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1.
Nutlet sculpturing of 22 taxa ofScutellaria sect.Resinosa, representing 18 of its 19 species, and the monotypic genusSalazaria was studied by scanning electron microscopy (SEM). The nutlets of sect.Resinosa, while remarkably variable among themselves, differed from hypothetically closely related sections in lacking circumferential banding and sessile glands. Species could be grouped by surface sculpturing into seemingly meaningful phenetic clusters.Scutellaria potosina var.platyphylla was sufficiently distinct micromorphically so as to be elevated to specific status asScutellaria platyphylla comb. and stat. nov. The significance of nutlet microcharacters within sect.Resinosa is discussed, especially as compared to closely related sections. The genusSalazaria had nutlet sculpturing quite different from all taxa belonging to sect.Resinosa.  相似文献   

2.
A comprehensive study on nutlet morphology on 46 taxa from the tribe Elsholtzieae was conducted using stereomicroscopy, light microscopy and scanning electron microscopy. The objectives were to evaluate the nutlet characteristics in a systematics context and to provide additional evidence for taxon delimitation. The nutlet shape varied from elliptical, widely elliptical, spheroidal and ovate to pyriform. The size ranged from 0.50 to 2.70 mm in length and 0.34 to 2.65 mm in width. The three types of trichomes included simple non-glandular trichomes (Collinsonia punctata), clavate non-glandular trichomes (Elsholtzia cephalantha) and peltate glandular trichomes (Mosla grosseserrata and M. chinensis). We also report the presence of a mucilaginous reaction in nine species of the genus Elsholtzia in Elsholtzieae for the first time. Four types (undulate, papillae-like projection, thorn-like pattern and reticulate) and three subtypes (reticulate, reticulate-cellular and supra-reticulate) of nutlet surface patterns in the mid-ventral region were recognized in Elsholtzieae based on the differences in cell outline, outer periclinal walls and dentations of the anticlinal walls. These nutlet micromorphological results may serve as a reference for future hypotheses on the classification of the tribe Elsholtzieae.  相似文献   

3.
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   

4.
Nutlet sculpturing of 23Teucrium species belonging to six sections was studied. The nutlets of analysed species were characterized by the presence of the oil glands of various density. SectionTeucrium is well defined by very densely distributed trichomes and oil glands on nutlets. Trichomes on nutlets were absent in all other species, except inT. marum from sect.Chamaedrys. Sect.Polium is a homogeneous group, distinguished from the other sections. There are some similarities of this sect. with sect.Scordium. Species of sect.Chamaedrys are heterogeneous and overlap according to the surface sculpturing characters with the other sections. The significance of nutlet microcharacters as additional taxonomical markers in the infrageneric classification of the genusTeucrium is discussed.  相似文献   

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7.
To evaluate nutlets characteristics for systematic relationships, a comprehensive morphological and micro‐morphological study of the nutlets of 16 Iranian taxa of Nepeta (Lamiaceae) was conducted using scanning electron microscopy (SEM). Differences in surface ornamentation, size, shape and color were observed between the species. The studied taxa were categorized in two basic types based on surface ornamentation: non‐sculptured (smooth‐type) and sculptured nutlets. The non‐sculptured nutlets type could be further divided into four sub‐types, including smooth, granulate, undulate‐cellular and reticulate. In the sculptured nutlets, three subtypes of tuberculate, tuberculate‐cellular and verrucate were recognized. The shape of nutlets were described as oblong, ovoid‐oblong, oblong‐linear, to elliptic‐oblong and their size range are 1.2–2.0 mm in length and 0.5–2.0 mm in width. Based on micrographs, the areole form and location were defined as bi‐lobed, straight, basal, sub‐basal or lateral. Nutlet micromorphological characteristics such as surface ornamentation can be useful for classification and identification of e.g. medicinal species of Nepeta in Iran.  相似文献   

8.
Pollen grains of 30 taxa of the genus Stachys (29 spp. and one subsp.), representing 9 of the currently recognized sections and 1 species of the closely related genus Sideritis (Si. montana) distributed in Iran were examined by light and scanning electron microscopy. Twenty-eight taxa are studied for the first time under aspects of pollen morphology. The basic shape of the pollen grains in most taxa studied is prolate-spheroidal, but subprolate, spheroidal and oblate-spheroidal pollen grains can also be found in few species. The grains are usually tricolpate (the amb triangular), but also tetracolpate (the amb circular to more or less square) in some species (S. iberica, S. atherocalyx and Si. montana). The surface is microreticulate (the frequent type), reticulate, perforate, foveolate-psilate or foveolate. The lumina are separated by smooth or sinuate muri which make them polygonal, more or less rounded and elongate. Major pollen morphological features of the taxa studied are compared and discussed on the basis of taxonomical concepts. In some cases, these characters are useful in delimitation of formerly introduced sections while they mostly provide further characters in separating related species from each other. For example, all members of S. sect. Aucheriana are characterized by elongated lumina. Based on the oblate-spheroidal shape of its pollen as well as tetracolpate aperture type, the results of the present study confirm sect. Pontostachys as including S. angustifolia, S. iberica, S. sparsipilosa as well as S. atherocalyx. Our results also suggest that although some species like S. fruticolosa and S. lavandulifolia are morphologically well characterized, they cannot be separated from other species of Stachys based on pollen morphology.  相似文献   

9.
报道了中国唇形科(Lamiaceae)刺蕊草属一新记录种--香薷状刺蕊草(Pogostemon elsholtzioides Benth.),该种在中国产于西藏墨脱县,凭证标本保存在PE。该种在喜马拉雅地区分布广泛,与特产于云南西北部地区的狭叶刺蕊草(P. dielsianus Dunn)的主要区别为:花萼钟形,长3~3.5 mm,花萼齿长为花萼筒的1/3~1/2,花冠长约4.5 mm。  相似文献   

10.
Pollen grains of 30 taxa of the genus Salvia, belonging to sections Salvia, Horminum, Drymosphace, Plethiosphace and Hemisphace from Turkey were examined by light (LM) and scanning electron microscopy (SEM). Detailed pollen morphological characteristics are provided for these taxa. Among the studied taxa, S. verticillata subsp. verticillata from sect. Hemisphace has the smallest pollen grains, and S. pachystachys from sect. Salvia possesses the largest ones. The basic shape of the pollen grains in most taxa is suboblate, oblate-spheroidal or prolate-spheroidal. However subprolate pollen grains are recorded for S. macrochlamys from sect. Salvia. The grains are hexacolpate in all taxa, but in S. recognita from sect. Salvia also octacolpate pollen was found. Three distinct exine sculpturing types exist, reticulate-perforate (the common type), reticulate-granulate and bireticulate. The reticulate-perforate and bireticulate sculpturing patterns can be divided into subtypes based on the number of perforations and the number of secondary lumina in each primary lumen. Pollen morphological characteristics of the taxa studied are compared and discussed on the basis of taxonomical concepts. In some cases, these characters are useful in distinguishing the sections. For instance, the presence of 1-2 large central secondary lumina per primary lumen is a significant character of sect. Horminum separating it from the other sections. As well, the presence of holes on colpus membrane ornamentation can be used as a diagnostic taxonomic character for sectional division between sect. Hemisphace and others. S. ballsiana from sect. Salvia is clearly distinct from the other taxa examined by its unique pollen morphology. Further, for several macromorphologically similar taxa pollen structures provide additional evidence to delimite them from each other.  相似文献   

11.
Morphological and micromorphological characters of the nutlets of ten Onosma species in Turkey were reported. Studied fruit surfaces show some variations. Based on the structure and patterns of epidermis cells of the nutlets, two principal types can be distinguished. In Type 1, the epidermal cells of the nutlet surface are formed in a reticulate pattern with varied sizes and shapes of the meshes. This type is the most common type in the studied species. Seven of the species observed belong to the reticulate type, i.e. O. bracteosum, O. mutabile, O. aleppicum, O. bornmuelleri, O. aucheranum, O. araraticum and O. tauricum. In Type 2, the epidermal cells of the nutlet surface are formed in an elongated type with varied sizes and shapes. Three of the observed species belong to this type, i.e. O. roussaei, O. isauricum and O. stenolobum. Significant taxonomic differences between species were determined on the surface of the nutlets.  相似文献   

12.
利用扫描电镜对少花薹草组(Carex sect. Paniceae)27种及4变种(东亚14种4变种,北美13种)小坚果形态与微形态特征进行比较观察。结果表明(:1)所有材料小坚果的形状为倒卵球形和钝三棱状,组内很一致,长度为1.53~3.59 mm,同种不同居群个体差异不显著(P>0.05)。(2)表皮细胞一般为五至七边形,偶有四边形或八边形,丝柄薹草(C. rouyana)不同个体间有变异;垂周璧式样直或微波状;硅质台平,偶有凹或略凸,具1个中心体,C. filipes var. kuzakaiensis和C. filipes var. tremula中偶见2个中心体,无卫星体,这些性状种内稳定。(3)利用表皮细胞形状、硅质台凹凸情况和中心体个数对于区分近似种具有价值,如白马薹草(C. baimaensis)和线柄薹草(C. filipes),且可以区分一些种下等级,如线柄薹草及其变种var. kuzakaiensis、var. oligostachys和var. tremula。(4)sect. Paniceae s.s.和sect. Laxiflorae小坚果形态和微形态...  相似文献   

13.
Satureja s.l. (Lamiaceae) is a large complex (ca. 225 spp.) that is variably treated as comprising from one to as many as 17 genera. The North American representatives are usually assigned toCalamintha, Clinopodium, Micromeria, Piloblephis, orSatureja. A recent chloroplast DNA restriction site analysis indicates that inclusion ofSatureja s.str.,Micromeria, andPiloblephis in the group renders it non-monophyletic. After exclusion of these three genera, a study of morphological variation in the remainder of the complex suggests that it is best treated as three genera, two of which do not occur in North America (Cyclotrichium and “Obtegomeria” [Doroszenko, ined., to be validated else-where]). The third comprises ca. 100 species, 11 of them native to North America north of Mexico. WithSatureja s.str. excluded, the name with priority for the latter genus isClinopodium. The indigenous North American species and their more frequently used synonyms are tabulated. A new combination,Clinopodium chandleri, is made.  相似文献   

14.
报道了印度唇形科刺蕊草属一新记录种:长苞刺蕊草,该种在印度产于阿萨姆邦,凭证标本保存于英国皇家植物园爱丁堡植物园标本馆(E)。在形态特征上,该种与中国特有的北刺蕊草相似,但其茎叶被糙硬毛、花萼呈近管状等特征与之相异。  相似文献   

15.
Seeds of eight species ofSilene s. str. in Korea were examined with a dissecting stereomicroscope and a scanning electron microscope (SEM) to evaluate the systematic significance of seed coat microstructure. The seeds ofSilene s. str. were characterized by triangular or reniform shape, planed or concave dorsal surface in outline, tuberculate or colliculate testa, and sinuated cell margin. Based on the degree of grooves and invagination at dorsal surface, the seeds of the examined taxa ofSilene s. str. fall into two distinct groups: (I) dorsal grooves inconspicuous, surface planed (Silene jenisseensis andS. repens), (II) dorsal grooves conspicuous, surface concave (six remaining taxa). Within each group, seeds of all species may be further distinguished based on shape, size, and testa surface sculpturing. A key to the different species or groups of species is provided, and the systematic significance between/among the taxa is also briefly discussed.  相似文献   

16.
A taxonomic treatment ofSalvia sect.Ekmania, a group of tall shrubs endemic to the Caribbean island of Hispaniola, is provided. Morphology, phenology, pollination biology, habitats, and distributions are discussed. Species boundaries are examined using phenetic analysis of morphological data. Eight species are here accepted as belonging to the section. Two recently described species,S. lavendula andS. paryskii, are considered for inclusion in the section, but only the latter appears to be a member.Salvia lachnaiclada andS. ottoschulzii are treated as conspecific.Salvia bahorucona is recognized as a distinct species.  相似文献   

17.
In this study, we comparatively investigated three endemic Salvia species spreading in Erzincan (Turkey) in terms of anatomy and micromorphology. For anatomical investigation, cross sections taken from stems and leaves of the species were examined under light microscope. For micromorphological investigation, epidermal surface and nutlet structure were examined using scanning electron microscopy. The S. euphratica and S. divaricata species were examined anatomically and micromorphologically for the first time, and S. hypargea was examined micromorphologically for the first time. In anatomical examinations, it was seen that stem and leaf structures of the species were similar. In micromorphological analyses, it has been seen that hairiness of the nutlet surface and nutlet ornamentations (verrucate and rugose type) created a difference between the species.  相似文献   

18.
该文报道了发现于北京市密云区的1种被子植物新记录——荨麻叶龙头草[Meehania urticifolia(Miq.)Makino],其所隶属的龙头草属(Meehania Britton)为北京分布新记录。描述了荨麻叶龙头草的形态特征与生境,凭证标本藏于浙江大学标本馆(HZU)。荨麻叶龙头草于1899年首次发现于日本,是东北亚分布植物,此前在中国仅分布于东北。北京云蒙山发现的分布点,显然是该种目前在中国分布最西的分布点,可能于冰川期从东北亚迁移而来。  相似文献   

19.
描述并绘制了越南唇形科一新属及新种:日轮果属(Heliacria Bo Li,C.L.Xiang,T.S.Hoang&Nuraliev)和日轮果(H. maritima Bo Li,C.L.Xiang,T.S.Hoang&Nuraliev)。日轮果属因具攀援藤本习性,花大且花冠为纯白色,花萼近辐射对称、5深裂、裂片长且在果期增大并开展,果实顶端具放射状的瘤状突起等特征而明显区别于黄芩亚科的其他5属。目前,该属仅发现于越南东南部沿海的平定省、富安省、庆和省和宁顺省,常生于海岸边干旱的低地矮林中。  相似文献   

20.
In the temperate region temperature is the main factor influencing the germination period of plant species. The purpose of this study was to examine effects of constant and fluctuating temperatures on dormancy and germination under laboratory and field conditions in the three wetland species Lycopus europaeus, Mentha aquatica and Stachys palustris. The results should give indications if the temperature-dependent regulation of dormancy and germination is phylogenetically constrained. Tests for germination requirements showed a minimum temperature for germination of 9 °C in Mentha and 12 °C in Lycopus and Stachys, and a maximum temperature of 33 °C for Lycopus and 36 °C for Mentha and Stachys. Fluctuating temperatures promoted germination in all three species but the amplitude required for high germination (>50%) differed: it was 8 °C in Mentha, 10 °C in Stachys and 14 °C in Lycopus (mean temperature 22 °C). The effect of temperatures on the level of dormancy was examined in the laboratory by imbibing seeds at temperatures between 3 °C and 18 °C for periods between 2 and 28 weeks, as well as by a 30-month burial period, followed by germination tests at various temperatures, in light and darkness. In the laboratory only low temperatures (≤12 °C) relieved primary dormancy in seeds of Lycopus, while in Mentha and Stachys also higher temperatures lead to an increase of germination. Dormancy was only induced in Lycopus seeds after prolonged imbibition at 12 °C in the laboratory. Buried seeds of all species exhibited annual dormancy cycles with lower germination in summer and higher germination from autumn to spring. Exhumed seeds, however, showed considerable differences in periods of germination success. Dormancy was relieved when ambient temperatures were below 12 °C. Ambient temperatures that caused an induction of dormancy varied depending on species and test condition, but even low temperatures (8 °C) were effective. At high test temperatures (25 °C) in light, exhumed seeds of all three species showed high germination throughout the year. The three species showed various differences in the effects of temperatures on dormancy and germination. Similarities in dormancy and germination found among the species are in common with other spring-germinating species occurring in wetlands, so it seems that the temperature dependent regulation of dormancy and germination are related to habitat and not to phylogenetic relatedness.  相似文献   

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