山东莎草属叶表皮微形态的研究

利用光学显微镜对山东莎草属14个种和1个亚种植物的叶下表皮微形态特征进行研究,结果表明:脉间区长细胞为长筒形、短筒形,少数为近方形,边缘为波状、深波状;无短细胞存在;气孔器副卫细胞为三角形、圆屋顶形至三角形、高圆屋顶形和圆屋顶形;乳突存在于脉区长细胞上;刺毛仅存在于个别种中。根据脉区刺毛的有无,结合外部形态,可以分为有刺毛类型和无刺毛2个类型及4个亚类型。莎草属叶下表皮微形态特征高度一致,表明莎草属是一个自然类群,但在种间存在着一定的差异,可以为种的划分提供参考依据。     

Arthropod touch reception: spider hair sensilla as rapid touch detectors

Wandering spiders like Cupiennius salei are densely covered by tactile hairs. In darkness Cupiennius uses its front legs as tactile feelers. We selected easily identifiable hairs on the tarsus and metatarsus which are stimulated during this behavior to study tactile hair properties. Both the mechanical and electrophysiological hair properties are largely independent of the direction of hair displacement. Restoring torques measure 10(-9) to 10(-8) Nm. The torsional restoring constant S changes non-linearly with deflection angle. It is of the order of 10(-8) Nm/rad, which is about 10,000 times larger than for trichobothria. Angular thresholds for the generation of action potentials are ca.1 degrees. Electrophysiology reveals a slow and a fast sensory cell, differing in adaptation time. Both cells are movement detectors mainly responding to the dynamic phase (velocity) of a stimulus. When applying behaviorally relevant stimulus velocities (up to 11 cm s(-1)) threshold deflection for the elicitation of action potentials and maximum response frequency are reached as early as 1.2 ms after stimulus onset and followed by a rapid decline of impulse frequency. Obviously these hairs inform the spider on the mere presence of a stimulus but not on details of its time-course and spatial orientation.     

中国木兰科植物的叶结构及其油细胞的比较解剖学研究

利用组织透明法、石蜡切片法及薄切片法对木兰科10属82种1亚种植物叶片的结构和油细胞的 分布密度、结构及其在叶肉中的分布进行了比较研究。鹅掌楸亚科和木兰亚科在叶结构上的主要区别是：鹅掌楸亚科两种植物叶的部分下表皮细胞乳突状,且整个细胞外壁只形成一个乳突,而在木兰亚科植物中有单列多细胞或单细胞的表皮毛,却未发现乳突;鹅掌楸亚科植物叶主脉维管组织环分隔呈束状,且其外包被的纤维也排列成束状,而木兰亚科的80种1亚种植物中,叶主脉维管组织连成轮状,其外面也由一圈连续的纤维环所包围。从而支持木兰科中木兰亚科和鹅掌楸亚科两个亚科的划分。并且,从叶主脉的演化趋势来看,鹅掌楸亚科较木兰亚科进化。另外,木莲属植物叶片的结构与木兰属具有明显差异,因而进一步证明木莲属是不同于木兰属的一个独立的属。油细胞是木兰科植物叶片解剖的显著特征,在叶肉中的分布可划分为3种类型：(A)主要分布于栅栏组织;(B)主要分布于海绵组织;(c)均匀散布于整个叶肉中。油细胞的大小及其在叶中的分布与叶厚、栅栏组织层数、栅栏组织与海绵组织厚度间的比值以及下皮层的有无、表皮毛的类型、叶脉的结构等特征相结合,可作为属、甚至种的鉴别特征。     

Comparative studies on leaf structure and oil cells of the Magnoliaceae in China

The leaf structure and morphology, the structure and location of oil cells in leaves of 82 species and 1 subspecies in 10 genera of the Magnoliaceae were comparatively studied using tissue clearing, paraffin sectioning and thin sectioning. In leaves of Liriodendroideae, some of abaxial epidermal cells are papillose and the vascular tissue of the main vein appeared to be separated. However, papillose cells were not found and there were uniseriate, multicellular or unicellular hairs distributed on the epiderm, and the vascular tissue of the main vein appeared to be continuous in leaves of the Magnolioideae. Furthermore, in the Magnolioideae, the structure of leaves of Manglietia were different from that of Magnolia. These results support the separation of Magnolioideae and Liriodendroideae, and suggest that Manglietia and Magnolia be independent genera, which is consistent with Law’ s taxonomic scheme. Oil cells are one of marked features of the leaf anatomy of the Magnoliaceae, and they are mainly distributed in the palisade tissue in leaves of 47 species and in the spongy tissue in leaves of 5 species, and dispersed in the whole mesophyll in leaves of 31 species. The size and location of oil cells in leaves, combined with the thickness of leaves, the number of layers of the palisade tissue, the ratio of palisade tissue to spongy tissue in thickness, the hypo-derm, and the type of hairs may be used as the characteristics of genera and even species.     

Sense organs on the antennal flagellum of a giant cockroach, Gromphadorhina portentosa, and a comparison with those of several other species (Dictyoptera, Blattaria)

Two kinds of tactile hairs, plain and wavy, thick-walled chemoreceptors and two types of thin-walled chemoreceptors are present on the antennal flagellum of Gromphadorhina portentosa males. These are described and their location on the antenna noted. Females of this species have plain tactile hairs and the same types of chemoreceptors as do the males but wavy tactile hairs are absent. The antennal sense organs of a few specimens of five other species of cockroaches — Periplaneta americana, Blatta orientalis, Supella longipalpa, Pycnoscelus surinamensis and Diploptera punctata — were also examined. All lacked tactile hairs but were provided with thick-walled chemoreceptors and with two types of thin-walled chemoreceptors similar to those described for Gromphadorhina portentosa.     

Central organization of common inhibitory motoneurons in the locust: role of afferent signals from leg mechanoreceptors

Intracellular recordings of mesothoracic common inhibitory neurons (CI₁, CI₂ and CI₃) were made while tactile hairs of the middle legs of locusts (Locusta migratoria) were mechanically stimulated. Generally the three common inhibitory neurons were excited by stimulation of tactile hairs on the ventral and dorsal surface of femur and tibia. The response pattern of all three CI neurons was similar suggesting that they work as a functional unit. Touching hairs on the dorsal surface of tibia and tarsus in some cases led to inhibition of CIs. The connection between sensory cells of tactile hairs and common inhibitory neurons is polysynaptic.To identify interneurons which mediate afferent signals, simultaneous intracellular recordings from CIs and interneurons were made. Different spiking interneurons were identified which made excitatory or inhibitory monosynaptic connections with CIs. Interneurons with inhibitory input to CIs belonged to the ventral midline group of spiking local interneurons. Behavioral and electrophysiological results indicate that reflex movements of the leg are accompanied by activity of CI neurons. Further it appears that CI activity is inhibited when reflex movements of the leg are actively suppressed by the animal.Abbreviations CI common inhibitor - IN interneuron - LY Lucifer Yellow     

Leaf micromorphology and taxonomy of North African species of Sideritis L. (Lamiaceae)

REJDALI M., 1991. Leaf micromorphology and taxonomy of North African species of Sideritis L. (Lamiaceae). This study reports on the structure of trichomes, epidermal cells, stomata and venation patterns. The trichomes are either glandular or eglandular. The latter are unicellular or multicellular, soft or rigid pointed hairs. The glandular hairs are short or long stalked, the latter are generally flattened and may be sessile. The epidermal cells are variously shaped with sinuous or straight walls usually randomly orientated. Stomata are either anomocytic or diacytic and evenly distributed throughout the epidermis without any definite pattern of orientation. Venation is of the semicraspedodermous type.     

北京幽灵蛛体表微感受器的类型、结构和分布

北京幽灵蛛(Pholcus beijingensis)体表的微感受器包括毛状感受器(触毛、听毛、味觉毛和刺)、裂缝状感受器(单个裂缝器、竖琴器)和跗节器等.扫描电镜观察显示,北京幽灵蛛体表的毛状感受器数量最多,分布最广;其次是裂缝感受器;此外,每个跗节末端具有一个跗节器.除触毛在整个身体表面均有分布外,其他毛状感受器(...     

The Epidermal Cells of Tea Leaves

The upper epidrmis of tea leaf consists of cells about 30 40 μ in diameter, with slightly sinuous cell surface and devoid of stomata or hairs. The lower epidermis consists of cells about 50–70 μ in diameter, with more sinuous walls. Stomata confined to the lower surface, surrounded by 3–4 round, subsidiary cells. The upper andlower epidermis of the wild tea of southwest China show the difference in surface texture. Luxuriant wax of the epidermis is in knob or club shape. There are two types of stomata (namely general stomata and stomata of sunken crypts (gland scale)) on the same leaf. The numbers of stomata are distributed 70–100/mm2. Hairs are short and rare, or none. Intercellular flanges between epidermis is steep and thick in wild tea. The protruded parts of the torus are in the form of “foot”. The flanges of the cuticle are rather deep.     

Mutations in actin-related proteins 2 and 3 affect cell shape development in Arabidopsis

ACTIN-RELATED PROTEINS 2 and 3 form the major subunits of the ARP2/3 complex, which is known as an important regulator of actin organization in diverse organisms. Here, we report that two genes, WURM and DISTORTED1, which are important for cell shape control in Arabidopsis, encode the plant ARP2 and ARP3 orthologs, respectively. Mutations in these genes result in misdirected expansion of various cell types: trichome expansion is randomized, pavement cells fail to produce lobes, hypocotyl cells curl out of the normal epidermal plane, and root hairs are sinuous. At the subcellular level, cell shape changes are linked to severe filamentous actin aggregation and compromised vacuole fusion. Because all seven subunits of the ARP2/3 complex are present in plants, our data indicate that this complex may play a pivotal role during plant cell morphogenesis.     

Foliar epidermal and stomatal studies ofGlinus lotoides L.

TheGlinus lotoides L. is a amphi-stomatal, amphitrichomic and xeromorphic plant. The stomata are anomocytic and their distribution is of potato type. The stellate hairs are present all over the plant. The configurations of epidermal cells in the leaves are straight and highly sinuous on upper and lower surfaces respectively. The ratio of stomatal indexes between the two surfaces of the leaves is uniform, hence may be used for taxonomic studies     

Differential effects of nitric oxide on the responsiveness of tactile hairs

The responses of tactile hairs located on legs of the desert locust Schistocerca gregaria (Forskål) are modulated by nitric oxide (NO). There are two types of tactile hair on the tibia of the hind leg of the locust which differ in their thresholds for mechanical stimulation, their location on the leg and in the effect of NO on their responses to deflection. The spike response rates of mechanosensory neurons of low-threshold hairs decreased when exposed to elevated NO levels caused by perfusion of the leg with saline containing the NO donor PAPANONOate. In contrast, in high-threshold hairs, which show low responsiveness under control conditions, an increase in spike rates was observed during PAPANONOate application. These opposing effects of NO reduce the differences in the spike responses of the two types of tactile hairs to mechanical stimulation and are likely to have an impact on behaviours elicited by mechanical stimulation of the legs.     

Sensilla and Cuticular Appendages on the Female Abdomen of Lasioptera rubi (Schrank) (Diptera,Cecidomyiidae)

Studies by SEM and TEM revealed 6 types of integumental appendages on female uromeres VIII-X in Lasioptera rubi: microtrichia, not innervated; spines, probably without sensory function; nonporous sensory hairs, each containing one dendrite ending with a tubular body indicating a tactile function; uniporous sensory hairs, each innervated partly by 3 dendrites indicating a chemosensory function, partly by an additional dendrite with a tubular body indicating a tactile function; scoop-like sensilla, each containing partly a branched structure of dendrites in the distal half of the sensillum indicating an olfactory function, partly an unbranched dendrite ending at a pore near the base of the sensillum, most probably registrating chemical stimuli by contact or gustation; finally, nonporous bristles, all or some of them innervated, in a manner indicating a tactile function. In addition, two scolopophorous proprioceptors were found inside uromere X. The nonporous sensory hairs, the uniporous sensory hairs and the scolopophores may be used by the midge to determine the mechanical and chemical properties of potential oviposition sites. The spines and nonporous bristles may function as conidia carriers.     

沟稃草属及其近缘属植物颖片微形态特征研究

通过扫描电镜对沟稃草属及其近缘属共14属20种2变种植物颖片微形态进行观察。结果显示:(1)沟稃草属颖片脉间长细胞长筒形或短筒形,细胞壁波状弯曲,显著增厚;脉间短细胞单生,脉间栓细胞近圆形,脉间硅细胞缺失;脉上硅细胞单生,近圆形,有气孔器,气孔副卫细胞平行形至低圆屋顶形;脉上、脉间刺毛常见,有钩毛,无微毛,有乳突,无大毛。(2)根据颖片微形态特征所构建的系统发育树显示,沟稃草属与早熟禾族植物聚为一支,表明其亲缘关系较近,支持将沟稃草属置于早熟禾族中。(3)沟稃草属与拂子茅属、野青茅属植物相距较远,颖片微形态证据不支持将沟稃草属作为广义拂子茅属的成员,其应该单独成属。     

The development of taste and tactile hairs in the pharate fly Protophormia terraenovae (Diptera,Calliphoridae) and in the embryonal cricket Acheta domestica (Orthopteroidea,Ensifera)

Summary 1. The development of taste hairs and tactile hairs of the fly Protophormia terraenovae is described using light microscope, scanning, and transmission electron microscope methods.2. The development of taste hairs proceeds in the same way on tarsi, labella, and wings. First the dendritic outer segments of ciliary origin become visible above the hypodermal cell surface [2 days after pupariation (AP) at 19° C]; then the dendritic sheath starts growing out and finally the trichogen process follows. In a typical intermediate stage (stage C) the distal sections of the dendrites float freely in the fluid surrounding the pharate adult. The more proximal sections are enclosed by the dendritic sheath around which the trichogen process is wrapped (4 days AP). The protruding dendrites disappear when the cuticle starts being deposited on the fully grown trichogen process, and the sheath vanishes later (9–10 days AP or 1 day before eclosion). The development is discussed with respect to the known structural organization of the adult hair.3. In the tactile hairs the single dendrite which grows outwards is completely covered by the dendritic sheath and lies beside the trichogen process [stage C(m)].4. The taste and tactile hair development proceeds in the same way on legs isolated from the pupa after disc eversion in an artificial medium containing ecdysterone.5. To check that both these patterns of development are widespread the development of taste and tactile hairs of the first instar cercus of the cricket Acheta domestica was studied with the light microscope: Both hair types pass through identical early stages.     

Radial expansion of root cells and elongation of root hairs of Arabidopsis thaliana induced by massive doses of gamma irradiation

Radial expansion of root cells and elongation of root hairs were induced within 3 d of a massive dose (3 kGy) of gamma irradiation to Arabidopsis thaliana. Because treatment with the antioxidant n-propyl gallate before irradiation suppressed these changes, gamma irradiation partially rescued the rhd2 mutant (defective in NADPH oxidase); the superoxide-generating reagent paraquat induced similar root morphogenesis. These responses appeared to be induced by the active oxygen species (AOS) generated by water radiolysis. Ethylene production was induced immediately after gamma irradiation and reached a steady level after about 2 h. Addition of the ethylene precursor 1-aminocyclopropane-1-carboxylic acid partly induced a similar expansion of root cells and elongation of root hairs. Addition of an inhibitor of ethylene biosynthesis, aminoethoxyvinylglycine, before gamma irradiation completely suppressed the formation of abnormal structures. These results suggest that the AOS is involved in the root morphological changes through the ethylene biosynthesis induced by gamma irradiation in Arabidopsis.     

Headspace measurements of irradiated in vitro cultured cells using PTR-MS

A pilot study was performed to evaluate a new concept for a radiation biodosimetry method. Proton transfer reaction-mass spectrometry (PTR-MS) was used to find out whether radiation induces changes in the composition of volatile organic compounds (VOCs) in the headspace of in vitro cultured cells. Two different cell lines, retinal pigment epithelium cells hTERT-RPE1 and lung epithelium cells A-549, were irradiated with gamma radiation at doses of 4 Gy and 8 Gy. For measuring the cell-specific effects, the VOC concentrations in the headspace of flasks containing cells plus medium, as well as of flasks containing pure medium were analyzed for changes before and after irradiation. No significant radiation-induced alterations in VOC concentrations in the headspace could be observed after irradiation.     

The functions of antennal mechanoreceptors and antennal joints in tactile discrimination of the honeybee (<Emphasis Type="Italic">Apis mellifera</Emphasis> L.)

Honeybees learn and discriminate excellently between different surface structures and different forms of objects, which they scan with their antennae. The sensory plate on the antennal tip plays a key role in the perception of mechanosensory and gustatory information. It is densely covered with small tactile hairs and carries a few large taste hairs. Both types of sensilla contain a mechanoreceptor, which is involved in the antennal scanning of an object. Our experiments test the roles of the mechanoreceptors on the antennal tip in tactile antennal learning and discrimination. Joints between head capsule and scapus and between scapus and pedicellus enable the bee to perform three-dimensional movements when they scan an object. The role of these joints in tactile antennal learning and discrimination is studied in separate experiments. The mechanoreceptors on the antennal tip were decisive for surface discrimination, but not for tactile acquisition or discrimination of shapes. When the scapus–pedicellus joint or the headcapsule–scapus joint was fixed on both antennae, tactile learning was still apparent but surface discrimination was abolished. Fixing both scapi to the head capsule reduced tactile acquisition.     

Electrical activity in the chemoreceptors of the blowfly. I. Responses to chemical and mechanical stimulation

The electrical responses of the neurons associated with the various types of chemosensory hairs of the blowfly, Phormia regina Meigen, following stimulation by chemical and mechanical means have been studied. The singly innervated chemosensory hairs on the ovipositor, maxillary palpi, and antennae respond vigorously to chemical stimulation, but not to mechanical stimulation. The triply innervated chemosensory hairs on the labellum, tarsus, and wing have two neurons which respond only to chemical stimuli. The third neuron responds only to mechanical stimulation. The differential responses of the two chemosensory neurons to various chemical stimuli following the removal of the tip of the hair suggest that the structures responsible for chemoreception are located throughout the distal processes of these neurons. The response of the third neuron to mechanical stimulation is similar to the response recorded from the neuron associated with one type of tactile hair which responds to motion and not to steady deformation. Recordings have been made from the neurons associated with purely tactile hairs using the cut hair as an extension of the micropipette. The mechanosensory neuron of the wing chemosensory hair is capable of responding at the rate of at least 600 impulses per sec. and may serve to indicate changes in air flow over the wing surfaces during flight to enable the fly to correct the wing camber and attack angle.     

Functional structure of the carpal and ventral vibrissae of the squirrel (Sciurus vulgaris)

A study is made of the histology, distribution and ultrastructure of nerve-organs in the carpal and ventral sinus hairs of the squirrel Sciurus vulgaris L. These sinus hairs were found to be typical tactile hairs. Their situation on the inner surfaces of the forelimbs, and on the ventral body wall is assumed to be useful during climbing. Five different types of nerve end-organs were found:
1. Ring-shaped end-organs, especially in the ring sinus, associated with certain cells in connectivetissue and in many cases also anchored to the hair follicle.
2. Merkelcells in the basal cell layer of the outer root sheath at the level of the ring sinus.
3. Lanceolate end-organs between the glassy membrane and the connective tissue of the ringwulst and betweenthese in the upper part of the ring sinus.
4. Encapsulated end-organs in the cavernous sinus.
5. Free thin nerveendings.