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排序方式: 共有37条查询结果,搜索用时 15 毫秒
1.
在电子扫描显微镜下观察了穆属(Eleusine Gaertn.)9种植物颖果的微形态特征.结果表明,穆属颖果有卵形、披针形和矩圆形3种腹面形状,压扁方式有背腹压扁及两侧压扁,腹面形态有平腹面和凹腹面两种,胚比为0.29~0.58,种脐比为0.10~0.24,颖果纹饰有2种,包括疣突状一级纹饰和疣突规则排列构成的复合网状...  相似文献   
2.
东方大黄蜂(胡蜂)Vespa orientalis(膜翅目Vespinae属)的胃部表皮黄色颗粒位于黄色条纹区域。从黄色颗粒产生至在这一区域扩散,这个过程就是胃部黄颜色形成的过程。用几种电子显微镜研究了黄色颗粒的微观形态和发育过程。结果显示黄色颗粒由20—25 µm厚的一层组成,包括总表皮在内厚度约为40—45 µm。从上面看,在上述的区域能看到许多直径大约为0.5 µm周边光感受器细胞(PPC)。在每个黄色颗粒,能观察到一个肌样包膜,它位于一个由9根原纤维组装而成的圆圈内部。黄色颗粒成熟的过程包含通过导管的渗透增加初生黄色粒子数量,这些初生粒子又发育或增生成次生粒子,次生粒子逐渐布满整个区域。在这些黄色粒子层内可产生类似于肝的功能活动。  相似文献   
3.
中国荞麦属果实形态特征   总被引:7,自引:0,他引:7  
应用解剖镜和扫描电镜对中国产荞麦属Fagopyrum Mill.8种1变种的果实形态和微形态特征进行了观察。结果表明这些种类的果实可分为3类:(1)果实三棱锥状,表面不光滑,无光泽,具皱纹网状纹饰,此种类型的植物有苦荞麦、金荞麦。(2)果实卵圆三棱锥状,表面光滑,有光泽,具条纹纹饰,此种类型的植物有荞麦、长柄野荞麦、线叶野荞麦。(3)果实卵圆三棱锥状,表面光滑,有光泽,具大量的瘤状颗粒和少数模糊的细条纹纹饰,此种类型的植物有硬枝野荞麦、细柄野荞麦、小野荞麦、疏穗小野荞麦。研究结果认为金荞麦与栽培种苦荞麦关系较近。  相似文献   
4.
The fine structure of the cell envelope, of membrane systems and of cytoplasmic inclusions of Gram-negative aerobic hydrogen bacteria has been studied. The results have been tabulated, and three main groups could be recognized: Group 1: Alcaligenes eutrophus, A. paradoxus, A. ruhlandii, Pseudomonas facilis, P. flava, P. pseudoflava, P. palleronii, and Aquaspirillum autotrophicum; Group 2: Corynebacterium autotrophicum and strains MA 2 and SA 35; Group 3: Paracoccus denitrificans. Special structures related to the chemoautotrophic way of life of the hydrogen bacteria were not observed.Abbreviations CM cytoplasmic membrane - OM outer membrane  相似文献   
5.
利用光学显微镜和环境扫描电子显微镜,对不同颜色、不同产地玛咖(Lepidium meyenii)的叶表皮、花粉粒以及种皮进行了微形态学研究。结果表明:(1)不同颜色玛珈的叶表皮、花粉粒微形态具有高度的一致性,但与我国部分独行菜属植物有着明显的差异;(2)不同产地、不同颜色玛珈的种皮微形态有明显的差异。该研究为新植物资源玛咖的种质鉴定、分类提供了一些新的依据。  相似文献   
6.
Abstract

A study on the type and distribution of trichomes, morphological traits of the calyx and content of antioxidant compounds was conducted on Teucrium arduini L. populations in Croatia and in Bosnia and Herzegovina. Non-glandular trichomes, peltate trichomes and small capitate trichomes with four secretory head cells were observed on leaves, stems and calyx, whereas long capitate trichomes with a unicellular head cell were observed exclusively on the calyx. Average calyx length was 5.23–6.51 mm, calyx tube length 2.92–3.68 mm, lower lip length 1.25–2.42 mm and upper lip length 1.89–2.99 mm. The concentration of antioxidant compounds in all populations was the highest in leaves: total polyphenols (TP): 8.43–13.55%; tannins (T): 1.79–7.33%; flavonoids (TF): 0.28–0.40%; phenolic acids (TPA): 2.90–5.07%. Inflorescences generally contained the smallest amount of TP (5.89–11.42%), T (0.87–6.50%) and TPA (1.66–2.27%), while the smallest content of TF was obtained for the majority of stem samples (0.06–0.12%). The researched populations did not differ with regard to the type and overall distribution of the trichomes, though the Bosnian populations have a shorter calyx tube and longer upper lip. Some variability was observed in the TP and T content between sampling sites, while quite high variability was noted in the TF and TPA content.  相似文献   
7.

The new species Nonea pisidica (Boraginaceae-Boragineae) is described based on two collections by the authors from the region of Lake Burdur in southwest Anatolia, Turkey. It shows a combination of morphological characteristics concerning habit, flower, and fruit that distinguishes it from N. caspica and N. pallens, the two more similar taxa in Nonea sect. Nonea. Karyological analyses corroborate the separation of the three species, which have different chromosome complements and even base numbers. N. pisidica is characterised by 2n = 30, a complement previously unknown for west Asiatic species of Nonea. The dibasic haploid number x = 15 may have originated through amphidiploid hybridisation between two annual, diploid taxa with x = 7 and x = 8, such as N. lutea and N. caspica. The relationships of the new species were further analysed using trnLUAA sequences of the chloroplast genome, which were obtained for 16 selected species of Nonea. The resulting phylogeny confirms that it is related to N. caspica and N. lutea, but not to N. pallens, in spite of morphological resemblance. Lack of relationship with the south Mediterranean N. vesicaria, the only other species of Nonea known to have 2n = 30, suggests that amphidiploidy may have played an important role in speciation processes through recurrent and polytopical occurrence.  相似文献   
8.
山茶属花粉外壁表面微形态特征的研究   总被引:6,自引:0,他引:6  
在前人研究的基础上,利用光学显微镜和扫描电镜观察了山茶属17个组34个代表种(含变种)的花粉形态;按照韦仲新划分山茶属花粉类型的标准,对其进行归类,所有花粉分为3类:颗粒状至皱颗粒状纹饰、皱沟状纹饰和穴-网状纹饰;发现1种新的花粉类型:拟穴-网状纹饰。本文还对山茶属的某些分类学问题作了初步探讨。  相似文献   
9.
东方大黄蜂(胡蜂)Vespa orientalis(膜翅目 Vespinae属)的胃部表皮黄色颗粒位于黄色条纹区域.从黄色颗粒产生至在这一区域扩散,这个过程就是胃部黄颜色形成的过程.用几种电子显微镜研究了黄色颗粒的微观形态和发育过程.结果显示黄色颗粒由20-25pm厚的一层组成,包括总表皮在内厚度约为40-45μm.从上面看,在上述的区域能看到许多直径大约为0.5μm周边光感受器细胞(PPC).在每个黄色颗粒,能观察到一个肌样包膜,它位于一个由9根原纤维组装而成的圆圈内部.黄色颗粒成熟的过程包含通过导管的渗透增加初生黄色粒子数量,这些初生粒子又发育或增生成次生粒子,次生粒子逐渐布满整个区域.在这些黄色粒子层内可产生类似于肝的功能活动.  相似文献   
10.
Trichomes of 37 taxa of the genus Stachys and one species of Sideritis (S. montana) were examined using light and scanning electron microscopy. The indumentum shows considerable variability among different species, but is constant among different populations of one species, and therefore, affords valuable characters in delimitation of sections and species. The characters of taxonomic interest were presence of glandular and non-glandular trichomes, thickness of the cell walls, number of cells (unicellular or multi-cellular), presence of branched (dendroid) trichomes, presence of vermiform trichomes, orientation of trichomes in relation to the epidermal surface, curviness of trichomes, and presence of papillae on trichome surface. Two basic types of trichomes can be distinguished: glandular and non-glandular trichomes. The glandular trichomes can in turn be subdivided into subtypes: stalked, subsessile, or sessile. The stalks of the glandular trichomes can be uni- or multi-cellular. Simple unbranched and branched trichomes constitute two subtypes of non-glandular trichomes. Our data do not provide any support for separation of Sideritis from Stachys. The following evolutionary trends are suggested here for Stachys: vermiform trichomes with stellate base are primitive against vermiform trichomes with tuberculate base, long vermiform trichomes are primitive against the short simple trichomes, appressed trichomes are advanced against spreading ones, and loss of glandular trichomes is advanced against their presence. Overall, trichome micromorphology is more useful in separation of species within sections rather than characterizing large natural groups known as sections, except for few cases.  相似文献   
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