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中国叶螨属初步报道(蜱螨目:叶螨科) 总被引:1,自引:0,他引:1
叶螨属Tetranychus Dufour是极为重要的农业害虫,其中包括我国的著名大害虫棉叶螨(棉红蜘蛛)T.urticae和山楂叶螨(山楂红蜘蛛)T.viennensis,它们严重地为害棉花、果树、蔬菜等主要经济作物,与农业生产的关系至为密切。本文介绍了叶螨属的形态特征,报道了作者初步采集到的7种叶螨:1.棉叶螨(棉红蜘蛛)T.urticae;2.红叶螨T.telarius;3.山楂叶螨(山楂红蜘蛛)T.viennensis;4.牡荆叶螨T.viticis,新种;5.上海叶螨T.shanghaiensis,新种;6.野生叶螨T.desertorum,中国新记录;7.曼陀罗叶螨T.ludeni,中国新记录。最后,对棉叶螨和红叶螨的学名和中文名称的确定,进行了讨论。 相似文献
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<正> 叶螨总科(Tetranychoidea)包括了许多世界性分布的农业大害虫。研究叶螨的染色体,对于其分类、进化、性比和孤雌生殖等方面的研究均有十分重要的意义。叶螨个体小,染色体十分短小(一般1~4μm),给观察和研究带来了一定的难度。国外一般采用普通压片法制片、观察叶螨的染色体,但国内尚未见有关这方面的报道。作者以朱砂叶螨Tetranychuscinnabarinus(Boisduval)和二斑叶螨T.ur-ticae Koch为材料对叶螨染色体的制片技术进行了摸索,现简要报道如下。 相似文献
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智利小植绥螨饲养释放试验 总被引:4,自引:0,他引:4
<正> 柑桔全爪螨Panonychus citri(McGregor)是柑桔上的主要害虫之一。第二次世界大战后,由于长期使用有机磷等农药,引起了叶螨的猖獗为害,且其残毒及害虫的抗性已成为难以解决的问题。现在,害螨已成为棉花、小麦、果树及温室蔬菜上的大害虫。利用益螨防治害螨近年来的研究进展很快,引人瞩目的首推智利小植绥螨Phytosciulus persimilis Athias-Henriot,目前,北美、欧洲许多国家均已商品化,普遍用于防治温室内的叶螨及温室外棉花、土豆、瓜类、苹果、 相似文献
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害虫及害螨对阿维菌素抗药性研究进展 总被引:9,自引:0,他引:9
阿维菌素(avermectins)是一类新型高效广谱的生物源农药,对多种害虫及害螨具有极好的防效。随着阿维菌素在害虫及害螨防治中的广泛应用,害虫和害螨对其的抗性问题日益受到关注。文章综述国内外的最新研究结果表明:小菜蛾Pluttella xylostella(L.)、二斑叶螨Tetranychus urticate Koch等已对阿维菌素产生抗性,对阿维菌素产生抗性的害虫和螨并不总是表现适合度劣势,且抗性一旦产生敏感性较难以恢复;抗性遗传多数由多基因、不完全隐性控制;抗性机理涉及多种因素。综合分析发现害虫和螨对阿维菌素存在较大的、潜在抗性风险。 相似文献
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在室内条件下研究了圆果大赤螨对桑树害虫朱砂叶螨、桑蓟马和桑粉虱的捕食作用。结果表明,圆果大赤螨对3种猎物的捕食功能反应均符合HollingⅡ功能反应模型,经χ2检验,理论值与观测值差异不显著。捕食功能反应参数表明圆果大赤螨对桑蓟马、朱砂叶螨和桑粉虱捕食量差异显著,其最大日捕食量理论值分别为:416.67、222.22、97.09头。圆果大赤螨对猎物的搜寻效应均随猎物密度的增加而呈线性下降,且取食桑蓟马的搜寻效应明显高于朱砂叶螨和桑粉虱。HollingⅢ型功能反应新模型拟合得出,1头圆果大赤螨对桑蓟马、朱砂叶螨、桑粉虱的最佳寻找密度分别为77.54头、70.49头和27.27头。研究表明,圆果大赤螨对桑树害虫捕食能力依次为桑蓟马朱砂叶螨桑粉虱,且对3种害虫均具有较强捕食能力,是桑园害虫的重要天敌资源。 相似文献
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我国常见的两种异绒螨 总被引:1,自引:0,他引:1
<正> 异绒螨属Allothrombium隶于绒螨科(Trombidiidae),能捕食蚜虫和二斑叶螨等害虫,因此加强对异绒螨的研究对害虫综合治理有一定意义。我们在农田和果园中采到了一些异绒螨,并对其中一种进行了实验室饲养和野外观察。现将最常见的两种:红异绒螨和小枕异绒螨(新记录)记述如下,供有关实际工作者参考。 一、红异绒螨Allothrombium lerouxi Moss(图1) 相似文献
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二斑叶螨为害对菜豆生理指标的影响 总被引:1,自引:0,他引:1
二斑叶螨(Tetranychus urticae)是为害菜豆的重要害虫。本文研究了二斑叶螨不同密度和不同时间为害对菜豆各种生理指标的影响。结果表明:在二斑叶螨2头·叶-1的低密度和为害少于5 d的短时期内,菜豆叶片叶绿素a、叶绿素b和叶绿素总含量变化不大,但随着二斑叶螨为害时间的延长和密度的增大,叶绿素含量下降明显增加;总糖和还原糖的含量与二斑叶螨的为害程度关系密切,即为害时间越长、受害程度越严重,还原糖降低幅度越大,总糖的含量则先升高再降低;随着二斑叶螨为害程度的加重,菜豆叶片中全磷、全钾损失显著,全氮含量变化不显著。 相似文献
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苹果生长前期昆虫群落空间结构分析 总被引:13,自引:2,他引:11
在苹果生长的前期 ,将苹果树分为 1 8个区 ,研究每个区立体空间中的昆虫群落结构。结果分析表明 :苹果树中昆虫 (及螨类 )共有 2 7种 ,其中植食性害虫 1 5种 ,种数占总量的 5 5 5 6% ,天敌昆虫 1 2种占 44 44% ;昆虫群落在树上、下、中及内外层差异大 ,而在东、南、西、北 4方位上差异小。通过频次比较的方法与 χ2 检验得出 :梨星毛虫IlliberispruniDyar、山楂叶螨TetrangchusviennensisZacher、顶梢卷叶蛾SpilonotalechriaspisMeyrich均符合负二项分布 ;采用聚集指标法计算得出 :梨星毛虫、山楂叶螨、顶梢卷叶蛾均为聚集型分布 ,另外 ,山楂叶螨的I值最大 ,聚集度最高。以上的研究为苹果园有害生物综合治理提供理论依据 相似文献
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A new polynitro cage compound 2, 4, 6, 8, 10, 12, 13, 14, 15-nonanitro-2, 4, 6, 8, 10, 12, 13, 14, 15-nonaazaheptcyclo [5.5.1.1(3,11).1(5,9)] pentadecane (NNNAHP) was designed in the present work. Its molecular structure was optimized at the B3LYP/6-31 G(d,p) level of density functional theory (DFT) and crystal structure was predicted using the Compass and Dreiding force fields and refined by DFT GGA-RPBE method. The obtained crystal structure of NNNAHP belongs to the P-1 space group and the lattice parameters are a = 9.99 ?, b = 10.78 ?, c = 9.99 ?, α = 90.01°, β = 120.01°, γ = 90.00°, and Z = 2, respectively. Based on the optimized crystal structure, the band gap, density of state, thermodynamic properties, infrared spectrum, strain energy, detonation characteristics, and thermal stability were predicted. Calculation results show that NNNAHP has detonation properties close to those of CL-20 and is a high energy density compound with moderate stability. 相似文献
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Summary Concentration of N, P, K, Ca, Mg and S in summer groundnut crop was higher than in kharif while Zn, Fe, Mn and Cu contents were higher in summer crop. Kernel's N, P and Zn; Leaflet's Ca and Mn; Stem's K and Fe; Root's S and Cu and Petiole's Mg contents were highest. Shell's N, P, K, Mg, S, Zn and Cu; Kernel's Ca, Fe and Mn contents were the least. N, P, K, S, Zn and Cu concentrations decreased linearly as the crop grew. Ca, Mg, Fe and Mn concentrations did not display any distinct pattern. Ca concentration was positively correlated with pod yield in both the seasons. 相似文献
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The goal of this article was to establish reference ranges of the concentration of trace elements in human serum and to compare
these results with those reported by other authors. We describe the sample preparation and measurement conditions that allow
the rapid, precise, and accurate determination of Al, As, B, Be, Cd, Co, Cu, Fe, Li, Mn, Mo, Ni, Rb, Se, Sr, and Zn in human
serum samples (n=110) by inductively coupled plasma-mass spectrometry (ICP-MS). Accuracy and precision were determined by analyzing three
reconstituted reference serum samples by comparison with other methods and by the standard addition procedure.
The advantages of the ICP-MS method include short time of analysis of the elements mentioned, low detection limit, high precision,
and high accuracy. Disadventages include a high risk of contamination due to the presence of some of the elements of interest
in the environment, the relatively delicate sample handling, and the high cost of the equipment. 相似文献
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G. V. Iyengar 《Biological trace element research》1987,12(1):263-295
This report attempts to formulate reference ranges of elemental concentrations for 15 trace elements in selected human tissues
and body fluids.
A set of samples consisting of whole blood, blood serum, urine, milk, liver, and hair were chosen and considered for 15 elements
of biological significance: As, Cd, Co, Cr, Cu, F, Fe, I, Hg, Mn, Mo, Ni, Pb, Se, and Zn. The results represent wholly or
partially data received from 40 countries of the global regions of Africa, Asia, Europe, North, South, and Central America,
Australia, and New Zealand.
This survey, even if qualitative, has been useful in demonstrating certain trends of trace-element scenarios around the world.
It is of course recognized that both diet and environment exert a strong influence on the distribution pattern of several
elements, such as As, Cd, Mn, Pb, Se, and Zn. A limited comparison of the available information on soil status of different
countries reflected some interesting associations for elements, such as Mn and Zn.
Importantly, this study revealed that only a few countries were in a position to identify a reasonable amount of data on samples
requested for this project. Regretably, for a number of countries, any dependable data for even such essential elements as
Cu, Fe, and Zn were not available.
In view of the nutritional importance of many elements, the time is ripe for concerted efforts by intergovernmental agencies
to initiate investigations or commission task forces/projects to generate reliable reference data for selected global regions,
which sadly lack data of any kind at present. 相似文献
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The variation with age of the 18 trace element mass fractions and some histological characteristics of intact prostate glands of 50 subjects aged 0–30 years was investigated by instrumental neutron activation analysis, inductively coupled plasma atomic emission spectrometry, and a quantitative morphometric analysis. Mean values ± standard error of the mean (M ± SΕΜ) for the mass fractions (in milligrams per kilogram wet tissue) of these trace elements in pre-puberty were: Al 28.5 ± 9.0, B 0.40 ± 0.11, Ba 1.48 ± 0.44, Br 10.5 ± 1.5, Ca 241 ± 30, Cl 3,203 ± 278, Cu 3.51 ± 0.89, Fe 33.7 ± 4.1, K 2,364 ± 145, Li 0.020 ± 0.004, Mg 153 ± 23, Mn 0.46 ± 0.06, Na 2,286 ± 130, P 1,391 ± 100, S 1,698 ± 132, Si 62 ± 11, Sr 0.38 ± 0.08, and Zn 27.6 ± 2.3. During puberty and postpuberty, when there is a significant increase in circulating androgens, the mean values were: Al 7.2 ± 1.4, B 0.21 ± 0.05, Ba 0.25 ± 0.06, Br 5.8 ± 1.0, Ca 433 ± 81, Cl 2,314 ± 201, Cu 1.77 ± 0.13, Fe 20.9 ± 1.6, K 2,585 ± 118, Li 0.0088 ± 0.0014, Mg 232 ± 27, Mn 0.34 ± 0.04, Na 1,875 ± 107, P 1,403 ± 98, S 1,673 ± 73, Si 22.2 ± 3.1, Sr 0.22 ± 0.03, and Zn 93.3 ± 8.9. Mean values (M ± SΕΜ) of percent volumes (%) of the stroma, epithelium and lumen in the prostate before puberty were 73.4 ± 2.6, 20.4 ± 1.7, and 4.45 ± 0.94, respectively, versus 46.5 ± 2.5, 38.5 ± 1.9, and 14.9 ± 1.2 during puberty and postpuberty. This work’s results confirm that the Zn mass fraction in prostate tissue is an androgen-dependent parameter. For the first time it has been demonstrated that the glandular lumen is a main pool of Ca, Mg, and Zn accumulation and that the stroma is a main pool of Al, B, Ba, Br, Cl, Cu, Fe, Mn, Na, and Si accumulation in the normal human prostate, for the age range 0–30 years. It was concluded that the Ca, Mg, and Zn binds tightly within the prostatic fluid, because the volume of glandular lumen reflects the volume of prostatic fluid. 相似文献
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Vladimir Zaichick Sofia Zaichick Vasilii Karandashev Sergey Nosenko 《Biological trace element research》2009,129(1-3):107-115
The effect of age and gender on major, minor, and trace element contents in the intact rib bone of 80 relatively healthy 15–55-year-old women and men was investigated. Contents or upper limit of contents of 16 chemical elements in the rib bone were determined by inductively coupled plasma atomic emission spectrometry (ICP-AES). Mean values (M?±?SΕΜ) for the mass fraction of Ba, Ca, Cu, Fe, K, Li, Mg, Na, P, S, Sr, and Zn (milligram per kilogram of dry bone) were as follows: 2.54?±?0.16, 171,400?±?4,050, 1.35?±?0.22, 140?±?11, 1,874?±?71, 0.049?±?0.011, 2,139?±?38, 5,378?±?88, 75,140?±?1,660, 1,881?±?51, 291?±?20, and 92.8?±?1.5, respectively. The upper limits of contents of Al, B, Mn, and V were <7.20, <0.65, <0.36, and <0.03, respectively. Statistically significant tendency for the Ca, Mg, and P content to decrease with age was found in the human rib bone, regardless of gender. The mass fraction of Fe in the male rib bone increases with age. It was shown that higher Ca, Mg, Na, P, and Sr mass fractions as well as lower Fe content were typical of female ribs as compared to those in male ribs. 相似文献
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Oral cancer is one of the main causes of cancer-related deaths in South-Asian countries. There are very limited treatment options available for oral cancer. Research endeavors focused on discovery and development of novel therapies for oral cancer, is necessary to control the ever rising oral cancer related mortalities. We mined the large pool of compounds from the publicly available compound databases, to identify potential therapeutic compounds for oral cancer. Over 84 million compounds were screened for the possible anti-cancer activity by custom build SVM classifier. The molecular targets of the predicted anti-cancer compounds were mined from reliable sources like experimental bioassays studies associated with the compound, and from protein-compound interaction databases. Therapeutic compounds from DrugBank, and a list of natural anti-cancer compounds derived from literature mining of published studies, were used for building partial least squares regression model. The regression model thus built, was used for the estimation of oral cancer specific weights based on the molecular targets. These weights were used to compute scores for screening the predicted anti-cancer compounds for their potential to treat oral cancer. The list of potential compounds was annotated with corresponding physicochemical properties, cancer specific bioactivity evidences, and literature evidences. In all, 288 compounds with the potential to treat oral cancer were identified in the current study. The majority of the compounds in this list are natural products, which are well-tolerated and have minimal side-effects compared to the synthetic counterparts. Some of the potential therapeutic compounds identified in the current study are resveratrol, nimbolide, lovastatin, bortezomib, vorinostat, berberine, pterostilbene, deguelin, andrographolide, and colchicine. 相似文献