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本文对甜菜夜蛾核型多角体病毒的两个分离株(SeMNPV-M,SeMNPV-Z)的生物活性进行了比较,并对甜菜夜蛾核多角体病毒杀虫悬浮剂的田间应用效果进行了评估.病毒生物测定结果显示,SeNPV-M和SeNPV-Z感染三龄幼虫的半致死剂量(LD50)分别为195.8 PIBs/克饲料和242.4 PIBs/克饲料.使用6000PIB/克饲料的病毒剂量感染三龄幼虫,其半致死时间(LT50)分别为3.50d和3.68d.甜菜夜蛾病毒杀虫悬浮剂已在工厂生产,田问实验结果表明,甜菜夜蛾病毒杀虫悬浮剂可有效控制目标害虫的危害. 相似文献
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本文报道了甜菜夜蛾核型多角体病毒 (Spodopteraexiguanuclearpolyhedresisvirus,SeN PV)美国分离株的形态学观察、宿主范围的测定、活体生物测定及其与甜菜夜蛾核型多角体病毒中山大学分离株的毒力、限制性内切酶图谱比较等研究结果。以喂饲法用SeNPV美国分离株感染 4龄初甜菜夜蛾幼虫 ,收集具典型病症的虫尸并提纯多角体。取纯多角体进行包埋、切片。电镜观察表明 ,此甜菜夜蛾NPV为多粒包埋型核型多角体病毒。用SeNPV美国分离株以 1 .3× 1 0 7PIBs/mL分别感染甜菜夜蛾… 相似文献
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银纹夜蛾幼虫 (Argyrogrammaagnata)对松毛虫CPV(DpCPV)十分敏感 ,本文对两种不同的宿主增殖松毛虫CPV作了比较 ,电镜证实用替代宿主增殖的DpCPV与原毒株多角体 (CPB)和病毒粒子的形态完全一致。 3 %PAGE分析二者的RNA图谱基本一致 ,有大小相同的 2 .98× 10 6- 0 .6 6× 10 6道尔顿的 10条带 ,用它增殖的DpCPV(Aa DpCPV)对松毛虫有相当的毒力 ,每头 3龄幼虫病毒产量平均为 2 .5× 10 8CPB。 相似文献
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本文对甜菜夜蛾核型多角体病毒的两个分离株(SeMNPV-M,SeMNPV-Z)的生物活性进行了比较,并对甜 菜夜蛾核多角体病毒杀虫悬浮剂的田间应用效果进行了评估。病毒生物测定结果显示,SeNPV-M和SeNPV-Z 感染三龄幼虫的半致死剂量(LD50)分别为195.8 PIBs/克饲料和242.4 PIBs/克饲料。使用6000PIB/克饲料的病 毒剂量感染三龄幼虫,其半致死时间(LT50)分别为3.50d和3.68d。甜菜夜蛾病毒杀虫悬浮剂已在工厂生产,田间 实验结果表明,甜菜夜蛾病毒杀虫悬浮剂可有效控制目标害虫的危害。 相似文献
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寄主卵龄和接触时间对夜蛾黑卵蜂寄生能力的影响 总被引:1,自引:0,他引:1
在温度(26±1)℃、RH70%±5%、光暗比L:D=12:12的条件下,研究了在接触时间为6、12、24、36h情况下,夜蛾黑卵蜂Telenomus remus Nixon对卵龄为0、6、12、24、36h的甜菜夜蛾Spodoptera exigua(Hübner)第1天和第2天所产卵的寄生率、子代羽化率和性比。结果表明,夜蛾黑卵蜂寄生第1天卵龄为6h的寄主卵24h后,寄生率、子代羽化率和性比显著高于其他条件,分别为56.97%、89.11%和87.63%;寄生第2天相同条件的卵,寄生率、子代羽化率和性比也显著高于其他条件,分别为54.47%、95.37%和88.72%;寄生第1天和第2天的卵,其寄生率和子代性比差异不显著,但寄生第2天卵的子代羽化率显著高于寄生第1天卵的子代羽化率。因此,在室内以甜菜夜蛾为寄主繁育夜蛾黑卵蜂,最好以甜菜夜蛾第2天卵龄为6h的卵为寄主,接触时间以24h最适。该结果对夜蛾黑卵蜂应用于田间防治甜菜夜蛾具有指导意义。 相似文献
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为了弄清楚莱氏野村菌田间自然发生流行规律,本研究于2012-2014年对云南省昆明市晋宁区花椰菜上莱氏野村菌的发生动态进行了调查研究,发现莱氏野村菌能感染银纹夜蛾Argyrogramma agnata和甜菜夜蛾Spodoptera exigua幼虫,二者的田间被感染症状相似。在昆明市晋宁区花椰菜田间,莱氏野村菌于每年7-10月份在银纹夜蛾和甜菜夜蛾幼虫种群中发生流行,其中9月份为发生流行高峰期,而银纹夜蛾幼虫的田间自然感染率高于甜菜夜蛾。2012-2014年7月、8月、9月、10月银纹夜蛾的平均感染率分别为34. 38%、62. 53%、78. 49%和33. 67%,甜菜夜蛾的平均感染率分别为8. 39%、8. 65%、24. 49%和3. 47%。该菌对同种害虫不同龄期幼虫的感染率不同,其中银纹夜蛾1-3龄幼虫的感染率高于4-5龄;而甜菜夜蛾4-5龄幼虫的感染率高于1-3龄。该研究将为莱氏野村菌开发利用及银纹夜蛾和甜菜夜蛾的生物防治研究提供依据。 相似文献
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苏云金芽孢杆菌 (Bacillusthuringiensis,Bt)WY 197菌株是从 4 0 0多株野生型Bt菌中筛选分离的1株对甜菜夜蛾和棉铃虫都具有高效杀虫活性的菌株。初步比较WY -197菌株和HD 1的形态特征、生理生化特性和伴孢晶体蛋白 ,结果表明 ,WY -197属于H3a3b3c血清型 (subsp .kurstaki) ;伴孢晶体形态主要为大小不一的菱形、小正方形。SDS -PAGE电泳图谱表明主要由 135ku和 6 5ku两种蛋白成分组成 ,在菌株生长形态、发酵培养特征、生理生化特性方面与生产菌株HD-1差别不大。采用生物测定的方法 ,进一步鉴定比较它们对甜菜夜蛾初孵、二龄、三龄幼虫和棉铃虫的毒效差异。结果表明 ,BtWY 197菌株发酵液对甜菜夜蛾初孵、二龄、三龄幼虫的LC50 分别为 0 .31、0 .6 1、2 .5 7μL/mL ,其中对甜菜夜蛾初孵幼虫的毒效是对照菌HD 1发酵液的 7倍 ,表明BtWY 197菌株对甜菜夜蛾三龄以下幼虫具有高毒力。对棉铃虫的毒力效价为 30 0 0IU/ μL ,略低于HD- 1菌株。 相似文献
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本研究工作中,建立了一个有效的甜菜坏死黄脉病毒的分离提纯程序,解决了该病毒粒体易于聚集难以提纯的问题,其操作要点是,(1)通过Sepharose 2B柱层析代替超离心,有效地除去一些小分子量核酸杂质;(2)经PEG再次沉淀浓缩后,调整pH至酸牲(pH3.0),使病毒充分悬浮以减少凝聚;(3)在病毒等电点(pH4.8~4.9)条件下,进一步沉淀以纯化病毒。根据病毒提取物的OD260/OD280比值,算出核酸含量约4.5%。核酸电泳出现4条带,分子量分别为:2.25×10~(?),1.8×10~(?),1.05×10~(?),0.75×10~(?)道尔顿。病毒提取物经超速离心出现4个界面,沉淀系数分别为,200.8S,165S,125.8S,100S。说明甜菜坏死黄脉病毒可能是4组分病毒粒体。病毒粒体含一蛋白亚基,分子量约为2.05±0.05×10~4道尔顿,由16种共199个氨基酸组成。 相似文献
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甜菜夜蛾抗寒与越冬能力研究 总被引:28,自引:2,他引:28
研究了甜菜夜蛾不同虫态的过冷却点、耐低温能力、可能的越冬虫态及其越冬能力,并结合气象资料的分析,初步确定了我国甜菜夜蛾的越冬北界.甜菜夜蛾3~5龄幼虫的过冷却点较高,分别为-11.17℃、-11.96℃和-10.50℃(平均-11.21℃),预蛹期次之,为-12.47℃,蛹期最低,平均为-17.16℃.在5℃、0℃、-10℃和-5℃条件下,甜菜夜蛾各种虫态的LT50、LT90和LT99.9均随温度的降低而缩短,尽管不同虫态的耐低温能力有很大的差别.其耐低温能力由弱至强的排列顺序依次为卵<成虫<幼虫<蛹.这些结果表明,蛹是甜菜夜蛾的四个虫态中耐低温能力最强的,因而是最可能的越冬虫态.但由于蛹在0℃条件下的LT99.9为38.06d,表明甜菜夜蛾在冬季0℃以下的温度超过38d的地区不能越冬.另外,连续两年冬春的田间试验结果表明,蛹在北京西郊越冬死亡率均为100%,说明甜菜夜蛾在北京地区不能越冬.根据这些结果并结合我国气温的变化规律,初步将我国甜菜夜蛾的越冬北界定于北纬38°左右,即1月份-4℃等温线左右. 相似文献
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The aim of this report has been to present results concerning analytical quality controls of Hg analysis of fish and sediment, analyses of Fe, Ca, total-P, K, pH, alkalinity, conductivity, colour and hardness (Ca + Mg) of lake water samples. Despite the fact that these are standard parameters in many regular water control programs, there are major differences in the reliability with which these parameters can be determined. The focus here is on an overall inter-laboratory comparison between the parameters. Six laboratories have been involved in the analysis. Selected results: pH gives the lowest (average) relative standard deviation (error), about 2 %; conductivity gives an error of about 5–7 %; alkalinity yields an average error of as much as 13–25 %, which is the largest among the parameters studied here; colour also gives a high error, 9–15 %; hardness gives a relative standard deviation of about 6–7 %. Of the other parameters (i. e., Hg, Fe, Ca and P), Hg gives the best reliability and Fe and P the lowest. To have knowledge of the reliability of the analytical data is of paramount importance in most control programs and research projects. 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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K Dolowy 《Journal of theoretical biology》1975,52(1):83-97
The cell has been represented as a charged liquid drop. Contrary to the DLVO-theory, the effect of the surface potential upon the value of the interfacial tension of the cell membrane has also been taken into consideration. The cell membrane has visco-elastic properties and its constituents may move against each other. Cell movement is caused by the appearance of a small number of the electrically charged constituents of the cell membrane on the leading edge of the cell. This produces a local decrease in the surface tension and the cell membrane expansion. At the moment of contact between two cells proton transfers occur between the strongly negatively charged microvilli of one cell and the body of the other, analogous to a condenser breakdown. This, through the effect on the surface tension, causes contact inhibition of movement. The distribution of the proton dissociable groups modifies the interaction between the cells (differentiation) and between the cell and the substratum (adhesion). Adsorption of the charged compounds at the surface of the cell membrane, decreasing the surface potential and increasing the surface tension, causes the phenomena of chemotaxis, phagocytosis and pinocytosis. Cell division, considered in the terms of the surface energy, requires an adequate supply of considerable quantities of energy inversely proportional to the surface potential value. In case of a reduction of the distance between the cells, their surface potential and the energetic barrier of the cell division processes increases, and causes contact inhibition of cell division. Due to their high charge, division of neoplastic cells is inhibited much later than division of normal cells, or is completely ininhibited due to geometric conditions. Fusion of the cell membrane in the intra-cellular and intercellular processes is a reverse process in relation to the cell division. 相似文献
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Acute and chronic toxicity tests for malathion, diazinon, copper (Cu), mercury (Hg), lead (Pb), zinc (Zn), nickel (Ni), and
iron (Fe) were conducted. Mortalities ofBarilius vagra andCyprinus carpio (common carp) were variable but LC50-96 hr were similar for pesticides. AdultB. vagra seem to be more sensitive to malathion than juvenile carp. Both juvenile carp and adultB. vagra were extremely sensitive to diazinon. Long-term exposure to pesticides modified morphology and behavior. The LC50-96 values
for Cu, Hg, and Pb were 0.3, 0.16, and 0.44, respectively, for smaller fish and 1.0, 0.77, and 1.33, respectively, for larger
fish. Replicate LC50 values for Zn, Ni, and Fe were somewhat variable, and for these metals, the size of the fish seemed to
affect response because LC50 values increased as fish size increased. Cooper, Pb, Zn, and Fe residues following exposure to
sublethal concentrations of these metals for 15 d were significantly greater in whole juvenile common carp than in controls. 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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H. -Dietmar Behnke 《Plant Systematics and Evolution》1993,186(3-4):231-243
The sieve-element plastids of 69 species of theCaryophyllales were investigated by transmission electron microscopy. All contained the specific subtype-P3 plastids characterized by a peripheral ring of protein filaments. The presence or absence of an additional central protein crystal and their shape being either polygonal or globular as well as the average sizes of the sieve-element plastids are useful features in the characterization of some families.—Barbeuia contains sieve-element plastids that confirm its placement within thePhytolaccaceae. Lyallia differs fromHectorella by including small starch grains in their sieve-element plastids, which otherwise by their globular crystals negate a closer connection to theCaryophyllaceae. The lack of a central protein crystal in its form-P3fs plastids placesMicrotea best within theChenopodiaceae. Sarcobatus, a so far uncontested member of theChenopodiaceae, contains form-P3cf plastids, i.e., including a central crystal not found elsewhere in this family.Telephium andCorrigiola, shifted back and forth betweenMolluginaceae andCaryophyllaceae, have form-P3cf(s) plastids with a polygonal crystal which favor their placement within theCaryophyllaceae. 相似文献
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The translocation of the radionuclides of Co, Zn, Se, Rb, Y, Tc, and Re into red and green fruits, flesh, seeds, rind, calyxes,
flower, leaves, and stems via the root of the tomato plant at two different growth stages was studied by a multitracer technique.
The contents (%/g) of Co, Zn, Se, and Y in the roots were the highest among the organs, but only small amounts of them were
translocated into the aerial parts after 5 d cultivation with a multitracer. In contrast, Rb, Tc, and Re showed rapid translocation
into the stems and leaves from the root. In the plants cultivated for 95 d with a multitracer, Zn, Se, and Rb distributed
in all of the organs, Co in the organs except for flowers, and Y, Tc, and Re in the limited organs. The translocation ratio
of the elements for the edible part of the plants cultivated for 95 d decreased in the order of Rb>Zn>Co≈Se>Tc≈Y>Re. The transfer
factor of the elements for tomato fruit was determined to be in the range of 10−5–10−2. The characteristic translocation behavior of the elements gives us fundamental information on the assessment of pollutant
uptake by the tomato plant. 相似文献
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Lawrence A. Pervin 《Human ecology: an interdisciplinary journal》1978,6(1):71-105
A review is presented of issues relevant to the definition, measurement, and classification of stimuli, situations, and environments. Problems such as the lack of adequate definitions of concepts, error and bias in measurement procedures, confusion between measurement of a concept and measurement of its behavioral effects, and the lack of agreement among alternative measures are emphasized. It is suggested that concepts be defined in terms of objective characteristics while allowing for the study of the transactional relationship between organism and environment. The work of the ethologists in defining stimuli while studying their relationship to different organismic states and situational contexts is emphasized in this regard. Following Brunswik, it is also suggested that wherever possible there be a representative sampling of variables in natural settings.
Note from the editors: From time to time, Human Ecology will publish a review article. Our first in this series is a review by a psychologist of basic definitional and conceptual problems in environmental studies.This paper was prepared while the author was a Visiting Research Fellow at the Educational Testing Service. The support of ETS and my colleagues in the Division of Psychological Studies is gratefully acknowledged. The review was also supported in part by a grant from the Rutgers University Research Council. 相似文献