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Seeds and trichomes of 15 taxa of the genus Glaucium distributed in Iran were examined by light microscopy (LM) and scanning electron microscopy (SEM). The seeds are slightly shiny to rather shiny, however, strongly shiny seeds were also observed in some species (G. corniculatum and G. grandiflorum). The basic shape of the seeds is semicircular to reniform, but reniform and elongated reniform seeds were found in G. oxylobum and G. elegans, respectively. The sculpturing of the testa surface are verrucate–rugulate (most frequent type), verrucate–granulate, verrucate–perforate, verrucate–lineolate, rugulate–granulate, rugulate and ocellate. Elongated polygonal epidermal cells dominate in most taxa investigated, but there are polygonal and irregular polygonal cells in a few taxa. The investigated species have two types of trichomes on the ovary: tuberculate and non‐tuberculate. The non‐tuberculate trichomes are of two subtypes: pilose and squamiform. Based on the number of cells, the squamiform trichomes were further divided into two groups (uniseriate and multiseriate) differing in shape, size and cellular structure. The results show that the micro‐morphological characteristics of seed and ovary trichomes provide useful and significant information for separation of species and taxa within species and a diagnostic key to the taxa is provided.  相似文献   

3.
Morphological features of nutlets of all members of the genus Limnanthes were examined by light and scanning electron microscopy (SEM). Eight distinct nutlet types are recognized on the basis of presence or absence, size, shape, density, and color of tubercles and associated filamentous or globular background structures. Some taxa (e.g., L. macounii, L. bakeri) display only one nutlet type, some (e.g., L. floccosa floccosa) have different types in different populations, and others (e.g., L. alba, L. striata) have two or more types within populations. Four classes of nutlets are designated as subtypes on the basis of their forms varying between the eight types recognized. The relationships among various taxa on the basis of nutlet types are schematically diagrammed and compared with other classification schemes. Results suggest that the proposed details of nutlet morphology should be considered in an identification key. Preliminary evidence indicates that certain highly sculptured (tuberculate) nutlet types with large surface areas occur more often in wetter habitats and that variation in this trait in different Limnanthes species might be adaptively associated with geographical distribution patterns.  相似文献   

4.
Seed and fruit morphology of four genera of Orobanchaceae: Cistanche, Diphelypaea, Orobanche and Phelipanche, native to Turkey, were studied using light and scanning electron microscopy. In this study, 100 accessions belonging to 39 species were investigated. The examined fruits had loculicidal capsules, generally dehiscing with 2 slits, and the seeds were small and with reticulate ornamentation. The basic shape of the seeds in most of the studied taxa was oblong, ellipsoid to ovoid, globose or subglobose. The results indicate that characters such as seed size, shape and color are useless for identification of the taxa at the species level. However, the anticlinal wall pattern and periclinal wall ornamentation proved useful for identifying the different genera. Four morphological types could be distinguished: smooth, perforate, microfibrillar and granulate. Type I corresponds to the genus Cistanche and Orobanche anatolica, whereas types II, III and IV were found in Diphelypaea, Orobanche and Phelipanche, respectively. The utility of seed characteristics is discussed in terms of inter‐ and intra‐generic taxonomy.  相似文献   

5.
Muasya. A. M. & Baauar, S. R. 1995. Taxonomic studies in the Fuirena pubescens complex (Cyperaceae) in Kenya. — Nord. J. Bot. 15: 407–410. Copenhagen. ISSN 0107–055X.
Three taxa in the Fuirena pubescens complex were investigated morphologically, palynologically, and cytologically in order to determine their taxonomic identity and appropriate rank. The taxa differ in both morphology and chromosome number. The three former varieties, F. pubescens var. pubescens , var. major , and var. buchananii , are here recognised as distinct species, with var. major and var. buchananii being reinstated as F. pachyrrhiza and F. welwitschii , respectively. Fuirena pubescens and F. pachyrrhiza have terete spikelets and leaf blades more than 5 mm wide, but the former has a meiotic chromosome number of n=21 and white entire nutlets, while the latter has a chromosome number of n=24 and dark-greenish tuberculate nutlets. Fuirena welwitschii is distinguished by having a 5-angular spikelets, chromosome number n=40, and brownish tuberculate nutlets.  相似文献   

6.
Trigonotis jiaochengensis Q. R. Liu & R. Y. Yan, a new species from Shanxi, China, is described and illustrated here. It is similar to T. peduncularis in having multiple diffuse stems, ovate to elliptic leaf blades, scorpioid cyme with only basal bracts and trigonous‐tetrahedral nutlets, but differs in having slender pedicels that are 5.2–18.4 mm long (vs clavate pedicels 1.5–4.8 mm in T. peduncularis), smooth nutlets with a short carpophore and a flat bottom (vs verrucose nutlets with a long carpophore and convex bottom in T. peduncularis). Morphological characters, including pollen and nutlets, with illustrations, diagnostic comparisons and habitat, are presented.  相似文献   

7.
The micro‐morphology of nutlets in 30 taxa (28 species and 2 varieties) of Microula Benth. (Boraginaceae) was surveyed by light and scanning electron microscopy. A principal coordinate‐based ordination analysis (PCO) (8 morphological and 14 micro‐morphological characters) was applied to explore whether taxa clustered according to the current sectional taxonomy. The nutlet epidermis showed three major features: trichomes, papillae and lamellae. Two basic trichome types could be identified: branched and unbranched. Stellate trichomes (STT) and stipitate stellate trichomes (SST) can be considered as two subtypes of branched trichomes based on shape and branching location. Three kinds of unbranched trichomes were recognized by their shapes: slender trichomes (SLT), spear‐like trichomes (SPT) and conical trichomes (CT). Four types of papillae were revealed in this genus: central apiculate papillae (CAP), debris‐covered convex papillae (DCP), rugous papillae (RP) and tabular papillae (TP). The lamellae was classified in five types: glossy lamellae (GL), thread‐like lamellae (TL), rugous lamellae (RL), interrupted lamellae (IL) and debris‐covered lamellae (DCL). The variation in the nature of surface sculpturing, nutlet shape and size, dorsal aperture shape, and attachment scar positions proved useful diagnostic characters. Taxa belonging to the same section generally clustered together in the PCO analysis. A key based on the morphology and micro‐morphology of nutlets is provided to distinguish the sections of Microula. The presence of SLT, STT, DCP and DCL is consistent with the macro‐morphological classification and provides additional evidence for the subgeneric delimitations. The SST, SLT, CAP, DCP, RP, DCL, GL and RL are useful in discriminating species in Microula. Additionally, the distribution of some trichomes, papillae and lamellae types is correlated with the altitudinal distribution of the species.  相似文献   

8.
Morphological characters of the nutlets of Cyclotrichium Manden. & Scheng. in Turkey were examined using scanning electron microscopy (SEM). The genus Cyclotrichium is represented by six species in Turkey, of which two are endemic for Turkey. Nutlet morphology of the species was studied using stereoscopic microscopy and SEM, and the features were described and illustrated. Nutlet morphology of the examined specimens exhibits some variation in size, shape and sculpture. Nutlets range from 1.1 to 2.0 mm in length and 0.5 to 1.0 mm in width and are elliptic, oblong to ovoid and trigonous in shape. Nutlet sculpture can be divided into two main types: distinctly or weakly reticulate pattern in C. niveum, C. origanifolium, C. longiflorum and rounded cell arrangement in the remaining species. Micromorphological characters could be useful in solving taxonomic problems of Cyclotrichium.  相似文献   

9.
采用扫描电镜方法对井冈山地区18种唇形科植物的果实形状与表面微形态特征进行观察比较。结果表明:18种唇形科植物果实形状多样,可分为矩圆形、圆形、卵形、三棱形、球形和椭圆形6类;外果皮表面细胞形状为4~6边形、不规则形和细胞形状不可见;依据外果皮表面凸起度可分为平滑型、凹陷型和凸起型3类;外果皮表面蜡质纹饰复杂多样,有平滑无纹饰、负网状纹饰、网状纹饰兼具疣状或瘤状凸起和网状纹饰兼具次级条纹4类;外果皮表面附属结构主要包括表皮毛和丝状结构,并具有或多或少的鳞片状或颗粒状分泌物。18种唇形科植物果实形状和外果皮表面微形态特征均表现出丰富的多样性,可为唇形科属间和种间亲缘关系研究提供重要的分类学依据。  相似文献   

10.
Teucrium montanum L. and T. polium L. are the two closest Teucrium L. species from sect. Polium (Mill.) Schreb in Turkey. In addition, they are sympatric for some part of their range in Turkey. In this study, comparative anatomical and micromorphological studies of the two species are carried out. They have been investigated by their leaf and stem anatomical features, as well as nutlet micromorphological characteristics. The results of anatomical studies show that the anatomical characters of both taxa are observed to be similar to the general features of the family Lamiaceae anatomy, except for lacking rich collenchyma at the corners. Both taxa are similar in stem anatomy and their leaves exhibit xeromorphy. However, trichome morphology on the stems and the leaves appear to have a taxonomic value in segregation of the two taxa. Light and scanning electron microscope studies on the nutlets also show that nutlet shapes, measures and surface micromorphologies are different in the two species. Whereas nutlet surfaces are bireticulate in both species, the nutlets are larger and primary sculpturing is more distinct in T. polium than in T. montanum. Moreover, the nutlets are oblong to oblong-ovoid and larger in T. polium, but ovoid and smaller in T. montanum.  相似文献   

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12.
师雄  杨鲁红  陈茜 《广西植物》2017,37(11):1455-1462
利用光镜和扫描电镜,对石韦属(Pyrrosia)19种植物的孢子纹饰进行了研究。结果表明:19种石韦属孢子都为黄色,形态均为肾形,两侧对称,单裂缝,说明该属植物是一个自然类群。表面纹饰类型有3种,即瘤状、瘤状—疣状和瘤状—网脊状。孢子表面纹饰特征性状稳定,在种间存在较大差异。该研究结果可以为形态近似种的分类提供参考依据,同时也为石韦属属下分类系统的建立提供了重要证据。  相似文献   

13.
何红燕  熊源新  石磊  贾鹏 《广西植物》2011,31(2):188-193
利用扫描电镜观察了八种青藓科植物孢子及蒴齿的形态,青藓科植物的孢子纹饰多以芽孢状和瘤状突起为主,孢子的大小、外壁纹饰的差异显示了不同种之间的遗传分化及系统演化。青藓属外齿层腹面中部分为四种类型:光滑无疣、颗粒状疣、短刺状小疣、棒状和芽孢状疣,外齿层中上部的特征属与属之间存在差异,该研究可为分类鉴定提供一定的依据。  相似文献   

14.
Hymenochaete rhododendricola sp. nov. and Hymenochaete quercicola sp. nov. are described from Xizang Autonomous Region (Tibet), southwestern China. Hymenochaete rhododendricola is distinct in the genus by its large and heavily enmeshed setae, and growing on dead branches of Rhododendron. Hymenochaete quercicola differs from other species by its smooth or tuberculate hymenophore, presence of a cortex, relatively large and oblong‐ellipsoid basidiospores, and living on dead branches of Quercus.  相似文献   

15.
Wild and cultured specimens of Prorocentrum lima (Ehrenb.) F. Stein from 26 widely different areas in 13 countries were examined in order to determine consistent characters for delimiting species boundaries in this taxon. The morphological characters valve shape, valve size, valve ornamentation, number and shape of valve pores, number and shape of marginal pores, and periflagellar platelets were observed using LM and SEM, and two molecular genetic regions were sequenced. We identified stable morphological characters that were consistent among wild specimens and all cultures, which were valve shape, valve ornamentation, and number and arrangement of periflagellar platelets. All cultures of P. lima identified by these characters formed a monophyletic group in phylogenetic analyses based on the two genes, which, however, included the species Prorocentrum arenarium. P. arenarium was determined to be within the range of morphological variation of P. lima, and therefore we synonymize the two taxa. Within this monophyletic group, P. lima was divided into several subclades in the all phylogenetic analyses. There were no morphological characters specifically related to any one subclade. The subclades appeared to correlate broadly to sample collection regions, suggesting that geographically separated populations may have become genetically distinct within this epi‐benthic species. We have emended species boundaries in P. lima.  相似文献   

16.
The pollen morphology of forty taxa of the genus Nepeta L. was studied and documented in detail using light microscopy (LM) and scanning electron (SEM) microscopy in this study. Nepeta L. pollen grains are small to large (P = 18.64–63.46 μm, E = 15.62–46.33 μm), suboblate to perprolate (P/E = 0.86–2.09) in shape and hexacolpate (very rarely tetracolpate) with granular membranes. Alternate position of colpi occurs in six Nepeta taxa, N. nuda ssp. glandulifera, N. concolor, N. crinita, N. congesta var. cryptantha, N. stricta var. stricta and N. sibthorpii ssp. tumeniana. In examinations of exine ornamentation with SEM, two types of pollen grains were recognized: (1) type I, with microreticulate sculpture; and (2) type II with bireticulate sculpture, type I and II to be divided into two and five subtypes, respectively. In the two taxa with microreticulate pattern, N. pilinux and N. sulfuriflora, a tendency towards a bireticulum could be recognized due to traces of secondary tectal connections. The bireticulate exine ornamentation is characterized with varying characteristics of the primary muri and secondary reticulum. Pollen morphology within the genus is compared with infrageneric relationships.  相似文献   

17.
利用扫描电镜技术对伞形科山芹属(Ostericum Hoffm.)9种2变种(21居群)植物叶表皮微形态特征进行了观察分析。结果显示:山芹属植物叶片上表皮表面均较平滑,细胞轮廓清晰或不清晰,若细胞轮廓可见则为多边形与不规则形;初级蜡质纹饰为较密集的粗(细)条状,部分种类具有单层或双层脊状二级纹饰或有颗粒状或分枝状附属结构;下表皮亦有类似蜡质条状纹饰,均匀分布或集中在气孔周围或凹凸部位,气孔器形状多为椭圆形(偶见梭形),内外拱盖表面粗糙或光滑。上述研究表明,山芹属叶片微形态特征具有良好的种内稳定性和种间多样性,尤其是初级纹饰的宽度及排列密度、二级纹饰以及气孔器形状等特征,可为山芹属植物种间和种下的近缘类群亲缘关系与分类修订提供形态学依据。  相似文献   

18.
蕨类植物孢子表面的纹饰形态复杂多样, 在分类学和古生物学研究中具有重要意义, 目前探索祖先性状演化常用形态学与系统发育学结合的方法。本文选取一回羽叶铁线蕨类植物为材料, 用扫描电子显微镜观察其孢子形态, 用5个叶绿体基因序列构建系统树, 用最大似然法和最大简约法来分析孢子性状的演化。结果表明: 一回羽叶铁线蕨类的孢子纹饰有5种类型, 即光滑、粗糙、颗粒、疣状及瘤状; 这一类群的祖先孢子纹饰有很大的可能是瘤状纹饰; 疣状纹饰可能是由瘤状纹饰演化而来; 孢子纹饰由简单向复杂演化, 越进化的物种其孢子纹饰越复杂。  相似文献   

19.
A new benthic dinoflagellate species, Prorocentrum bimaculatum sp. nov., is studied from Kuwait’s marine sediments, based on detailed morphological and molecular data. Cells are large, oblong oval in shape. They are 49.9–55.3 μm long and 38.4–43.2 μm wide. The ornamentation of this new species is peculiar, and characterized by smooth valves with large pores (0.32–0.50 μm) scattered on their surface, except in two circular patches of ~15 μm in diameter, devoid of ornamentation and located on both sides of the valve centers. The periflagellar area is widely triangular, located in a moderate excavation of the right valve, and comprises nine platelets. The intercalary band of P. bimaculatum is smooth. The molecular phylogenetic position of this new taxon was inferred from SSU and LSU rDNA genes. In both phylogenetic analyses, P. bimaculatum branched with high support with Prorocentrum consutum and formed a clade sister to the one including P. lima and related species such as P. arenarium, P. belizeanum, P. hoffmannianum, and P. maculosum. From the phylogenetic study, since most species related to P. bimaculatum are known for their toxic effects and production of okadaic acid, this new species can be considered as a potential toxin producer, but this has to be analyzed.  相似文献   

20.
本文报道了在立体显微镜和扫描电子显微镜下对福建荸荠属8种、1变种植物果实表皮微形态特征的观察结果。根据果皮纹饰的不同,可分为两种类型:网状纹饰、拟网状纹饰;荸荠属植物果实表皮微形态特征具有丰富的多样性,表型可塑性小,不同类群之间具有明显的种间差异。观察结果表明:荸荠属果实表皮微形态特征是该属分类与系统研究中不可忽视的性状。  相似文献   

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