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1.
Scanning electron microscopy was used to examine stem, leaf, staminal and stylar hairs on species belonging to Solanum L. section Solanum. The surface morphology of these hairs is illustrated. Simple, uniseriate hairs characterize the section Solanum, and these may have eglandular or glandular heads; they are usually multicellular, but in some species the stylar hairs appear to be unicellular. In addition, stalked glands, described here as spherical, four-celled glands, are universally present in species belonging to the section Solanum.  相似文献   

2.
J. M. EDMONDS, 1984. Pollen morphology of Solanum L. section Solnnum . The pollen morphology of both dried and fresh, fixed material was examined using SEM. The work confirmed thc spheroidal to sub-prolate shape, the tricolporate nature and the granular surface sculpturing, typical of Solanurn pollen, but failed to demonstrate the occurrence of exine patterns which could bc of practical taxonomic use is differentiating the species belonging to the section Solanurn . Quantification of the exine sculpturing, by means of granule density counts, indicated a possible relationship between this feature and the morpho-genetic diversity of certain species.  相似文献   

3.
4.
The bat skin shows an unusual morphology that corresponds to flying adaptations but also performs multiple functions including a protective barrier against microbes and parasites. Here, we compare the microscopic structure of the skin and hairs collected from the membranes with other body parts in the Common Pipistrelle (Pipistrellus pipistrellus) in relation to parasite availability. Statistical analysis of whole‐skin thickness revealed two main groups according to body regions; the first with thin skin (wing and tail membrane) and the second with thick skin (head and dorsum, abdomen, footpad). The density of hair was evaluated by a novel method, and it revealed that the density was significantly higher in the head region than in dorsal and ventral body parts. These differences possibly play a role for bat ectoparasites when choosing the preferred region of their host. Along the axis of each hair, the scale morphology was found to be variable. Hair morphology, however, did not vary among body regions. Mast cells were numerous in the hairy areas around vessels and hair follicles of the dorsum and abdomen, which are easily accessible to ectoparasites. Increased numbers of mast cells in hair‐bearing skin are part of the host adaptation system in parasite‐preferred locations.  相似文献   

5.
An investigation of species of the Antirrhineae (Scrophulariaceae), primarily from the point of view of seed morphology, has indicated that the inclusion of Linaria chalepensis and L. armeniaca in section Versicolores is unsatisfactory. Several unusual features of both the seeds and other parts of the plants provide a basis for recognizing a distinct section to include these two species. An overlooked infrageneric taxon of Linaria has been reinstated as section Macrocentrum (C. Koch) D. Sutton. All taxa included in this section are described and illustrated. The significance of the unusual seed morphology is discussed in relation to the affinities of the genus.  相似文献   

6.
The pollen morphology of Phyllanthus (Euphorbiaceae) section Choretropsis   总被引:1,自引:0,他引:1  
The pollen grain morphology of the eight South American species of the genus Phyllanthus , subgenus Phyllanthus , section Choretropsis , endemic to Brazil, was investigated using light and scanning electron microscopy. The high homogeneity in pollen shape, as well as aperture number and configuration, allowed the definition of a basic pollen type for this section, viz. prolate spheroidal or subprolate, zonocolporate with 4–5 invaginated colpi, sexine reticulate. Two subtypes have been observed, based on pollen grain apertures and exine sculpture. The first subtype is characterized by straight and narrow colpi provided with costae, lalongate endoapertures and a reticulum of rectilineous muri as in P. choretroides and P. spartioides . The second subtype has wider colpi without costae, circular endoapertures and a reticulum with curvilineous muri as in P. flagelliformis , P. goianensis and P. scoparius , or curvilineous-rectilineous muri as in P. angustissimus , P. gladiatus and P. klotzschianus . It was demonstrated that the pollen shape and the number of colpi varied within and between some of the species. The results suggest that pollen grain morphology, in association with plant architecture and the presence of phylloclades, constitute additional evidence to delimit the species of the section Choretropsis and to further understand their evolutionary origin within the genus Phyllanthus.  © 2004 The Linnean Society of London, Botanical Journal of the Linnean Society , 2004, 144 , 243–250.  相似文献   

7.
The pollen morphology of 32 species of the genus Vicia was studied using scanning and transmission electron microscope (SEM and TEM). The interstitia of the pollen of the examined species were found to be either regular columellate, irregular columellate, or granular. The granular pattern was recognized to be apomorphy against the columellate patterns in the tribe Vicieae by comparison with the pollen in the tribes Vicieae, Cicereae, Galegeae, Hedysareae, and Trifolieae. The group of Vicia species having the apomorphy was congruent with that having a known apomorphy of the pistil character. This group with such synapomorphies may be monophyletic, though it is treated as polyphyletic in the present infrageneric system of Vicia.  相似文献   

8.
Alternanthera (Amaranthaceae) is a diverse genus largely restricted to the American Tropics that belongs to the alternantheroid clade containing C4 and C3–C4 intermediate species. This research focuses on the study of pollen characters by studying 13 species, representatives of the two major clades and subclades of Alternanthera. General palynological comparisons were conducted with light microscopy (LM), scanning electron microscopy (SEM) and with confocal laser scanning microscopy (CLSM) for exine ultrastructure. Twenty-five characters were measured and described for Alternanthera and among these, 14 pollen characters were used to discriminate pollen groups using cluster analysis and canonical analysis of principal coordinates (CAP). Pollen form and ornamentation, pores number, spines length, number of ektexinous bodies and nanospines on the ektexinous bodies on pore membranes, arrangement of nanopores and spines on structural elements, and metareticula form were taxonomically important and therefore used to construct the first palynological key to the alternantheroid clade species. Our study indicates that the seemingly subtle morphological variation of pollen is useful for recognising three main pollen types within Alternanthera. The much needed palynological terminology for describing the mesoporium in the metareticulate pollen of Amaranthaceae is provided.  相似文献   

9.
REJDALI, M., 1990. Seed morphology and taxonomy of the North African species of Sideritis L. (Lamiaceae). Seed morphology data are shown to support data from general morphology and palynology; they can be used for taxonomy at the sectional and specific levels. At times clear differences are apparent at the infraspecific level. Seed sculpturing was found to be of great value for separating taxa at all levels of the hierarchy.  相似文献   

10.
The discovery of an earlier epithet for the eglandular-haired subspecies of the Eurasian tetraploid Solarium villosum Miller has necessitated a name change and a new combination. The taxon previously called S. villosum Miller subsp. puniceum (Kirschl.) Edmonds now becomes S. villosum subsp. miniatum (Bernh. ex Willd.) Edmonds. Additional synonyms of this subspecies are given, together with the reasons for the selection of the epithet 'miniatum' rather than 'humile' which was published at the same time.  相似文献   

11.
A palynological study of the genus Mentha L. (Lamiaceae)   总被引:1,自引:0,他引:1  
The pollen morphology and exine structure of 10 Mentha L . species were investigated using light microscopy and scanning electron microscopy. The pollen grains of all 11 species were hexazonocolpate with granular membranes and a circular amb, varying in shape from prolate-spheroidal to suboblate. Different colpus shapes were recognized in M . ×  dumetorum . The exine was bireticulate in section Pulegium , and reticulate in section Menthae . A correlation was found between pollen size and chromosome number. The results indicate that the pollen characters of the genus Mentha are valuable for taxonomic applications and may be useful for classification.  © 2008 Uludag University. Journal compilation © 2008 The Linnean Society of London, Botanical Journal of the Linnean Society , 2008, 157 , 141–154.  相似文献   

12.
PANIGRAHI, S. G., 1986. Seed morphology of Rotala L., Ammannia L., Nesaea Kunth and Hionanthera Fernandes & Diniz (Lythraceae) . Seed-surface characteristics of Ammonia lalifolia L., Rotala verticillaris L., Nesaea triflora Comm. ex Kunth and Hionanthera garciae Fernandes & Dinz were studied using the SEM. Seeds from herbarium specimens moistened in water produce cracks along the intercellular walls and distinctive types of invaginating 'hairs'. These 'hairs' are mucilaginous in nature and diagnostic at the species level. They are released in profusion from the upper convex surface of the testa. Viable seeds of Ammonia baccifera L., similarly treated, exude, in addition to the 'hairs', mucilaginous globules from the lower concave surface during germination. The invaginating 'hairs' arise diagonally from the roof of the epidermal cells of the testa and protrude to the lumen of the epidermal cells. A sac of mucilage is observed swelling out on the inner flat surface of the developing seeds. The biological functions of these 'hairs' and mucilage globules in germinating seeds in relation to seed dispersal and regulation of germination in appropriate habitats is discussed.  相似文献   

13.
The stigma of 31 taxa of Aylostera (Cactaceae) was studied using environmental scanning electron microscopy. Seven stigma types could be defined, based on the degree of fusion of the stigmatic lobes and, when these are completely separated (types I and II), their orientation. Four types (types IV, V, VI and VII) are present only in Aylostera subg. Mediolobivia, two of which (types IV and VII) are species-specific. Stigma morphology was found to be a good diagnostic character in Aylostera subg. Mediolobivia, allowing in some cases to distinguish species that had been confused previously. The stigmatic types here defined seem apt to characterize natural groups within the subgenus and are useful as an aid for species identification and the characterization of new taxa.  相似文献   

14.
The morphology of all larval instars of Fannia canicularis (Linnaeus) (Diptera: Fanniidae) is documented using a combination of light and scanning electron microscopy. The following structures are documented for all instars: antennal complex; maxillary palpus; facial mask; cephaloskeleton; ventral organ; anterior spiracle; Keilin's organ; posterior spiracle; fleshy processes, and anal pad. Structures reported for the first time for all instars include: two pairs of lateral prominences on the prothoracic segment; additional ventrolateral prominences on the second thoracic segment, and a papilla at the base of the posterior spiracle. Other structures reported for the first time are anterior spiracles in the first instar and a serrated tip on the mouthhook in the second instar. A trichoid sensillum on the posterior spiracular plate, representing a sensory organ otherwise unknown in the Calyptratae, is described in the second and third instars. Results are discussed and compared with existing knowledge on dipteran larval morphology.  相似文献   

15.
Seed coat structure in Solanum L. section Solanum (Solanaceae). Seed coat structure in Solanum L. section Solanum was examined using SEM. The seed coat patterns observed were fairly uniform throughout the section, and thus of little diagnostic use. Moreover, all species are characterized by their seeds being covered by hairlike structures, which are bands of lignified thickening in the lateral (and basal) walls of the outer epidermal cells of the testa, and which only become obvious when the seeds are wetted. The development of the seed coat and its characteristic thickening was followed from the unfertilized ovule to the mature seed in vouchered material of Solanum nigrum L. since this species is the generic type, using sections of freshly fixed material.  相似文献   

16.
Structural and trace element changes in scalp hair of radiographers   总被引:1,自引:0,他引:1  
Scalp hair samples were collected from medical radiographers and nonradiographers of matching age groups. Structural morphology of hair was studied by scanning electron microscopy, and the trace element profiles in hair were measured using neutron activation analysis. The structural damage to the hair follicles of the radiographers was quite obvious, and this may be a good qualitative indicator of radiation damage at low doses. The concentrations of aluminum (Al), potassium (K), and vanadium (V) in hair of the radiographers were significantly higher, whereas those of antimony (Sb) and magnesium (Mg) were significantly lower than those of nonradiographers. Some of our findings were quite consistent with those of others in determining the changes in trace element concentrations in irradiated tissue.  相似文献   

17.
A new subfamily, Pararotylenchinae, (Hoplolaimidae) is described. It includes a single genus, Pararotylenchus n. gen., six new species, attd two new combinations, Pararotylenchus (syn. Tylenchorhynchus) brevicaudatus (Hopper, 1959) n. comb. and Pararotylenchus (syn. Rotylenchus) pint (Mamiya, 1968) n. comb. Pararotylenchinae is similar to certain other Hoplolaimidae, such as Rotylenchinae, with respect to most characters including the short tail, the position of the phasmids near the anus, and the relatively great distance of the dorsal gland orifice from the base of the stylet knobs. The lip region, as observed with the scanning electron microscope, conforms to the basic pattern for Hoplolaimidae. The labial disc is round with slit-like amphidial openings at the lateral sides of the periphery of the disc. The distinctive anterior-most lip annule is segmented into six sectors. Unlike other Hoplolaimidae, however, the esophageal glands of Pararotylenchinae form a basal bulb similar to that of Tylenchorhynchidae; other characters do not resemble Tylencborhynchidae. Specimens of Pararotylenchus have been recovered only from cool regions at high elevations and Pacific coastal areas in the Western United States, Japan, and Korea.  相似文献   

18.
The nomenclatural changes which have become necessary for several species belonging to Solanum section Solanum since they were revised during the preparation of Flora Europaea are given and discussed. S. villosum is now recognized as the correct name for S. luteum , and this has necessitated a new combination for the eglandular subspecies of this taxon, namely, S. villosum Miller subsp. puniceum (Kirschleger) Edmonds. The two species were described simultaneously by Miller, and the precedence of the epithet villosum over the epithet luteum is fully discussed, together with the reasons for the selection of puniceum as the second subspecific name. The species previously referred to as S. melanocerasum is now known to be synonymous with S. scabrum , while S. chenopodioides becomes the correct name for S. sublobatum. Complete lists of synonyms are given for these three species, together with extensive notes on the more controversial and difficult synonymy. Finally, reasons are given to justify the spelling of S. sarrachoides with two r's.  相似文献   

19.
广西蕨类植物孢子形态的研究Ⅰ.水龙骨科   总被引:1,自引:1,他引:1  
该文是广西蕨类植物孢子形态研究的第一部分。首次利用光学显微镜和扫描电子显微镜对广西产水龙骨科6属9种植物的孢子形态进行了观察研究。对每个种的孢子形态特征及表面纹饰进行了描述。水龙骨科6属9种植物孢子都为单裂缝类型孢子,孢子外壁表面具有皱状、细孔状、蠕虫状、瘤状、光滑、索状条纹和颗粒状纹饰7种纹饰类型。讨论了各属、种问的差异,为水龙骨科系统分类及孢粉学研究提供资料。  相似文献   

20.
In the lactating breast, the development of secretory alveoli consisting of differentiated cells arranged around a central lumen is dependent on signals from the extracellular environment of the cells. There are few cell lines that model this process. We previously showed that the human breast carcinoma line PMC42-LA can be induced to form organoids, reminiscent of secretory alveoli found in the lactating human breast. In this report, we used high-resolution scanning electron microscopy to show that the formation of organoids is accompanied by development of cell surface microvilli. Extracellular matrix-induced formation of microvilli occurred on the internal and external surfaces of cells in the organoids and not on surfaces in contact with the extracellular matrix. Organoid formation of PMC42-LA cells induced a rearrangement of the extracellular matrix, seen in the form of radiating fibers from the organoids. In summary, there is an interaction between PMC42-LA cells and the underlying extracellular matrix, which leads to the formation of polarized cells with well-developed microvilli. This is accompanied by organization of the extracellular matrix. PMC42-LA is a relevant model of the human breast for investigations into cell-cell and cell-matrix interactions.  相似文献   

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