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Juniperus deltoides R.P.Adams is a prickly, evergreen shrub that grows in the East Mediterranean on dry hills and mountains. Needle-like leaves have a thick cuticular layer on the surface, which serves as the ultimate barrier for prevention of water loss. n-Alkanes comprise the biggest part of this hydrophobic wax mixture. These compounds are studied as chemophenetic characters due to their chemical and physiological stability, and strong genetic control. Six central Balkan populations were studied and compared to one eastern and one western. Fifteen n-alkanes were identified, with C33 being dominant in all samples. Univariate and multivariate statistical analyses separated western population from all central Balkan populations, while the eastern Balkan population showed high similarity with the central ones. Climatic, orographic and pedological characteristics of the studied localities were also taken into account.  相似文献   

3.
通过对我国不同地区繁育的白蜡虫泌蜡实验,表明云南、四川、贵州三省白蜡虫泌蜡量多,其它省区的白蜡虫泌蜡量少。据此建议生产部门在以上三省大力提倡发展白蜡虫生产。  相似文献   

4.
Utilizing freeze-fracturing and conventional electron microscopy methods, we have studied the details of morphogenesis and construction of the wax layer envelope from Oregon R and mutants of Drosophila melanogaster egg' s during oogenesis. The wax layer is synthesized and secreted by the follicular cells in the 10b of lipid vesicles during static 10b. During secretion (stages 10b, 11 and 12) the lipid vcsicles are accumulated on the vitelline membrane surface and become flat. At the late stage of choriogenisis (stages 13, 14) the lipid vesicles are compressed tightly between the vitelline membrane and the other already constructed eggshell layers, so the wax layer becomes very thin and is hardly seen in crossfractured views.  相似文献   

5.
为明确小麦不同器官表皮蜡质晶体结构和蜡质组分的差异,该研究以小麦品系CP98(11)为材料,在小麦扬花期分别取小麦的旗叶、叶鞘、穗下茎、花药和颖壳,利用气相色谱技术对各器官表皮蜡质组分进行鉴定,并通过扫描电镜观察其蜡质晶体结构。结果表明:(1)小麦不同器官的蜡质成分共鉴定出30种,主要为初级醇、二酮、烷烃、脂肪醛、脂肪酸、酯。(2)叶鞘、穗下茎、颖壳的蜡质中二酮含量最高,分别占蜡质总量的78.96%、67.03%和68.6%;花药的蜡质中烷烃含量最高(75.82%);旗叶的蜡质中初级醇含量最高(45.91%),其次为烷烃33.19%。(3)扫描电镜观察显示,旗叶正面的蜡质晶体呈片状结构,旗叶反面和颖壳的蜡质晶体结构呈片状与柱状混合的结构,花药的蜡质呈明显的波浪状结构,穗下茎和叶鞘的蜡质晶体呈柱状结构。  相似文献   

6.
植物蜡质及其与环境的关系   总被引:8,自引:0,他引:8  
陆生植物的地上部分如叶、茎、花、果实等的表面覆盖着一层蜡质,它是由一系列复杂化合物组成的具有三维微结构的疏水层,在植物生长和发育过程中起着不可或缺的作用,具有很好的生物学功能。作为植物与环境的第一接触面,蜡质对外界环境因子的响应较敏感,当植物受到外界不利环境因子胁迫时,蜡质会改变自身晶体结构形态或化学组分构建防御机制以减少胁迫因子的作用,有效地协调植物与环境的关系。综述了近年来国内外关于植物蜡质的研究进展,在阐述蜡质层结构及其化学组分的基础上,着重介绍植物与环境因子的作用,包括非生物环境因子如水分、温度、光照、环境污染等以及植食性昆虫和病原菌等生物环境因子的作用。研究显示,胁迫环境下植物蜡质化学组分的变化,是由于不利环境因子的作用足以改变蜡质各产物的合成途径,从而影响蜡质产物。植物蜡质利用各种生理、化学机制对胁迫环境因子的适应以及响应,是植物适应各种生境的基础,因此通过对植物蜡质与环境关系的研究为进一步解析植物与环境关系提供证据。  相似文献   

7.
Vaginal candidiasis characterized by abnormal vaginal discharge and itching usually treated by azole’s drug or nystatin; however, some results of treatment are unsatisfied and become recurrent. Propolis containing polyphenols and flavonoids is known to have anti-inflammatory and antimicrobial activity. This study investigated the effect of Indonesian propolis wax from Tetragonula sp. as a therapy in limited vaginal candidiasis patients. The subjects were women who came to the Tasik Community Health Centre met the inclusion criteria such as clinical complaint and laboratory evaluation (positive hyphae/pseudohyphae and culture on Sabouraud Dextrose Agar (SDA) medium) from a vaginal swab. Evaluation of anti-candida effect of propolis was determined by clinical remission and the absence of Candida’s growth on SDA medium. Forty subjects were randomly assigned to those receiving treatment by ovule propolis (n = 20) and that treatment by nystatin (n = 20) as a control, once daily, for seven days, respectively. All methods have been approved by the Ethics Commission of the Faculty of Medicine, Universitas Indonesia. Our results indicated no significant difference in the laboratory evaluation of patients who have treated ovule propolis compared to standard therapy. This study suggests that propolis wax has a beneficial effect to develop as an anti-candida agent for vaginal candidiasis therapy.  相似文献   

8.
Naturally occurring macromolecules present at the epicuticular wax/stalk tissue interface of sugarcane were investigated using near infrared spectroscopy (NIRS). Investigations of water, cellulose, and wax‐cellulose interrelationships were possible using NIRS methods, where in the past many different techniques have been required. The sugarcane complex interface was used as an example of typical phenomena found at plant leaf/stalk interfaces. This detailed study showed that sugarcane cultivars exhibit spectral differences in the CHn, water OH, and cellulose OH regions, reflecting the presence of epicuticular wax, epidermis, and ground tissue. Spectrally complex water bands (5276 cm?1 and 7500–6000 cm?1) were investigated via freeze‐drying experiments which revealed sequentially a complex band substructure (7500–6000 cm?1), a developing weak H‐bonding system (~7301 cm?1), and strong H‐bonding (~7062 cm?1) assigned to water—cellulose interactions. Principal component analysis techniques clarified complex band trends that developed during the desorption experiment. Bands from wax‐free stalk were minimized in the 4327–4080 cm?1 region (C? Hn vibrational modes associated with long chain fatty compounds), while bands from the stalk tissue (particularly lignin and moisture) became more pronounced. This work is a comprehensive guide to similar studies by scientists involved in a variety of plant and fiber research fields. © 2009 Wiley Periodicals, Inc. Biopolymers 91: 642–651, 2009. This article was originally published online as an accepted preprint. The “Published Online” date corresponds to the preprint version. You can request a copy of the preprint by emailing the Biopolymers editorial office at biopolymers@wiley.com  相似文献   

9.
Sedum album is a succulent plant, with phenotypic variability resulting in delimitation of a number of taxa with diverse taxonomic recognition. We analyzed the taxa from Sedum album in broad sense (S. album, S. micranthum, S. athoum and S. serpentini) from Balkan Peninsula, to check whether the variability of their epidermal structures and epicuticular wax composition corresponds to their taxonomic reliability. Epidermal structures and epicuticular waxes were analyzed using light and scanning electron microscopy, gas chromatography-mass spectrometry and gas chromatography-flame ionization detector chromatography and multivariate statistical techniques. Analyses of studied taxa have shown that significant systematic characters include adaxial epidermal and guard cell length, stomatal frequency and subsidiary cells area on abaxial epidermis. The content of n-alkanes C29, C30, C27, C32 and C33 was shown to be valuable criterion for their phytochemical delimitation. The comparison of epicuticular wax microstructures has shown no significant differences. Results indicate presence of two (micromorphology) or three (phytochemistry) well-defined groups of populations, with S. serpentini manifesting a considerable level of separation toward the others. Sedum athoum have shown weak to moderate degree of differentiation, while S. micranthum has shown general resemblance to S. album.  相似文献   

10.
白蜡虫几个地方种虫经济性状的比较研究   总被引:4,自引:0,他引:4  
本文对四川省几个地方种虫的虫囊含卵量、性比、虫囊大小分配情况、100粒虫囊重量、泌蜡期及泌蜡量等经济性状作了比较研究。  相似文献   

11.
植物角质层蜡质的化学组成研究综述   总被引:5,自引:0,他引:5  
曾琼  刘德春  刘勇 《生态学报》2013,33(17):5133-5140
角质层是植物与外界的第一接触面,而角质层蜡质则是由位于角质层外的外层蜡质和深嵌在角质层中的内层蜡质两部分构成。植物角质层蜡质成分极其复杂,具有重要的生理功能。综述了有关植物角质层蜡质的化学组成信息,探讨了目前植物角质层蜡质化学成分研究中存在的一些问题,展望了角质层蜡质成分的研究前景。  相似文献   

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13.
The present study was carried out to investigate the degree of leaf wetness and its capacity to retain water droplets in relation to leaf morphological characteristics of Valeriana jatamansi J. grown under open and shade habitats. Leaves developed in open habitats had less wettability but higher capacity to retain water droplets and more number of stomata than shade leaves. A significant positive correlation of contact angle () were noticed with trichome length, droplet retention and wax content.  相似文献   

14.
We investigated the interaction of elevated CO2 and/or (Ozone) O3 on the occurrence and severity of aspen leaf rust (Melampsora medusae Thuem. f. sp. tremuloidae) on trembling aspen (Populus tremuloides Michx.). Furthermore, we examined the role of changes in leaf surface properties induced by elevated CO2 and/or O3 in this host–pathogen interaction. Three‐ to five‐fold increases in levels of rust infection index were found in 2 consecutive years following growing‐season‐long exposures with either O3 alone or CO2 + O3 depending on aspen clone. Examination of leaf surface properties (wax appearance, wax amount, wax chemical composition, leaf surface and wettability) suggested significant effects by O3 and CO2 + O3. We conclude that elevated O3 is altering aspen leaf surfaces in such a way that it is likely predisposing the plants to increased infection by aspen leaf rust.  相似文献   

15.
Lymphoid tissue, and/or isolated peripheral mononuclear blood cells were fixed in acid ethanol and embedded in polyester wax (melting point 37 C). The excellent cytomorphol-ogy obtained allowed distinguishing different types of individual lymphoid and nonlymphoid cells. Furthermore, this procedure was satisfactory in the immunophenotyping of histiocytes, endothelial, mesenchymal, epithelial cells, different (sub-) types of lymphocytes and also of lym-phokine activated killer (LAK) cells. The staining patterns obtained with the different poly- and monoclonal antibodies on polyester wax sections were not only analogous to those obtained on frozen sections, but cells which had incorporated bromodeoxyuridine could be double labeled with specific antiserum.  相似文献   

16.
The epicuticular waxes of the two sorghum varieties Alliance A and SD 102 have been analyzed, after separation of the leaf blades from the sheaths. The major constituents were found to be free fatty acids but small amounts of esters, aldehydes, alcohols, n-alkanes and sterols were also detected. The typical chain lengths of aldehydes, free alcohols and free fatty acids were C28 and C30.  相似文献   

17.
The phase behaviour of cuticular waxes from leaves of Hedera helix L. and Juglans regia L. was studied by Fourier transform infrared spectroscopy. For this purpose reconstituted waxes, isolated cuticular membranes, dewaxed polymer matrix membranes and whole leaves were studied in the horizontal attenuated total reflection and transmission modes. Melting curves of cuticular waxes were derived from temperature-dependent changes in the absorption maximum of the symmetric stretching mode of CH2 groups (νs, at approx. 2856–2848 cm−1). With increasing temperature absorption band doublets due to CH2 scissoring (δsciss) and rocking (δrock) movements (at approx. 1473–1471 and 730–720 cm−1, respectively) indicative of an orthorhombic arrangement of alkyl chains merged into a single peak. The area ratio of the peaks at approx. 720 and 730 cm−1 was used as a measure for aliphatic crystallinity of plant cuticular waxes at a given temperature. The investigations of reconstituted cuticular waxes and those still embedded in isolated cuticles or in situ on the leaf produced comparable results. The findings are discussed in terms of the properties of the cuticular transport barrier. Received: 21 March 1997 / Accepted: 25 April 1997  相似文献   

18.
Paraffin sections are usually rehydrated before staining. It is possible to apply aqueous dye solutions without first removing the wax. Staining then occurs more slowly, and only if the embedding medium has not melted or become unduly soft after catting. To avoid this problem, sections are flattened on water no hotter than 45 C and dried overnight at 40 C. Minor technical modifications to the staining procedures are needed. Mercury deposits are removed by iodine, and a 3% solution of sodium thiosnlfate in 60% ethanol is used to remove the iodine from paraffin sections. At room temperature, progressive staining takes 10–20 tunes longer for sections in paraffin than for hydrated sections; at 45 C, this can be shortened to about three times the regular staining time. After staining, the slides are rinsed in water, air dried, dewaxed with xylene, and coverslipped in the usual way. Nuclear staining in the presence of wax was achieved with toluidine blue, O, alum-hematoxylin and Weigert's iron-hematoxylin. Eosin and van Gieson's picric acid-acid fuchsine were effective anionic counterstains. A one-step trichrome mixture containing 3 anionic dyes and phosphomolybdic acid was unsuitable for sections in wax because it Imparted colors that were nninformative and quite different from those obtained with hydrated sections. Advantages of staining in the presence of wax include economy of solvents, reduced risk of overstaining and strong adhesion of sections to slides.  相似文献   

19.
Infection of Galleria mellonella larvae with five spiroplasma strains caused increased mortality and decreased growth rates of larvae. Reductions in growth rate and survival were related to spiroplasma strain and multiplication rate of the spiroplasma in the larvae. Three strains, considered to be ephiphytic on flowers (23-6, SR-3, PPS1), proved highly pathogenic to G. mellonella larvae, whereas strains known to be pathogenic to plants (SC-27) or honeybees (G-1) had a lesser impact.  相似文献   

20.
Intraspecific variation in four New Zealand species of Chionochloa, C. flavescens, C. pallens, C. rigida; and C. rubra, was investigated by examining the major carbon chain lengths of fatty acids, alcohols, aldehydes, wax esters and alkanes of the epicuticular waxes. The major even-carbon chain lengths ranged generally from C24 to C32 in the acids, alcohols and aldehydes; C29 to C33 in the alkanes; and even-carbon chains between C36 and C52 in the wax esters. A computer program was used to calculate the degree of similarity between samples in terms of chain length distribution. In C. rigida eastern and western South Island localities were identified; in C. flavescens Canterbury and Nelson, western South Island and southern North Island regions were recognized; and C. pallens and C. rubra were divisible into four regions; Canterbury, Nelson, western South Island and southern North Island. The possible elongation-decarboxylation pathways and the specificity of the enzymes in the biosynthetic pathways of epicuticular wax synthesis suggest the possibility that the northwest Nelson region could be a biogenetic centre from which wax synthesis has diversified along three routes, one to the western South Island, another to eastern South Island and the third to southern North Island. Identification of each of the four species based on the distribution of the carbon chain lengths in the individual lipid fractions is impossible unless the locality of collection is known. Intraspecific variation in lipid composition is not coincident with patterns of variation already reported.  相似文献   

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