rest five species to Subgen.Peucedanoides. V. F.caspica M. Bieb. of Subgen. Doromatoides.  相似文献   

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中国蜘蛛抱蛋属的细胞分类学研究Ⅱ   总被引:5,自引:2,他引:5  
王任翔  李光照  郎楷永  韦毅刚  刘演   《广西植物》2000,20(2):138-143+193
报道了 11种蜘蛛抱蛋属植物的染色体数目和核型。结果如下 :伞柱蜘蛛抱蛋 ** ,2 n=36 =2 0 m+6 sm(2 sat) +10 st,属 2 C型 ;辐花蜘蛛抱蛋 ** ,2 n=38=2 2 m+6 sm(2 sat) +10 st,属 2 C型 ;棒蕊蜘蛛抱蛋 **,2 n =36 =18m +8sm (2 sat) +10 st,属 2 C型 ;柳江蜘蛛抱蛋 **,2 n=38=2 0 m +6 sm(2 sat) +12 st,属 2 C型 ;小花蜘蛛抱蛋 ,2 n=38=16 m +4sm +8st (2 sat) +10 t,属 3C型 ;线叶蜘蛛抱蛋 ** ,2 n=36 =2 0 m(2 sat) +16 st,属 2 C型 ;罗甸蜘蛛抱蛋 ,2 n=38=16 m+6 sm(2 sat) +16 st,属 2 C型 ;四川蜘蛛抱蛋 ,2 n=38=2 4 m +4sm+10 st (2 sat) ,属 2 C型 ;广东蜘蛛抱蛋 ,2 n=36 =18m +2 sm(2 sat) +16 st,属 2 C型 ;洞生蜘蛛抱蛋 **,2 n=36 =18m +2 sm(2 sat) +14st+2 t,属 2 C型 ;大花蜘蛛抱蛋 ,2 n=36 =16 m+6 sm(2 sat) +14st,属 3C型。其中棒蕊蜘蛛抱蛋、柳江蜘蛛抱蛋、线叶蜘蛛抱蛋和洞生蜘蛛抱蛋的染色体数目和核型以及广东蜘蛛抱蛋的核型均为首次报道。  相似文献   

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贵州产蜘蛛抱蛋属植物的细胞分类学研究   总被引:1,自引:0,他引:1  
报道了6种贵州产蜘蛛抱蛋属植物的染色体数目和核型,并与其相应近缘种对比,联系植物的外部形态特征,探讨核型结构与形态特征的相关性.发现1个种的染色体数目为2n =36,5个种的染色体数目为2n =38,核型公式分别为:平塘蜘蛛抱蛋(Aspidistra pingtangensis),2n =38 =20m +4sm(2sat) +14st;荔波蜘蛛抱蛋(A.liboensis),2n =38 =22m(2sat)+4sm+ 12st;赤水蜘蛛抱蛋(A.chishuiensis),2n =38 =22m(2sat)+8sm +8st;伞柱蜘蛛抱蛋(A.fungilliformis),2n =36=18m (2sat) +4sm+ 14st;四川蜘蛛抱蛋(A.sichuanensis),2n =38 =22m (2sat) +4sm +12st;丛生蜘蛛抱蛋(A caespitosa),2n =38 =20m +6sm(2sat) +12st.核型类型都为2C型.其中平塘蜘蛛抱蛋、荔波蜘蛛抱蛋和赤水蜘蛛抱蛋的染色体数目和核型均为首次报道.研究结果表明,该属植物的核型结构与外部形态特征具有一定的相关性,细胞分类学研究可以为该属植物起源进化研究以及自然分类鉴定提供一定的依据.  相似文献   

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Various species ofTaxodiaceae were selected for chromosome studies to indicate cytotaxonomic and phylogenetic relationships. Point dispersal patterns of diagrammatic presentations of the species' karyotypes, rather than marker chromosomes, were found to be the most significant cytotaxonomic characteristic in indicating phylogenetic relationships. Karyotypic evolution inTaxodiaceae appears to occur by unequal reciprocal translocations followed by pericentric and paracentric inversions. Cytotaxonomic relationships among species generally correspond to the phylogenetic relationships withinTaxodiaceae indicated by classical taxonomic classification. Presence and types of marker chromosomes may have the potential to indicate relationships between different coniferous families.  相似文献   

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Cytotaxonomical investigations on 11 species from the Western Himalayas show that 8 are diploid and the remaining tetraploid. The numbers for three species are new.P. prescottianum (2x) andP. thomsoni (4x), andP. stimulans (2x) andP. acanthophyllum (4x) are closely related but distinct species pairs.  相似文献   

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Cytotaxonomic investigations of the autumn-flowering squills, Prospero autumnale (L.) Speta ≡ Scilla autumnalis L., Prospero obtusifolium (Poir.) Speta ≡ Scilla obtusifolia Poir., Barnardia numidica (Poir.) Speta ≡ Scilla numidica Poir., and Hyacinthoides lingulata (Poir.) Rothm. ≡ Scilla lingulata Poir. were performed in 20 populations from northern Algeria located between Tipasa and La Vieille Calle. Various chromosome numbers were found, including a new cytotype, 2n = 8, for the flora of Algeria, concerning plants identified as Prospero obtusifolium (Poir.) Speta [including P. fallax (Steinh.) Speta = S. autumnalis L. ssp. fallax (Steinh.) Batt.]. The numbers 2n = 14, 28, and 42 correspond, respectively, to diploid, tetraploid, and hexaploid levels of P. autumnale s.l. [including P. pulchellum (Munby) Speta ≡ Scilla pulchella Munby = S. autumnalis var. pulchella (Munby) Batt.], with x = 7. The cytotypes of Barnardia numidica (Poir.) Speta with 2n = 18 and Hyacinthoides lingulata (Poir.) Rothm. with 2n = 16 chromosomes were confirmed.  相似文献   

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J. W. F. Reumer 《Genetica》1984,65(2):149-158
A hypothetical phylogeny is presented for the genus Cryptocoryne (Araceae, Cryptocoryninae). This scheme is based on both geographical and cytological data. Therefore the geography of S. E. Asia, the distribution of the various base numbers and the possible relationships between the base numbers are discussed.In the resulting phylogeny the various base numbers of Cryptocoryne (and the one of Lagenandra) are thought to have been derived from a hypothetical primary base number x1=9. As a consequence of the scheme, Cryptocoryne is assumed to have a diphyletic character.  相似文献   

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Cytotaxonomy of the triatominae (Reduviidae: Hemiptera)   总被引:1,自引:0,他引:1  
The chromosome number and meiotic cycle of 20 species of Triatominae have been investigated. In the male, there are five types of chromosome complement: 20+XY, 20+X1X2Y, 20+X1X2X3Y, 18+XY and 22+XY.The cytological data suggest that the type number for the subfamily is 22 (20+XY). In the hybrids: Triatoma barberi () and T. protracta (), anomalous behavior of certain chromosomes has been observed. Phylogenetic relationships based on chromosome evidence in the subfamily have been discussed. It is suggested that fragmentation is the major factor for chromosome evolution in the group.  相似文献   

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The generic placement of Prenanthes faberi Hemsl. (Compositae–Cichorieae) has long been a controversial matter. Recent molecular phylogenetic analyses indicate its inclusion in the genus Faberia Hemsl. The present cytological investigation shows that this species has a chromosome number of 2n = 34 and a fairly symmetric karyotype consisting of 26 median centromeric (m) and 8 submedian centromeric (sm) chromosomes varying in length between 1.72–4.20 μm. The karyological characters of P. faberi are remarkably consistent with those reported previously in species of Faberia. The transference of this species to Faberia is strongly supported.  相似文献   

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