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1.
Summary. Rapid diffusion of allergenic proteins in isotonic media has been demonstrated for different pollen grains. Upon contact with stigmatic secretion or with the mucosa of sensitive individuals, pollen grains absorb water and release soluble low-molecular-weight proteins, these proteins enter in the secretory pathway in order to arrive at the cell surface. In this study we located allergenic proteins in mature and hydrated-activated pollen grains of Parietaria judaica L. (Urticaceae) and studied the diffusion of these proteins during the first 20 min of the hydration and activation processes. A combination of transmission electron microscopy and immunocytochemical methods was used to locate these proteins in mature pollen and in pollen grains after different periods of hydration and activation processes. Activated proteins reacting with antibodies in human serum from allergic patients were found in the cytoplasm, wall, and exudates from the pollen grains. The allergenic component of these pollen grains changes according to the pollen state; the presence of these proteins in the exine, the cytoplasm, and especially in the intine and in the material exuded from the pollen grains, is significant in the hydrated-activated studied times, whereas this presence is not significant in mature pollen grains. The rapid activation and release of allergenic proteins of P. judaica pollen appears to be the main cause of the allergenic activity of these pollen grains. Correspondence and reprints: Department of Plant Biology, Faculty of Biology, University of León, Campus de Vegazana, 24071 León, Spain.  相似文献   

2.
Pollinosis from Parietaria judaica is one of the main causes of allergy in the Mediterranean area. The present study is designed to assess if P. judaica pollens contain bioactive compounds able to elicit a functional response in endothelial cells.We have demonstrated that addition of pollen extract to human lung microvascular endothelial cells (HMVEC-L) induces a modification of cell morphology, actin cytoskeletal rearrangements and an increase in endothelial cell permeability. We further showed that the treatment of endothelial cells with pollen extract causes an increase of E-selectin and VCAM-1 protein levels as well as an increase of IL-8 production. The stimulation of cell-cell adhesion molecules was paralleled by a dose-dependent increase of adhesion of polymorphonuclear cells (PMNs) to HMVEC-L monolayer. Our results suggest for the first time that pollen affect directly endothelial cells (EC) modulating critical functions related to the inflammatory response.  相似文献   

3.
Summary The Juglans regia x Juglans nigra hybrid cannot be obtained because of stable interspecific barriers. We have analyzed and described various morphological and biochemical characters in J. regia and J. nigra pollen: differences in the mineral composition, polysaccharide reserves, wall ultrastructure and protein pattern of soluble cytoplasm, membranes, and cell-wall fractions. The absence of a glycoprotein fraction in the wall of J. nigra suggests that the regulation of critical steps in the interspecific matching with female tissues could be affected.  相似文献   

4.
Tulips: An Ornamental Crop in the Andalusian Middle Ages. The authors are working on the project “Crop Flora of al-Andalus,” which aims to recover the crop diversity of the Middle Ages in western Europe during the Islamic period. The documental sources of this study are all the agricultural treatises written in this territory and culture between the 10th and 14th centuries. Al-Andalus was the territory occupied by Islam between the 8th and 15th centuries, varying over time on varying regions on the Iberian Peninsula. In this period, a genuine agricultural revolution took place, as well as the incorporation into the Western world of many Eastern agricultural species. When we focused on the study of ornamental species used in gardens, courtyards, and houses, tulips could be identified in several texts, the main one being the ‘Umda, a botanical work written at the end of the 11th century or beginning of the 12th, probably by the agronomist Abu l-Jayr. Tulips are mentioned in this text 500 years before the first known references to their introduction into Europe, traditionally asserted to be from the Ottoman Empire to Holland via Austria, always in the 16th century. Thus the route of these ornamental bulbs in their passage from East to West must be modified.  相似文献   

5.
The study of sexual behavior has been largely utilized in phylogenetic analyses of Meloidae beetles. Sexual behavior of the tribe Cerocomini is almost unknown, even though the genus Cerocoma shows the most striking sexual dimorphism in the family. In this paper, the sexual behavior of five species, C. (Cerocoma) adamovichiana, C. (C.) graeca, C. (C.) schaefferi, C. (Metacerocoma) schreberi, and C. (M.) prevezaensis, is described. The cleaning behavior of this genus, previously unknown, is also discussed. A morphological analysis by scanning electron microscopy of sexually dimorphic anatomical features of antennae, maxillary palpi, and forelegs, involved in cleaning and sexual activities, is carried out.  相似文献   

6.
Fusariosis in the shrimp Penaeus semisulcatus cultured in Israel   总被引:1,自引:0,他引:1  
The first case of a mycotic infection in shrimp in Israel is reported. Fusarium solani produced a large melanized lesion in a specimen of Penaeus semisulcatus cultured at Eilat, on the Red Sea. Fungal hyphae elicited a strong hemocytic response in cuticular and connective tissues. In the underlying muscle, the inflammatory reaction appeared weaker, suggesting a gradual failure by the host to resist mycelial invasion. Three cases of human keratomycosis by F. solani have been reported in recent years in Israel, suggesting that handling infected shrimp may represent a hazard to aquaculturists.  相似文献   

7.
Summary We describe the use of scanning electron microscopy to provide novel views of the three-dimensional morphology of the ingrowth wall in epidermal transfer cells of cotyledons of developingVicia faba seed. Wall ingrowth deposition in these cells amplifies the surface area of plasma membrane available for transport of solutes during cotyledon development. Despite the physiological importance of such amplification, little is known about wall ingrowth morphology and deposition in transfer cells. A detailed morphological analysis of wall deposition in this study clearly established for the first time that wall ingrowths are deposited at scattered, discrete loci as papillate ingrowth projections. The new views of the ingrowth wall revealed that these projections branch and fuse laterally, and fusion occurs by fine connections to form a fenestrated sheet or layer. This sheet of wall material then provides a base for further deposition of ingrowth projections to progressively build many interconnected, fenestrated layers. Consolidation, or filling-in, of the fenestrae in these layers appears to occur from small fingerlike protrusions of wall material which extend laterally from the most recently deposited surface of the fenestrae. We propose that deposition of fenestrated layers may provide a mechanism for maintaining continuous amplification of plasma membrane surface area in the face of turnover of the plasma membrane and transporter proteins associated with it. The techniques reported in this paper will provide new opportunities to investigate wall ingrowth deposition and its regulation in transfer cells.Abbreviations SEM scanning electron microscopy - TEM transmission electron microscopy Dedicated to Professor Brian E. S. Gunning on the occasion of his 65th birthday  相似文献   

8.
Gerling  D.  Bar  D. 《BioControl》1985,30(4):409-414
BioControl - A 4 year study of the natural enemies attackingChrysoperla carnea (Stephens) in the cotton fields of Israel, revealed 4 parasite species,Tetrastichus sp.,Perilampus sp.,Helorus sp....  相似文献   

9.
Wheat (Triticum aestivum L.) and barley (Hordeum vulgare L.) stems in the Negev Desert of southern Israel are subject to mass infestations by stem sawflies larvae, primarily Trachelus tabidus F. (Cephidae, Hymenoptera). Infestations up to 55% and 50% in wheat and barley, respectively, were found in 1982/83. In addition, up to 8.6% of wild oat (Avena sp.) stems were cut by sawfly larvae in June 1983.The phenology of the insects was studied in 1981 to 1983 using yellow watertraps to catch adults and by dissecting infested stems to establish the pre-imaginal stages. Adults emerged at the end of February at magen and at the beginning of March at Gilat. Eggs and newly emerged larvae appeared in April. Larvae in diapause were found in cut stubs at the end of April and beginning of May. Pupae were found at the end of January and February.Of the sawfly specimens trapped in 1982 and 1983, the great majority was identified as T. tabidus and less than 5% as Cephus pygmaeus (Cephidae, Hymenoptera). The males of the sawflies appeared 4–6 days before the females, and were less numerous than them.About 12% of the larvae were parasitised by Tetrastichus sp. (Chalcidoidea, Eulophidae) in wheat, barley and wild oat, and about 4% by Collyria sp. (Ichneumoidea, Ichneumonidae) in wheat and barley stubs.
Résumé Les tiges de blé et d'orge subissent des attaques massives de tenthrèdes dans le désert du Négev au Sud d'Israël. Des attaques atteignant 55 et 50,4% ont été observée respectivement sur blé et orge en 1982/83.De plus, jusqu'à 8,6% de tiges d'avoine sauvage ont été coupées par les larves de tenthrèdes en juin 1983.La phénologie des insectes a été étudiée de 1981 à 83 en utilisant des pièges jaunes pleins d'eau pour capturer les adultes et en disséquant les tiges attaquées pour déterminer les stades préimaginaux.Les adultes ont émergé à fin de février et au début mars. Les oeufs et les larves sont apparus en avril. Les larves en diapause ont été trouvées dans les souches coupées à la fin de janvier et en février.La grande majorité de Cephidae adultes piégés en 1982 et 1983 a été identifiée Trachelus tabidus F., Cephus pygmaeus L. correspondait à moins de 5%. Les mâles de tenthrèdes sont apparus 4 à 6 jours avant les femelles qui étaient plus nombreuses.Environ 12% des larves étaient parasitées par un eulophide (Tetrastichus sp.) sur blé, orge et avoine sauvage, tandis que 3,6% l'étainent par un ichneumonide (Collyria sp.) dans les souches de blé et d'orge.
  相似文献   

10.
New observations on leaves of herbaceous lycopsid specimens previously attributed to Drepanophycus schopfii Mildenhall from Marie Byrd Land, West Antarctica, indicate that they belong to Haskinsia colophylla Grierson et Banks. Haskinsia was a wide spread lycopsid during the Middle Devonian.  相似文献   

11.
Fourteen species of Characeae were analyzed for their free amino acids. This study, in combination with previous results (Sakanoet al., 1984) showed that all the species that belong to the generaChara (6 species),Lamprothamnium (1 species),Nitellopsis (1 species),Lychnothammus (1 species) and 5Nitella species of the members of the subsectionAnarthrodactylae contained a large amount of isoasparagine. In contrast, no isoasparagine was found in the species belonging toTolypella (3 species) and otherNitella (7 species). Presence of isoasparagine in some species of Characeae (N. flexillis andNitellopsis obtusa) was found to be independent of their localities (Japan, Canada and England). Species lacking isoasparagine (N. oligogyra and N. axilliformis) did not produce isoasparagine even under the condition that induced a great increase of this amino acid in the species that contained it (C. corallina andN. flexilis). These results indicate that isoasparagine is a distinct taxonomic marker and suggest that theNitella species of the subsectionAnarthrodactylae are the most primitive group inNitelleae in that they share synthesis and accumulation of isoasparagine withChareae and, hence, support the view (Kasaki, 1964) that the subsection may be treated as an independent genus.  相似文献   

12.
Electrophoretic and morphological variation was studied in 13 cultivars ofC. lanatus and 31 accessions ofC. colocynthis from Israel. Twelve enzyme systems were assayed, representing 19 loci. We found 12 commercially grown cultivars to be monomorphic at all loci. OneC. lanatus accession collected from Israel is highly polymorphic and carries alleles ofC. colocynthis; this accession is probably a representative of a locally cultivated land race grown by Bedouins for animal feed. Over a range of 500 km two forms ofC. colocynthis were identified: one which grows along the coastal plains of the Mediterranean and the other in the arid Negev and Sinal deserts. A high level of electrophoretic and morphological divergence was found between plants of the two regions, whereas within the ecotypes little variation was observed.  相似文献   

13.
云南黄连为中药材黄连的原植物之一,为国家二级濒危保护植物。通过对云南黄连的开花物候、花部特征、繁育系统及传粉方式进行观察研究,以探讨云南黄连濒危机制,为其种质资源保护及人工抚育奠定基础。结果表明:(1)云南黄连的花期从12月份起至第二年的3月份,花期长达4个月,花序开花可持续45~60d,同一花序上不同花的开花时间相隔1~3d,单花花期可持续40~45d。(2)云南黄连为多歧聚伞花序,苞片包被花芽,花两性,雄蕊和心皮多数。(3)云南黄连的花粉-胚珠比(P/O)为9 000左右,杂交指数(OCI)值为4或5,为自交亲和但需要传粉者完成传粉的兼性异交型繁育系统,并存在无融合生殖现象。  相似文献   

14.
The non-acidic polygalacturonases produced by Aspergillus kawachii in a glucose/tryptone medium were adsorbed to a glass fiber microfilter that was used to clarify the fermentation broth. Maximum adsorption occurred at pH 3 under low ionic strength conditions. The adsorbed activity could be readily released with a buffer solution at pH 5. Based upon these observations, a separation process was developed which enabled the broth to be clarified and, at the same time, the non-acidic polygalacturonases to be concentrated 20-fold and purified 100-fold in a unique filtration step. The practical advantage of recovering polygalacturonases by a filtration process lies in the simplicity and efficiency of the operation involved. Received 27 July 2005; Revisions requested 24 August 2005; Revisions received 16 November 2005; Accepted 16 November 2005  相似文献   

15.
Calotropis procera (Asclepiadaceae) grows in Israel under extremely hot climatic conditions. Flower morphology is adapted towards the concealment of nectar, in order to protect it against robbery by ants and from evaporation. Pollinia while being inserted within the stigmatic chamber, are soaked in the liquid nectar which, by its concentration controls pollen germination. Two Carpenter bees (Xylocopa) are the only pollinators and their behavior on flowers is discussed.  相似文献   

16.
17.
Citrus rust mite, Phyllocoptruta oleivora (Ashmead), is a major pest of citrus in Israel. Five species of predatory mites: Amblyseius herbicolus Chant, Euseius victoriensis (Womersley), Euseius elinae (Schicha), Typhlodromus rickeri Chant and Euseius stipulatus (Athias-Henriot), were imported to improve the biological control of the pest. Mite rearing and sampling methods were developed and improved, and the predators were released. Recovery in some citrus orchards was recorded, but only E. victoriensis became established in the north of Israel.  相似文献   

18.
Robert E. Cleland 《Planta》1984,160(6):514-520
The relationship between the plastic-extensibility values (PEx) obtained in the Instron technique and the growth parameter, wall extensibility () has been evaluated for Avena sativa L. coleoptile cell walls. The possibility that PEx is proportional to the growth rate rather than to has been eliminated by showing that turgor-driven changes in the growth rate do not cause comparable changes in PEx. For Avena coleoptiles, PEx appears to be a measure of the average over the previous 60–90 min rather than a measure of the instantaneous of the growth equation. This is indicated by the fact that while PEx and the growth rate start to change simultaneously after addition of indole-3-acetic acid or KCN, the growth rate reaches a new, constant value 60–90 min before a new plateau value of PEx is obtained. Similar results are obrained with soybean (Glycine max L.) hypocotyl walls, indicating that the relationship between PEx and the parameter is a general one, although the period over which is averaged differs from tissue to tissue. In addition, it is shown that PEx can be measured more than once on the same section; a new potential for plastic extension is regenerated whenever the force vectors are changed even slightly. It is concluded that PEx is a measure of those domains in the wall where a wall-loosening event has occurred which has not been eliminated by further wall synthesis or other biochemical events.Abbreviations and symbols DP Instron plastic compliance - IAA indole-3-acetic acid - PEx Instron plastic extensibility - instantaneous wall extensibility  相似文献   

19.
20.
Outdoor tank cultivation of several Porphyra (nori) species was carried out from late November 2002 through early May 2003 using 40 L (with a surface of 0.25 m2), 600 L (1 m2), and 24,000 L (30 m2) fiberglass or PVC tanks provided with continuous aeration and seawater flow. Sexual and asexual spores produced from cultured conchocelis and frozen thalli in the laboratory, respectively, were subsequently grown to produce young fronds (ca. 5-10 cm) in an average time of 8 weeks. Growth in outdoor tanks and ponds was possible for a period of up to 20 weeks (i.e. growth season), with yields above 100 g FW m−2d−1occurring during 12-14 weeks from late December through late March, when seawater temperatures were below 20 C. These yields correlated with the species and depended on the type of tanks in which the algae were cultivated, with the highest yields observed for Porphyra sp. and Porphyra yezoensis when fertilized twice a week with NH4 Cl and NaH2 PO4in 40 L tanks. Calculations of productivity for an entire growth season based on ≥ 100 g FW m−2d−1yields exceed the average productivities using seeded nets in open sea, for all Porphyra species tested (0.96-4.06 kg DW m−2 season−1vs. 0.7-1.0 kg DW m−2of net season−1). Therefore, tank cultivation of Porphyra can offer an additional source of nori biomass to international markets. Land-based tank cultivation also offers an environmentally friendly practice that allows for the manipulation of growth conditions to enrich seaweeds with specific, valuable chemicals such as protein and minerals.  相似文献   

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