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1.
通过扫描电镜对澜沧荛花Wikstroemia delavayi花部的形态发生过程进行了观察和分析,旨在为该属的系统学研究提供花部发育形态学资料。澜沧尧花花部的发生和早期发育呈远轴面向近轴面的顺序,但这一式样由于近轴面的器官在早期发育之后生长加速发生了转变。因此,花开放时所表现的所谓辐射对称,显然是由同一轮器官的异率生长所导致的次生现象。花盘发生于花萼筒基部的远轴面上,与花萼、雄蕊的发生间隔时间较长。花盘原基在下轮雄蕊着生处凹陷或间断,与之相对应,花盘裂片与下轮雄蕊呈互生。由此,花盘显然不是花托的一部分,也不是象花萼、雄蕊和心皮一样的独立结构,将其解释为雄蕊群的一部分更合理。花盘的发生和早期发育及其着生位置同其他花部器官的发生和发育式样具有明显的相关性,这种相关性对进一步阐明瑞香属Daphne和荛花属Wikstroemia的系统发育关系具有—定意义。根据对雌蕊群的发生和发育过程观察,该种的子房是由一个近轴面的可育心皮和一个远轴面的不育心皮融合而成的单室子房,为假单心皮雌蕊。尽管荛花属和瑞香属均属于单室产房,但澜沧荛花的子房维管束中的腹束排列于中轴位置,而目前资料显示瑞香属植物的腹束接近于侧膜位置,这方面仍需进一步研究。  相似文献   

2.
通过扫描电镜对澜沧荛花Wikstroemia delavayi花部的形态发生过程进行了观察和分析,旨在为该属的系统学研究提供花部发育形态学资料.澜沧荛花花部的发生和早期发育呈远轴面向近轴面的顺序,但这一式样由于近轴面的器官在早期发育之后生长加速发生了转变.因此,花开放时所表现的所谓辐射对称,显然是由同一轮器官的异率生长所导致的次生现象.花盘发生于花萼筒基部的远轴面上,与花萼、雄蕊的发生间隔时间较长.花盘原基在下轮雄蕊着生处凹陷或间断,与之相对应,花盘裂片与下轮雄蕊呈互生.由此,花盘显然不是花托的一部分,也不是象花萼、雄蕊和心皮一样的独立结构,将其解释为雄蕊群的一部分更合理.花盘的发生和早期发育及其着生位置同其他花部器官的发生和发育式样具有明显的相关性,这种相关性对进一步阐明瑞香属Daphne和荛花属Wikstroemia的系统发育关系具有一定意义.根据对雌蕊群的发生和发育过程观察,该种的子房是由一个近轴面的可育心皮和一个远轴面的不育心皮融合而成的单室子房,为假单心皮雌蕊.尽管荛花属和瑞香属均属于单室子房,但澜沧荛花的子房维管束中的腹束排列于中轴位置,而目前资料显示瑞香属植物的腹束接近于侧膜位置,这方面仍需进一步研究.  相似文献   

3.
详细描述了广西荛花属一个新变种——黄药白花荛花Wikstroemia trichotoma (Thunb.) Makino var. flavianthera S. Y. Liu。本变种与原变种不同在于侧脉较多,达11对,萼筒非肉质,花药黄色,子房棒状,无毛。  相似文献   

4.
确认了中国瑞香科Thymelaeaceae存疑植物柳叶荛花Wikstroemia salicina(Levl.)Levl.&Blin为中国植物记录,同时补充描写了一些其重要的分类学特征。  相似文献   

5.
峨眉尖舌苣苔(苦苣苔科)花部形态发生及其系统学意义   总被引:3,自引:0,他引:3  
观察了峨眉尖舌苣苔(Rhynchoglossumomeiese)花序及花的形态过程,并同近缘类群进行比较和分析,结论如下:1)峨眉大苣台花发生组织通常的总状花序分生组织已发生开变和位偏从而导致不平衡分化,形成花偏向于腹部一侧的变了形的总状花序,2)花冠和能育雄蕊的两侧性可能和退化雄蕊相关。3)该种雄蕊早期的发生和发育过程仍保持着祖先群群中轴肥座的系统发生式样,并在随后的发育过程中转变成侧膜胎座,4  相似文献   

6.
由于四福花Tetradoxa顶花、侧花均为典型的4数花,并被认为是科内最原始的属,因而长期以来关于五福花Adoxa“总苞一萼”还是“萼一花冠”的争议得到了彻底解决。根据本研究,五福花顶花和侧花的变异痃较五福花科另外3个分类群要高得多。五福花顶花和侧花的变异率分别为20%和361%。通过后位雄蕊的退化和两则相邻花瓣的融合,雄蕊和花瓣从6数至3数的减少系列仅存在于五福花中。本文假设五福花科顶花和侧花的  相似文献   

7.
利用扫描电镜(SEM)观察了吉祥草(Reineckia carnea)(铃兰科)的花部器官发生发育过程。吉祥草花被片、雄蕊的发生方式是由近轴端向远轴端发生的逆单向型(reversed unidirection),花发育后期花被片合生形成花被筒,花丝与之贴生。伴随花被片、雄蕊发生,三枚心皮也由近轴向远轴方向相继发生,随后彼此合生发育。花序顶部的花易发生花器官数目变异。结合早期花原基形态以及花器官数目变异情况分析,吉祥草的花被片与雄蕊可能是由共同原基分化而成。从花部器官发生式样和花被筒形成时间两方面比较吉祥草属、白穗花属和铃兰属的特征发现,三属中,铃兰属处于相对进化的位置,而白穗花属比吉祥草属更为原始。  相似文献   

8.
南天竹属的花部器官发生及其系统学意义   总被引:1,自引:1,他引:1  
报道了南天竹(NandinadomesticaThunb.)(小檗科)的花部器官发生。发现该属植物萼片、花瓣和雄蕊的发生式样为三数轮生;雄蕊与花瓣是经它们所具有的共同原基进行侧向分裂而形成的;花瓣发育早期存在迟滞发育的阶段;心皮发生属于瓶状发生类型。讨论了花器官的三基数性质,小檗科花瓣的来源,雄蕊对瓣着生及单心皮雌蕊的形成等问题。对本属的花部个体发育性状同小檗科中已有报道的红毛七属(Caulophylum)、足叶草属(Podophylum)进行了比较,萼片多数轮列与心皮发生的多态现象是南天竹属的独特性状。  相似文献   

9.
对中国杜鹃花科特有种:臭越橘(Vaccinium foetidissimum H. Lév. & Vaniot)的花部形态特征进行了描述。基于新补充的花部特征,讨论了该种与其相似种的区别。  相似文献   

10.
掌叶木的花器官发生及其系统学意义   总被引:7,自引:0,他引:7  
利用扫描电子显微镜和光学显微镜观察了掌叶木的花器官发生过程。观察结果表明: 花序原基最先发生, 然后形成两个大小不一的花原基; 萼片原基的发生不同步, 螺旋状向心发生; 4-5枚花瓣原基以接近轮状方式近同时发生; 不存在花瓣-雄蕊复合原基; 7-8枚雄蕊原基为近同时发生, 其生长较花瓣原基快; 心皮原基最后发生, 3枚心皮原基为同时发生。花为单性花。在雌花中, 子房膨大而雄蕊退化。在雄花中, 雄蕊正常发育, 子房退化。讨论了掌叶木花器官发生和发育的系统学意义。  相似文献   

11.
Floral morphogenesis of Wikstroemia delavayi Lecomte was investigated by scanning electron microscope (SEM) and compared with its allied groups. Initiation and early development of floral parts in W. delavayi followed unidirectional sequences from the abaxial side to the adaxial side. Because the floral parts grew faster at the adaxial side than at the abaxial one in following development, the zygomorphic pattern in the early development changed and finally became an almost actinomorphic form at anthesis. The disc was initiated from the abaxial base of the floral tube and itslobes were alternate with lower whorl stamens. According to this initiatial and developmental pattern, it is reasonable to interpret the disc as a part of the androecium rather than a modification of the receptacle. The located position and development of the disc was correlative with the development of other floral organs, which might provide insight to delimit Wikstroemia and Daphne based on different floral developmental pattern that might exist between the two genera. The developmental process of W. delavayi indicated that the syncarpous and uniloculate gynoecium was in fact bicarpellate, which consisted of a fertile carpel and a sterile one. It was pseudomonomerous. Even though the ovary in both Wikstroemia and Daphne was uniloculate, the location of the ventral bundles in the ovary was obviously different from each other according to data to date. In this respect, further investigation is undertaken between the two genera.  相似文献   

12.
Fifty six species (varieties) of Daphne, forty five species (varieties) of Wikstroemia and twelve species of outgroups from Thymelaeaceae, with ten phenotypic characters were selected, to study the leaf epidermal microfeatures by using light microscopy, Results reveal that Daphne and Wikstromia are consistent in most of leaf features. The epidermal cell are polygonal and irregular in shape. The patterns of anticlinal wall are straight, curved and U shape. The cell sizes range in 30-40μm × 10-20μm. Some species have singly hair on surface. Stomatal distribution is random, size range in 20-36μm × 17-25μm, most are broadly elliptical and narrowly elliptical, stomatal frequency are 100-250S/mm2, and the anomocytic stomatal type is dominate. It is apparently that many stomatal and epidermal features in Daphne and Wikstromia are crossed, and no distinguishable features are suitable for separating this two genera. Results from epidermal characters analysis don’t support monophyletic status of Daphne and Wikstroemia. Eriosolena should not be include in the genus Daphne as the special papillae only found in Eriosolena composita rather than in other genera of Thymeleaceae. In compare with other genera, Rhamnoneuron, Eriosolena, Stelleropsis, Daphnopsis and Edgeworthia in Thymelaeoideae, Daphne and Wikstroemia might be derived and originated latter based on the stomatal features.  相似文献   

13.
14.
Floral morphology in all ten species ofCrossostylis, one of the inland genera of Rhizophoraceae and is distributed in the South Pacific Islands, was studied to increase our knowledge on floral features of individual species as well as on relationships among the species. Flowers ofCrossostylis, unlike those of the other Rhizophoraceae, always have semi-inferior ovaries and entire petals, but are diversified concerning the number and arrangement of stamens and carpels, the presence or absence of staminodia, sexuality and the structure of nectaries. Despite some doubt of the presence of apomorphies restricted to the whole genus, we tentatively definedCrossostylis by a combination of the presence of the semi-inferior ovary, entire petals, and arillate seeds, and then performed cladistic analysis on the basis of 24 floral and other morphological characters and withCarallia andGynotroches as outgroups. Our phylogenetic analysis suggested that the species ofCrossostylis are divided into two monophyletic groups: one comprising six species distributed in the Solomon Islands, Vanuatu and the Fiji Islands, and the other comprising four species distributed in New Caledonia and Polynesia.  相似文献   

15.
利用扫描电镜观察了驴蹄草Caltha palustris L.和川陕金莲花Trollius buddae Schipcz.花器官的发生和发育过程。结果显示:驴蹄草和川陕金莲花的所有花器官均螺旋状向心式发生、向心式发育,花器官的螺旋状发生方式在毛茛科Ranunculaceae可能是一种基本式样;苞片、萼片与其他花器官原基的形状明显不同,显示苞片、萼片与其他花器官在系统发生上有所不同;川陕金莲花的花瓣在早期延迟发育且基部具囊,花瓣的延迟发育在毛茛科具花瓣的属中非常普遍,而花瓣基部的囊类似于耧斗菜属Aquilegia一些植物;两个属雄蕊群一纵列雄蕊中的小孢子均向心式发育,这种发育方式在毛茛科可能为基本类型。两个属植物的心皮原基均为对折式,在发育过程中,驴蹄草心皮顶端沿腹缝线形成下延的柱头组织,川陕金莲花不形成明显的柱头组织。根据花形态发生和发育特点,并结合其他研究成果,认为这两个属不应当属于同一个族。  相似文献   

16.
Floral development was investigated in Ruta graveolens and Psilopeganum sinense, representing two genera in the tribe Ruteae. Special attention was paid to the sequence of initiation of organ whorls in the androecium and gynoecium. The antepetalous stamens arise at the same level as the antesepalous stamens in both species. The carpels are antepetalous in both taxa, indicating the androecium in both genera is obdiplostemonous. Compared with floral ontogeny of the ancestral genus Phellodendron (Toddalioideae), the obdiplostemonous androecium is a derived condition. The floral apex in P. sinense is quadrangular before initiation of the two carpels. Additionally, there are four dorsal and four ventral traces in the ovary. Integrated morphological and anatomical evidence indicates that the bicarpellate gynoecium in Psilopeganum most likely evolved from a tetracarpellate ancestor. Considering the similarities in morphological, geographical and chromosomal features, the ancestor may be Ruta‐like. Further molecular phylogenetic and genetic studies are needed to verify this assumption.  相似文献   

17.
18.
罗敏蓉 《广西植物》2020,40(11):1645-1652
花的发生和发育过程研究可以发现早期进化的轨迹,为系统发育的研究提供重要线索。蓝堇草属(Leptopyrum)为毛茛科唐松草亚科一单种属,仅包含蓝堇草一种,其花的发生和发育过程仍为空白。为了深入理解唐松草亚科乃至毛茛科花发育多样性和演化规律,该文运用扫描电子显微镜(SEM)观察了蓝堇草各轮花器官的形态发生和发育过程。结果表明:该属植物所有的萼片、花瓣、雄蕊和雌蕊均为螺旋状发生,花器官排列式样也为螺旋状; 5枚萼片原基宽阔,5枚花瓣原基圆球形、位于萼片原基的间隔,且在后期表现为延迟发育现象,雄蕊原基较小、为圆球形;花瓣原基和雄蕊原基连续发生,无明显的时空间隔,但与萼片原基有时空间隔;心皮原基为马蹄形对折,柱头组织由单细胞乳突组成;胚珠倒生、具单珠被。该属花器官螺旋状排列、胚珠具单珠被在唐松草亚科中是独有的性状,花发育形态学证据支持了该属的特殊性。  相似文献   

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