论文标题:类叶升麻（毛茛科）形态结构、发育及系统位置的研究
Morphology, Structure, Development and Systematics of Actaea Asiatica Hara. (Ranunculaceae)
论文作者
论文导师 任毅,论文学位 硕士,论文专业 植物学
论文单位 陕西师范大学,点击次数 154,论文页数 75页File Size14136K
2006-05-01论文网 http://www.lw23.com/lunwen_116866612/
Actaea asiatica;anatomy;floral organogenesis;embryology;systematic position
类叶升麻(Actaea asiatica)为东亚特有种,隶属于毛茛科(Ranunculaceae)升麻族(Trib.cimicifugeae)类叶升麻属(Actaea Linn.)。本文从形态结构、木质部管状分子、花器官发生发育、胚胎学等方面对类叶升麻进行了研究,对于确定其系统位置提供详细的资料。结果如下: 1.形态结构 类叶升麻根尖由根冠和顶端分生组织构成;根的初生结构由表皮、皮层和维管束组成,为二原型和四原型维管束;无次生根结构。 茎的初生结构和次生结构相似,由表皮、皮层和维管束组成。根、茎维管束木质部排列为典型的“V”字型。 茎节部为单隙多迹。 叶柄马蹄型,维管束排列呈环状;叶下表皮细胞为不规则型,具不规则型气孔器;叶上表皮具条纹加厚的瘠。 在花托上着生花被片、雄蕊群和雌蕊。萼片迹为单隙2迹,花瓣和雄蕊迹为单隙单迹,心皮基部具3迹。心皮、花瓣表皮具气孔器。 2.木质部管状分子 根和根状茎中次生木质部的管状分子类型丰富,主要有:管胞、管胞状导管、纤维导管和典型的导管分子;在导管分子中,存在着梯状穿孔板、网状穿孔板、混合型穿孔板和单穿孔板;导管分子上的侧壁穿孔板、多穿孔板和纹孔膜残余有不同的类型;管状分子在类叶升麻不同器官的分布也不同。 3.花器官的发生发育 类叶升麻花部器官轮列;花部各器官的发生方式为向心式;萼片、花瓣、雄蕊为螺旋状发生。花瓣与雄蕊同源,且花瓣具有延迟发育现象;早期心皮腹部产生凹陷,接着经过椅形阶段形成成熟心皮。心皮无明显花柱;柱头具乳突状细胞。 4.胚胎学研究 类叶升麻花药四室,花药壁由表皮(1层细胞)、药室内壁(2—3层细胞)、中层(1层细胞)和绒毡层(1层细胞)组成。其绒毡层为腺质绒毡层。花药壁的形成为基本类型。小孢子母细胞分裂为同时型:小孢子四分体为四面体型,偶尔可见交叉型;花粉散播时为两核花粉,花粉三沟型。 胚珠倒生,双珠被,厚珠心,功能大孢子位于合点端,胚囊发育为蓼型,核
The anatomical structure, trancheary elements, flora morphogenesis and embryology of Actaea asiatica which is an endemic and monotypic genus of Ranunculaceae in East Asian were described in the present paper. We attempted to supply some new features on the determination of the systematic position of Actaea in Ranunculaceae.1. Anatomical Structures of ActaeaRoot: root tip is consisted of initial cells of calyptrogen,periblem and plerome;the root with diarched and tetrarched primary xylem;without secondary structure in root.Stem: The secondary structure in stem is similary to the primary structure in stem, and the vascular arranged in tapical "V".Node:the node is unilacunar and multi-traced.Leaf: The stomata of leaves are anomocytic type.The vascular bundles of the petiole are arranged in circle.The inferior epdermis cells are anomalistic.Ridge distributing on the upper epidermis cells of leaf.Flower: There are perianth,androecium and gynoecia on receptacle.The node of sepals is unilacunar and 2-traced,while the nods of petals and stamens are unilacunar and 1-traced.There is 1 carpel that is 3 traces in the basal.The configurations and vascular of stamens and petals are similar.2. The treachery elements in the xylem of Actaea asiaticaThe types of trancheary elements in the root and rhizome of the genera are varied.The major types include:Tracheary, tracheid-like vessels,fibriform vessels and typical vessels.The form of the perforation plates in the typical vessels are various,divide into several subtypes:scalariform perforation plates,reticulate perforation plates.mixed perforation plates and simple perforation plates.Lateral-wall perforation plates,multiple end wall and the membrane remnants are also observed in the secondary xylem.The distribution of the vessels in different organs of Actaea is difference.3. Floral morphogenesisThe initiation of floral organs is centripetal;the petals and the stamens are spiral ininitiation while are whorled in later development stage;the primordials of stamens and petals are homeosis,the petals are retarded;the carpel conduplicated at the early stage and from chair-shape to the mature stage. The stigma with inconspicuous style and papillary cells at the top of the carpel.4. EmbryologyThe features of the microspores and the male gametophyte of Actaea asiatica are: the young anther is tetralocular;the mature anther wall comprises the epidermis,the endothecium,2-3 middle layers and a glandular tapetum;microspore is simultaneous type;pollen tetrads are tetrahedral and cross type.Two-cells at the shedding stage of the pollen;The ovule of Actaea is anatropous,bitegmic and crassinucellate ovule;the chalazal functional megaspore developed into a polygonum type of embryo sac;the endosperm development of Actaea was the nuclear type.5. Systematic positionAccording to the characters of anatomy,treacheary elements,floral organogenesis and embryology of Actaea.We considered that Actaea should be an espiceally group in Trib Cimicifaga.
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