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1.
This paper deals mainly with comparative studies on elements of secondary xylem in 39 species of Chinese Magnolia and Michelia. The former plants present longer and slender vessels. Most of them have simple perforation and only a few scalariform perforation plates. In contrast, most of the Michelia species possess scalariform perforation plates and only one with simple perforation. The scalariform perforation plates of Magnolia species, if present, exhibit more bars than that of Michelia With few exceptions, there is no spiral thickening on the vessel wall in Magnolia, whereas in Michelia it is lust the opposite. In addition, some other differences in vessel elements between these two genera are also discussed.  相似文献   

2.
This paper deals mainly with comparative studies on vessel elements of secondary xylem in Chinese Manglietia, Manglietiastrum, Alcimandra, Parakmeria, Paramichelia, Tsoongiodendron, Aromadendron and Liriodendron. There are some differences between the genera in vessel element length and width. Manglietia species all have scalariform perforation plates, only a few also have simple perforations. The other genera have scalariform perforation plates. only one (Tsoongiodendron odorum Chun) has simple perforations in addition. There are no spiral thickenings in Manglietia except for one species [Manglietia chingii Dandy (M. temuipes Dandy)] . Paramichelia and Liriodendron have no spiral thichenings, but they are present in the other genera. In addition, some other differences in vessel elements between these 8 genera are also discussed.  相似文献   

3.
This paper deals with comparative studies of the root structure in 65 species of 36 genera of Ranunculaceae. Five types of the root structure were recognized in these species. A. The roots, in which the primary xylem was surrounded by the tracheary elements of the secondary xylem and the ray was absent, were always diarchy, as seen in Coptis. B. The rays were narrow and the tracheary elements of the secondary xylem were semicircle in shape, and the roots were diarchy, as seen in Leptopyrum. C. The rays and tracheary elements of the secondary xylem were sector in shape, and the roots were di-, tri-, and tetrarchy, as seen in Cimicifuga, etc. D. There was a few secondary xylem in the roots. D1. Primary structure was diarchy, in Kingdonia. D2. The roots were di-, tri-, tetra- and pentarchy, in Ranunculus etc. E. The secondary structure was absent. El. The roots were diarchy, in Asteropyrum. E2. They were di-, tri-, tetra- and pentarch, as seen in Caltha. According to comparative anatomical studies on the characteristics of the vessel elements and other parts of plant (carpel, petiole and vena- tion), the roots which were always diarcby whether in older or young, and whether the tra- .cheary elements of the secondary xylem well orless developed, could be considered as the most primitive type, for example: type A (Coptis) and type El (Asteropyrum). It would be con- cluded that the evolution of the root structure from primitive to specialized type was in the order from type A→B→C→D2→E2 and E1→D1 in Ranunculaceae.  相似文献   

4.
对蜈蚣草(Pteris vittata)叶轴中导管分子进行了观察。结果表明,其导管分子十分细长,均具长、且十分倾斜的梯状穿孔板,穿孔没有纹孔膜的残余,与侧壁上的梯纹纹孔有着明显的差异。  相似文献   

5.
利用扫描电子显微镜对东亚特有植物黄三七( Souliea vaginata (Maxim. ) Franch. ) 茎的次生木质部
离析材料进行了观察, 结果表明, 黄三七茎次生木质部中的导管分子端壁上具网状穿孔板( 麻黄式穿孔
板) 、梯状穿孔板、网状- 梯状混合穿孔板、网状- 梯状- 单穿孔混合型穿孔板、梯状- 单穿孔混合型穿
孔板及单穿孔板, 同时也观察到了端壁多穿孔板和侧壁穿孔板, 并对不同类型穿孔板中纹孔膜的残留也进
行了观察。其中, 网状穿孔板、各种过渡类型的穿孔板均为毛茛科植物中首次报道。根据观察结果, 对导
管分子穿孔板的演化及黄三七属植物的系统位置进行了分析。  相似文献   

6.
Spiral thickenings in the inner walls of vessels were studied in 10 genera 69 species of Magnoliaceae in China under scanning electron microscopic observation. Spiral thickenings were found in some species. The majority of these species showed complete thickenings of the inner wall, however, in some of which the spiral thickenings were less obvious at both ends. In others, these spiral thickenings existed only in the middle portion, uniformly or irregularly distributed.  相似文献   

7.
罗敏蓉 《广西植物》2021,41(1):123-132
导管分子的演化与植物的进化相关联.毛茛科是联系基部被子植物和核心真双子叶植物的关键类群,对其导管穿孔板的研究具有重要的系统学意义.为研究毛茛科毛茛族不同属植物导管穿孔板类型及其与环境的相关性,该文利用新的扫描电子显微镜和半薄切片技术,对该族7属8种植物次生木质部导管状分子进行了比较观察.结果表明:木质部管状分子以单穿孔...  相似文献   

8.
对蜈蚣草(Pteris vittata)叶轴中导管分子进行了观察。结果表明,其导管分子十分细长,均具长、且十分倾斜的梯状穿孔板,穿孔没有纹孔膜的残余,与侧壁上的梯纹纹孔有着明显的差异。  相似文献   

9.
芒果次生木质部导管分子的观察   总被引:10,自引:1,他引:10  
运用细胞图象分析系统及显微照相的方法对芒果(Mangifera indicaL.)次生木质部不同的导管分子进行了观察。并且对这些导管分子的构造、进化趋势以及同一导管分子上的特殊结构进行了详细的讨论。  相似文献   

10.
台湾青枣导管分子及其穿孔板研究   总被引:1,自引:0,他引:1  
运用细胞图象分析系统及显微照相的方法对台湾青枣Z iziphus mauritiana次生木质部导管分子进行了观察研究。在台湾青枣的次生木质部导管分子中存在着许多不同的样式,并且导管分子穿孔板存在着3种类型:两端均为一个单穿孔板;一端为一个单穿孔板,另一端为梯状穿孔板;具纤毛的单穿孔板。分别对其进行了描述,并从导管分子个体发育与系统发育的角度进行了讨论,认为3种类型的穿孔板为导管分子穿孔板的系统演化提供了新的证据。  相似文献   

11.
标本室和野外观察表明匙苞翠雀花(Delphinium subspathulatum W. T. Wang)和吉隆翠雀花(D. tabatae Tamura)与须弥翠雀花(D. himalayae Munz)属于同一种植物,故将前二者均处理为须弥翠雀花的异名。  相似文献   

12.
This paper reports the result of comparative anatomical studies on medicinal roots of 53 species and varieties in the genus Aconitum from China. The anatomical structures of the roots can be classified into 6 types and 18 subtypes according to the level of their evolution. The anatomy of Aconitum roots is discussed in relation to phylogeny based on chemotaxonomy, cytology and other related disciplines. It was found that the six types of Aconitum roots are correlated with chemical components, chromosomes, toxicity and the gross morphology. The relatively advanced Types I and II roots always contain highly toxic alkaloids of diterpenoid diester of aconitine type, distributed mainly in Ser. 3, 5-11 of Sect. Aconitum of Subgen. Aconitum, while the relatively primitive Types III, IV and II roots with small diameters contain mainly atisine and aminal alcohol alkaloids, which have lower toxicity, present in Subgen. Gymnaconitum and Ser. 1, 2 of Sect. Aconitum of Subgen. Aconitum. The primitive Types V and VI roots of Subgen. Lycoctonum contain mainly the most low-toxic alkaloids of lycoctonine Type. The result is of significance both in theory or practice for the development of medicinal plant resourcesand the safety of clinical usage of these of plants.  相似文献   

13.
On the basis of biosynthsis, distribution of diterpenoid alkaloids as well as morphological evolution of Chinese species L. (Ranunculaceae), chemotaxonomy of the genus Aconitum is discussed: 1, Subgen. Lycoctonum, containing lycoctonine-type alkaloids and Subgen. Aconitum containing aconitine-type alkaloids, were probably differetiated at the early stage of evolution of the genus Aconitum and evolved respectively in their own ways. 2, In Subgen. Aconitum: (1) Ser. Bullatifolia, containing mainly atisine-, veatchine-type alkaloids, and amino, alcohol and ester base of aconitine-type, and distributed in Hengduan Mountain and Jingsha River valley, where is the centre of modern differentiation of species of Aconitum, is probably a series from which Chinese species of the genus Aconitum were derived; (2) Ser. Inflata, containing mainly aconitine, mesaconitine and bypaconitine, is an advanced group; (3) Ser. Grsndituberosa, containing mainly aconitine and songorine, is related to Ser. Bulatifolia; (4) Ser. stylosa and Ser. volubilia, containing mainly yunaconitine and other anisyl ester alkaloids form another advanced branch. 3, Ser. Tangutica and A. naviculare of Ser. Rotaundifolia, containing atisine and lactone-type alkaloids may be a specialized group in high mountains and have occurred at early stage of evolution of the genus Aconitum. 4, Subgen. Gymnaconitum, containing atisine-type alkaloids and amino alcohol of aconitine type, may als be a specialized group in high mountains. 5, A. franchetii Finet. et Gagnep. mainly containing ester bases of aconitine-typeand closed to A. chasmanthum Stapf, is best placed into Ser. Ambigua.  相似文献   

14.
缺硼可导致柑橘叶片变厚而脆、发生木栓化、"猴头果"等现象,其原因是植物组织内部起运输作用的维管组织受到损坏。导管是维管组织重要组成部分,本实验以‘纽荷尔’脐橙(Citrus sinensis Osbeck ‘Newhall’)和HB柚[Citrus maxima (Burm.) Merr.‘HB You’]叶片、HB柚果实中果皮为材料,利用离析方法将导管分离,观察缺硼导管分子形态的变化。结果表明:(1)缺硼使纽荷尔脐橙叶脉中的孔纹导管数量增多;(2)缺硼使HB柚叶片和果实中果皮的孔纹导管大量增生,梯纹导管和网纹导管数量减少;(3)正常导管圆润饱满,而缺硼导管变形干瘪,且有侧壁穿孔现象;(4)缺硼导管变得短而窄,细胞壁变薄,无尾率增加,使维管组织功能丧失。(5)缺硼维管束受损,运输效率降低,是发生叶脉木栓化和"猴头果"现象的源头。  相似文献   

15.
毛茛科分子系统发育研究进展   总被引:1,自引:0,他引:1  
刘慧杰  谢磊 《西北植物学报》2016,36(9):1916-1924
毛茛科(Ranunculaceae)在被子植物的系统演化中占有十分重要的地位,其系统位置和科下演化关系一直备受争议。近20多年的分子系统学研究表明,以往基于形态学的分类系统与分子系统学研究结果存在巨大差异。通过形态学性状界定的绝大多数亚科都没有得到分子系统学支持。此外,通过形态学确定的一些属如升麻属(Cimicifuga)、黄三七属(Souliea)、獐耳细辛属(Hepatica)、白头翁属(Pulsatilla)和水毛茛属(Batrachium)等,根据分子系统学研究均应予以归并。而分子系统学研究也确立了一些类群的属级地位,如露蕊乌头属(Gymnaconitum)等。以中国分布的毛茛科植物为例,通过以往分子系统学研究,共有10个属被归并,2个属新被确立。然而,毛茛科分子系统学研究对于科下许多类群之间的关系目前仍然没有得到很好的解决,如毛茛亚科和翠雀族等类群的系统发育关系仍需要进行深入研究后方能确定。该文对近年来国内外有关毛茛科的分子系统学研究进展进行了综述,并对该科尚存的一些问题和未来的研究方向进行了讨论。  相似文献   

16.
黄连属(毛茛科)花的形态发生   总被引:5,自引:0,他引:5  
本文运用扫锚电子显微镜(SEM)观察了黄连属(Coptis)植物花的形态发生和发育过程,结果表明,该属植物所有的花部器官均为螺旋状发生,雄蕊为向心式发育,花瓣原基有微弱的延迟发育,心皮原基为对折型(即马蹄形),子房为半封闭类型,子房柄是在发育过程中形成的。通过与其它具T.型染色体类群在花形态发生上的比较,认为黄连属表现出了某些原始的性状,这一结果与分子系统学研究认为黄连属为毛莨科的基部类群的结论一致。  相似文献   

17.
利用扫描电子显微镜对东亚特有植物黄三七(Souliea vaginata(Maxim.) Franch.)茎的次生木质部离析材料进行了观察,结果表明,黄三七茎次生木质部中的导管分子端壁上具网状穿孔板(麻黄式穿孔板)、梯状穿孔板、网状-梯状混合穿孔板、网状-梯状-单穿孔混合型穿孔板、梯状-单穿孔混合型穿孔板及单穿孔板,同时也观察到了端壁多穿孔板和侧壁穿孔板,并对不同类型穿孔板中纹孔膜的残留也进行了观察。其中,网状穿孔板、各种过渡类型的穿孔板均为毛茛科植物中首次报道。根据观察结果,对导管分子穿孔板的演化及黄三七属植物的系统位置进行了分析。  相似文献   

18.
利用扫描电子显微镜对鹅掌楸属仅存的2个自然种鹅掌楸和北美鹅掌楸的次生木质部导管穿孔板特征进行了详细的研究。结果显示,鹅掌楸属的2个种均以梯状穿孔板为主,同时存在网状-梯状混合穿孔板。鹅掌楸和北美鹅掌楸的导管穿孔板具有明显差异:(1)鹅掌楸具网状穿孔板,而北美鹅掌楸没有观察到;(2)北美鹅掌楸具单穿孔板,而鹅掌楸在该实验中未发现;(3)北美鹅掌楸具有横隔较粗的梯状穿孔板且横隔数目较多;(4)鹅掌楸的导管穿孔板多数横隔较少;(5)北美鹅掌楸的穿孔板倾斜角度较大;(6)北美鹅掌楸具麻黄式穿孔板的存在,且有纹孔膜残留存在。研究认为,北美鹅掌楸导管分子穿孔板分化较鹅掌楸更为剧烈。  相似文献   

19.
木犀属植物叶柄的比较解剖学研究   总被引:1,自引:0,他引:1  
对木犀属(Osmanthus)26种植物叶柄的解剖结构进行了研究.结果表明,木犀属植物叶柄的解剖特征存在比较丰富的变异,叶柄横切面形状有3种类型(U型、V型、Y型),周缘波状、浅波状或近平滑;表皮毛有或无;维管束一般为1大2小,维管束轮廓在种问变异丰富,维管束类型有周韧、近周韧、外韧3种;小叶月桂、牛矢果、厚边木犀、美洲木犀叶柄中央具髓腔,部分种叶柄有硬化细胞或石细胞存在.木犀属植物叶柄的解剖结构特征比较稳定,可作为该属的分种特征.  相似文献   

20.
本文描述了 8种国产毛茛科植物的地理分布新资料 ,并且在分类学上将铁线莲属锈花铁线莲毛变种归并入原变种。  相似文献   

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