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1.
山白树属及其近缘属聚类分析   总被引:1,自引:0,他引:1  
运用系统聚类分析法,对山白树属及其近缘属进行定量分析,结果表明山白树属与牛鼻栓属亲缘关系密切,可组成一族,该族与蚊母树族有着较近的亲缘。  相似文献   

2.
俞藤属—葡萄科一新属   总被引:2,自引:0,他引:2  
作者在研究中国葡萄科植物过程中发现分布于中国亚热带、尼泊尔和印度卡西山区一些植物种自成一类,与葡萄科现有属的定义不符,命名为一新属-愈藤属(YuaC.L.Li)。文中讨论了它与爬山虎属(Parthenocissus Planch.)、崖爬藤属(TetrastigmaPlanch.)、乌蔹莓属(CayratiaJuss.)和蛇葡萄属(Ampelopsis Michx.)的区别,并在野外和栽培条件下观察了某些重要属级鉴定性状在个体发育过程中的表现,以证明其可靠。为了正确鉴定这个属和种类,给出了包括这些属在内的国产葡萄科植物分属检索表和该属的分种检索表,最后,讨论了俞藤属的地理分布及其意义。  相似文献   

3.
综述了番茄属和茄属的属间细胞杂交研究进展,并对植物细胞杂交研究的发展和存在问题进行了讨论。  相似文献   

4.
中国新记录属—皮司霉属   总被引:1,自引:0,他引:1  
  相似文献   

5.
6.
菊属与亚菊属属间杂种的鉴定及其分类学意义   总被引:6,自引:0,他引:6  
通过有性杂交的方法获得了栽培菊花“奥运火炬”Dendranthema×grandiflorum“Aoyunhuoju”和亚菊属Ajania矶菊A.pacifica的属间杂种。形态学、细胞学以及RAPD分子标记鉴定表明22个杂种为真正的属间杂种,成功地将矶菊的某些性状(叶色)转移到栽培菊花中,但同时也掺入了某些不良性状。杂种的叶色、叶形、花色、开花枝的分枝性和花期等性状均介于双亲之间,边缘舌状雌花大小、数量和形态不一;杂种根尖染色体数目正常(2n=72),花粉母细胞减数分裂基本正常。矶菊与栽培菊花属间杂交的成功以及杂种减数分裂染色体行为正常表明两者亲缘关系较近,从而推测菊属Dendranthema与亚菊属之间的亲缘关系可能较近。  相似文献   

7.
8.
悬钩子属和蔷薇属的新植物   总被引:2,自引:0,他引:2  
俞志雄 《植物研究》1991,11(1):53-54
本文发表了山莓两个新变型和小果蔷薇一新变型,即粉红山莓Rubus corchorifolius L.f.f.roseolus Z.X.Yu、重瓣山莓R.cor-chorifolius L.f.f.Hemi semiplenus Z.X.Yu,还有重瓣小果蔷薇Rosa cymosa Tratt.f.plena Z.X.Yu et G.Z.Liu。  相似文献   

9.
栓菌属和它的亲缘属属界划分的研究   总被引:1,自引:0,他引:1  
栓菌属(Trametes) 自Fries(1835)建立迄今已有近150年的历史。Fries(1835),Patouillard(1900),Kotlaba & Pouzar(1957),的工作代表了对本属研究的三个比较重要的发展阶段。许多分类学家都认为栓菌属是多孔菌科(Polyporaceae,Basidiomycetes)中最混乱、最不易划清属间界限的一个类群。研究清楚这一属和它的亲缘属的属界以及它们之间的相互关系是研究多孔菌科分类中十分重要的课题。作者多年来在研究这一类群的过程中,常常遇到属界不清,它们之间的相互关系也不易搞清楚等问题。从文献中可以看出,有的种类似乎可以随便地从一个属转移到另一个属,正确与否不易确定。因此,感到搞清楚本属的属界是十分重要的。作者即是在这一情况下进行这一课题研究的。首先搞清楚栓菌属的发展历史,各分类学家对它的不同概念,最后提出作者对本属的概念。然后再搞清楚各亲缘属的属界与其相互关系。凡是作者承认的属都提出自己的概念。  相似文献   

10.
张颖  周永红  张利  张海琴  杨瑞武  丁春邦 《遗传》2006,28(4):449-457
对鹅观草属、披碱草属、猬草属和仲彬草属23个物种和1份外类群共24份材料进行了细胞质基因组PCR-RFLP分析。3个叶绿体和3个线粒体通用引物扩增出的片段,用15种限制性内切酶对其进行酶切。在47种引物/酶组合中,获得329条DNA片段,其中304条具有多态性,占92.4%。结果表明鹅观草属、披碱草属、猬草属和仲彬草属材料存在属间和种间多态性,遗传相似系数较高。聚类分析显示仲彬草属单独聚为一类,鹅观草属R. grandisR. aristiglumisR. elytrigioidesR. alashanicaR. magnicaespes聚为一类,R. caucasicaR. ciliarisR. amurensisR. japonensis聚在一起,5个披碱草属材料、3个猬草属材料和1个鹅观草属物种R. kamoji聚为一类。这些结果与前人对其进行的RAPD和RAMP分析的结果基本一致。仲彬草属作为属分类等级处理是恰当的,对于鹅观草属、披碱草属和猬草属的系统地位和一些物种的分类处理,有待进一步研究。  相似文献   

11.
Karyomorphological observations were carried out on three genera belonging to the Saururaceae and four genera of the Piperacea. All of the genera of Saururaceae show the same karyomorphological characteristics from interphase to metaphase in the somatic cell divisions. However there are two types of the karyomorphology in Piperaceae, i) the first type observed inPiper, Pothomorphe andZippelia, and ii) the second type inPeperomia. Each group corresponds to Thorne's two subfamilies (1974, 1976), Piperoideae and Peperomioideae. The basic chromosome numbers of the genera are confirmed or newly proposed as follows:Saururus x=11,Houttuynia x=12,Anemopsis x=22 (Saururaceae),Peperomia x=11,Piper andPothomorphe (=Heckeria) x=13,Zippelia x=19 (Piperaceae). The relationships of these basic chromosome numbers are presumed to be as shown schematically in Fig. 4. The original basic chromosome number of the common ancestral stock of Saururaceae and Piperaceae is presumed to be x=11.  相似文献   

12.
The pollen morphology of 25 species and 10 genera of Piperales (Chloranthaceae, Piperaceae and Saururaceae) has been examined under light microscope, of which 7 species were observed under scanning electron microscope and 1 species, Hedyosmum orentale Merr. & Chun transmision electron microseope. Three principal types of pollen were found: anasulcate (mostly) (sometime trichotomosulcate), inaperturate (partly) and multicolpoidate (partly). The present article has discussed the palynological data mainly in relation to the classification and the systematic position of Cbloranthaceae and also deals with the systematic position of the order Piperales. The present author agrees to put the family Chloranthaceae into the order Piperales. Because this family differs from Piperaceae and Saururaceae in pollen morphology, therefore, Chloranthaceae should raise to the level of suborder. Among three families of the order Piperales, the present author considers Chloranthaceae to be the most primitive family, on account of the following reasons: 1. The family Chloranthaceae shows the characteristics of primitive entomophilous plants in the sculpture of exine, while in the other two families, Piperaceae and Saururaceae, their exine is almost smooth and represents wind-pollenated plants; 2. Pollen of the family Chloranthaceae are larger than those of Piperaceae and Saururaceae; 3. The fossil pollen Clavatipollenites has been proved to be one of the most primitive angiosperms on the earth, that it is known, it occurred in the early Cretaceous, and at that time ferns and gymnosperms were predominant, while the Chloran- thaceae has already existed at that time; 4. Sarcandra of Chloranthaceae possesses the characters of a vesselless secondary xylem and a delayed development of embryo. Thus, Chloranthaceae would be considered as the most primitive family in the order Piperales. The systematic position of the order Piperales is also discussed. Itutehinson makes a point that order Ranales is more primitive than Piperales, and his system is arranged in the following order: Ranales → Piperales → to climax family Chloranthaceae. This view-point, however, is net supported by the palynological data. Pollen morphology shows that Piperales is more primitive than Ranales, because the pollen in Piperales possess the ancient aperture type of Pteridospermes, i.e., the type of anasulcate aperture is prevailing in Piperales, moreover, pollen grains of Ranales are mainly tricolpate type, and tricolpate pollen is a characteristic of typical angiosperms. In addition, the Piperales possesses a series of characters that are common among monocots, but rare among dicots. As the divergence between dicer and monocot took place in the early Cretaceous, their ancestor possesses common chararcters both of dicots and monocots while the extant Piperales still possess many characters of monocots that indicate it is much nearer to the point of divergence, and it explains that the Piperales is closely related to the ancestor of monocots and dicers Piperales, therefore, is more primitive than Ranales.  相似文献   

13.
Zippelia begoniaefolia Bl., a monotypic species having characteristics of both Piperaceae and Saururaceae, has racemes of about 20 small flowers lacking a perianth, each with six free stamens and a four-carpellate syncarpous gynoecium. The inflorescence apical meristem initiates bracts acropetally and helically, each of which subtends a later initiated single floral apex; there are no “common” primordia. The six stamens are initiated as two lateral pairs and two solitary successive primordia, the latter two opposite in median sagittal positions. Four carpel primordia are initiated as a lateral pair and two successively initiated in the median sagittal plane. This order of organ inception is unique among Piperaceae and Saururaceae. Intercalary growth below carpellary attachment raises them up on a common cylindrical base that becomes the syncarpous ovary, covered with unique glochidiate hairs and containing a single basal ovule. The free portions of the carpels become the reflexed papillate stigmas. The floral vascular system has a single bundle at base that branches to supply the bract and flower traces. The floral vasculature is similar but not identical to that of Saururus (Saururaceae) and some Piper species (Piperaceae). Plesiomorphic character states of Zippelia that are shared with Saururus include hypogyny, free stamens, cleft stigma, and a similar floral groundplan. Synapomorphies, derived shared character states that unite Zippelia with Piperaceae, include syncarpy, solitary ovule, basal placentation, fused ventral carpellary bundles, and a double vascular cylinder in the stem. Cladistic analysis aligns Zippelia with Piperaceae because they share apomorphies, and because Zippelia shares only plesiomorphies with Saururus.  相似文献   

14.
裸蒴属的核型及三白草科四属间系统关系的探讨   总被引:8,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   

15.
The phylogenetically ambivalent monotypic genus Lactoris presents sympodial (determinate) branching, as a terminal flower is present on each main branch. The synflorescence is thyrsoid. Partial inflorescences are rhipidia with up to three flowers. The ochrealike stipule is formed by the fusion of two lateral stipules, which forms an adaxial ligule-like structure and a two-flanked leaf sheath that encircles the parental axis. The leaf sheath elongates with the growth of the preceding internode. Although sympodial growth and a sheathing leaf base are present in all Piperales (Aristolochiaceae, Lactoridaceae, Piperaceae, and Saururaceae), the presence of stipules is confined to Lactoris, Saururaceae, and some Piperaceae. These characters are consistent with the placement of Lactoris within Piperales, although its phylogenetic position within the order remains equivocal, except for the possible sister group relationship suggested by the presence of cymose inflorescences in both Lactoris and Aristolochiaceae.  相似文献   

16.
Medullary bundles of Piperaceae resemble those of Ranunculaceae. The nature of tracheary elements of primary xylem suggests that Houttuynia cordata (Saururaceae), Piper cubeba (Piperaceae) and Chloranthus officinalis (Chloranthaceae) are of lower evolutionary status than others. Among these three, P. cubeba shows stratification of secondary xylem, a specialized character. Lateral wall of metaxylem tracheary elements and distribution of bundles of Peperomia, suggest their primitive status and distinctness, supporting separation of "Peperomiacea:" (of NOVAK). Piper cubeba, Houttuynia and Chloranthus bear one important Ranunculaceous character: scalariform perforation in primary vessels. Primitive species of Peperomia carry probably another Ranunculaceous character, i.e., many circles of medullary bundles. Shape and pattern of vascular bundles of Piper cubeba, Houttuynia and Chloranthus are similar. Other species of Piper show modifications. Peperomia represents another distinct pattern.  相似文献   

17.
三白草科花部发育及其系统学意义   总被引:9,自引:2,他引:7  
本研究从比较三白草科属间小花个体发育及分析花器官数量变异入手,探寻花器官在发生顺序、数目变化及排列方式等方面的演化趋势,揭示系统发育在个体发育中一定程度重现的事实及属间的进化关系。结果简述如下:首先,雄蕊和心皮发生顺序由中部优先演化到两侧优先。其次,由于远中雄蕊和心皮经历了从发育延迟、生长减缓到最终消失的历程,中部雄蕊和心皮由成对演化为单生。此外,两侧生雄蕊对由各自独立的原基发生演化到共同原基发生或减化为1枚,假银莲花属近中1枚雄蕊原基二裂成1对,蕺菜属3枚心皮发生于一环状共同原基等,都是该科花器官演化的重要事实并可归结为融合、减化和复化的结果。文章根据花器官的演化趋势及过渡类型的剖析,论述了三白草科属间的系统进化关系。  相似文献   

18.
Piperales represent the largest basal angiosperm order with a nearly worldwide distribution. The order includes three species rich genera, Piper (ca. 2000 species), Peperomia (ca. 1500-1700 species), and Aristolochia s. l. (ca. 500 species). Sequences of the matK gene and the non-coding trnK group II intron are analysed for a dense set of 105 taxa representing all families (except Hydnoraceae) and all generic segregates (except Euglypha within Aristolochiaceae) of Piperales. A large number of highly informative indels are found in the Piperales trnK/matK dataset. Within a narrow region approximately 500 nt downstream in the matK coding region (CDS), a length variable simple sequence repeat (SSR) expansion segment occurs, in which insertions and deletions have led to short frame-shifts. These are corrected shortly afterwards, resulting in a maximum of six amino acids being affected. Furthermore, additional non-functional matK copies were found in Zippelia begoniifolia, which can easily be discriminated from the functional open reading frame (ORF). The trnK/matK sequence data fully resolve relationships within Peperomia, whereas they are not effective within Piper. The resolution contrast is correlated with the rate heterogeneity between those lineages. Parsimony, Bayesian and likelihood analyses result in virtually the same topology, and converge on the monophyly of Piperaceae and Saururaceae. Lactoris gains high support as sister to Aristolochiaceae subf. Aristolochioideae, but the different tree inference methods yield conflicting results with respect to the relationships of subfam. Asaroideae. In Piperaceae, a clade formed by the monotypic genus Zippelia and the small genus Manekia (=Sarcorhachis) is sister to the two large genera Piper and Peperomia.  相似文献   

19.
Mature wood of Lactoris, not previously available for study, reveals ten distinctive characters: vessels with simple perforation plates; vessels in pore multiples; vessel-to-axial parenchyma pits scalariform or transitional, vessel-to-vessel pits alternate; fiber-tracheids with vestigial pits; fiber-tracheids, vessels, and axial parenchyma storied; axial parenchyma vasicentric scanty; axial parenchyma either not subdivided or, if subdivided, with thin nonlignified walls between the cells (like the septa in septate fibers); rays wide and tall, little altered during ontogeny; ray cells upright; and ray cells taller adjacent to fascicular areas. All of these features occur in woods of Piper and other Piperaceae. The systematic position of Lactoris is therefore reassessed. Evidence available to date is consonant with placement of Lactoridaceae in Piperales, in which it would be more primitive than Piperaceae or Saururaceae. Features cited as evidence for alternative placements of Lactoridaceae are reviewed.  相似文献   

20.
浙江珍稀濒危保护植物的地理分布及其区系特征   总被引:13,自引:0,他引:13  
本文分析了浙江珍稀濒危保护植物56种的地理分布和51属的分布区类型及其区系特征,其结果如下: 1.本区存在较多的我国特有属,单型属、少型属的事实,说明浙江省的珍稀濒危植物区系的古老性和相对原始性。2.根据51属的分布区类型的分析,其属具有明显的温带性质,而56种的地理分布则以亚热带区系成分为主,它们与华中亚热带区系植物关系密切。  相似文献   

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