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1.
<正>本文对后黄卷叶蛾质型多角体病毒(Hm cpv)进行了形态、超微结构,核酸性质,组织病理及毒力测定等方面的研究,该病毒的包含体呈六角形或园球形,大小为0.42~2.25μm。病毒粒子为正廾面体,表面具管状突起,大小为42~62nm。Hmcpv对后黄卷叶蛾5龄幼虫的LC_(50)为3.5×10~5PIB/ml,1×10~6PIB/ml的LT_(50)为10.4天。  相似文献   

2.
从内蒙古太仆寺旗自然死亡的柳毒蛾虫尸中分离提纯多角体.其平面图呈不规则形状,有三角形、四~六边形和近圆形.大小相差悬殊,直径在0.94~2.47μm之间.约有56.4%的多角体在1.60~2.10μm之间,平均为1.78μm.多角体硷解后释放出短杆状病毒束,大小为204~416nm×104~294nm之间,有42%的病毒束在345~365nm×161~185nm之间,平均为358×170nm.约74.1%的病毒束包埋4~7个病毒粒子.病毒粒子呈杆状.统计表明,约72.8%的病毒粒子长度分布在310~320nm之间,平均大小为315×49um.测定不同龄期幼虫单体多角体产量的结果显示,5龄幼虫比4龄和3龄幼虫高得多.  相似文献   

3.
本文报导了由江苏海安采得的棉铃虫Heliothis armigera(Hübner)核型多角体病毒毒力的生物测定.用不同剂量不同方法感染棉铃虫二令初期幼虫和初孵幼虫,分别测得的剂量与死亡率回归方程式为y=2.56+1.52x、y=2.595+1.198x,前者的LD_(50)为40.91PTB/幼虫,后者的LC_(50)为101.70×10~3PIB/毫升.试验结果表明,江苏海安采得的棉铃虫核型多角体病毒与国外同类病毒制剂相比,毒力是相当高的.用初孵幼虫测定有较多的优点,拟可作为一种常规测定方法.  相似文献   

4.
从新鲜虫尸粗提的病毒,配成5×10~3—5×10~7多角体/ml五种不同浓度,每虫以0.1ml涂于豆叶上,感染2—3令幼虫,分组群养,6天统计结果,幼虫死亡率随病毒浓度增加而上升,5×10~5—5×10~7多角体/ml,可达81.7—92.9%。Lc_(50)为7.9×10~3多角体/ml,上、下置信限分别为9.88×10~4,6.38×10~2多角体/ml.LT_(50)5×10~6,5×10~7,5×10~5多角体/ml分别为3.7,4.1,4.5天.Lc_(50)与LT_(50)值说明NPV对银纹夜蛾具有高度侵染力,在生产上有一定的实用价值。1令幼虫对NPV最敏感,死亡率在95.2%以上,2—3令次之,4令以上敏感性很差。  相似文献   

5.
盗毒蛾核型多角体病毒的分离鉴定   总被引:1,自引:0,他引:1  
作者从自然罹病死亡的盗毒蛾幼虫中分离到一株昆虫病原物,经鉴定,该病原物为盗毒蛾核型多角体病毒(PsNPV),该病毒包涵体多数呈三角形、四边形,部分呈多角形,其大小为1000~2000nm;病毒粒子呈杆状,为单粒包埋型(SEV),其大小为(250~350)nm×(40~60)nm.通过感染试验测定了盗毒蛾核型多角体病毒的毒力,结果显示其LC50为3.34×104PIB/mL;以3×106PIB/mL和3×105PIB/mL两种浓度感染盗毒蛾幼虫,测得LT50分别为5.78d和6.24d.  相似文献   

6.
本文试验结果表明,影响草原毛虫核型多角体病毒产量的最主要因子是病毒浓度,其次是饲毒时幼虫的虫龄,饲毒浓度和虫龄的组合.在四龄初采用1.5×10~6PIB/ml 的病毒浓度饲毒48小时得到了病毒增殖的最高产量.  相似文献   

7.
用1×109PIB/g斜纹夜蛾核型多角体病毒·15%,虫酰肼悬浮剂进行了甘蓝斜纹夜蛾的田间药效试验。结果表明:供试药剂对甘蓝斜纹夜蛾具有良好的防治效果,田间制剂用量1 500 g/hm2时,药后3天对甘蓝斜纹夜蛾幼虫的防效达到80%,以上,且持效期达14 d,显著优于对照药剂1×109PIB/g斜纹夜蛾核型多角体病毒可湿性粉剂1 500 g/hm2的防效和持效期,说明1×109PIB/g斜纹夜蛾核型多角体病毒·15%,虫酰肼悬浮剂在防治甘蓝斜纹夜蛾上具体良好的推广应用前景。  相似文献   

8.
从豆田采到自然罹病死亡的银纹夜蛾幼虫,经分离鉴定其病原体是一种核型多角体病毒。感病幼虫体色由淡绿变为黄绿以至黄白色,体节肿大,倒垂死亡,体壁脆软,常液化流出淡褐色脓液,无嗅味。切片观察幼虫受害组织,主要是表皮细胞、血细胞、脂肪体,气管基质及中肠上皮细胞,此处丝腺、肌肉细胞也被侵染。病变主题表现为细胞核膨大,核内充满大量多角体。电镜观察多角体呈正三边形,直径1.34u,病毒粒子杆状,大小346×57.8nm呈单粒包埋。根据国际病毒分类与命名系统,此病毒属于杆状毒科(B aculoviridae)、杆状病毒属(Baculovirus)、或核型多角体病毒A亚组,定名为银纹夜蛾核型多角体病毒。  相似文献   

9.
本实验分离、鉴定和扩增了扁刺蛾核型多角体病毒TsNPV。初步的生测实验表明:1×10~7PIB/m L、1×10~6PIB/m L、1×10~5PIB/m L、1×10~4PIB/m L、1×10~3PIB/m L感染扁刺蛾幼虫后2 d内扁刺蛾幼虫出现了死亡;扁刺蛾幼虫死亡率随着感染剂量增加而相应提高,1×10~7PIB/m L、1×10~6PIB/m L、1×10~5PIB/m L 3个浓度感染扁刺蛾幼虫后8-9 d内,扁刺蛾幼虫死亡率都达到了100%; 1×10~7PIB/m L、1×10~6PIB/m L、1×10~5PIB/m L 3个浓度的的半至死时间都为4 d左右、1×10~4PIB/m L、1×10~3PIB/m L、1×10~2PIB/m L、1×10~1PIB/m L的4个浓度的半至死时间分别为6 d、7 d、8 d和8 d,表明此毒株具有很好的杀虫效果。  相似文献   

10.
茶尺蠖核型多角体病毒茶园应用研究   总被引:2,自引:0,他引:2  
本文报告了应用茶尺蠖核型多角体病毒(EoNPV)在茶园防治茶尺蠖的研究结果。在茶尺蠖发生的第一、五代和有些年份的第二代(气温低于28℃左右),可以EoNPV单独使用,用量为7.25×10~9~1.5×10~(10)PIB/亩;而第三、四代和有些年份的第二代(气温高于28℃)则以EoNPV与20%杀灭菊酯乳油混用,用量各为1.5~3.O×l0~(10)PIB/亩和3ml/亩。布毒器具宜用雾滴较细的喷雾器;使用时期以幼虫2、3龄前为适,提倡于卵孵化期使用。采取上述措施的茶园示范试验中,第一、二和五代防治后第14天死亡率为96.67—100%;第三、四代为77.75—100%。  相似文献   

11.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.  相似文献   

12.
何延凌 《科技信息》2008,(4):258-258
Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women's language from these perspectives: pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women's language, more attention should be paid to language use in social context. What's more, the linguistic phenomena in a speaking community can be understood more thoroughly.  相似文献   

13.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。  相似文献   

14.
As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.  相似文献   

15.
In the 19th century the society was controlled by men, and women were just appendants of them, they had not any rights and freedom. But Jane was an exception, she showed some characteristics of early feminist. Jane showed her characteristics of feminism in three aspects: rebellion, equality, and independence. These characteristics were helpful to her success, and feminism is the only way out for women of that time.  相似文献   

16.
正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-  相似文献   

17.
We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-  相似文献   

18.
正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that  相似文献   

19.
For molecular systems,the quantum-mechanical treatment of their responses to static electromagnetic fields usually employs a scalar-potential treatment of the electric field and a vector-potential treatment of the magnetic field.Although the potential for each field separately is associated with the choice of an(unphysical)origin,the precise choice of the origin for the electrostatic field has little consequences for the results.This is different for the  相似文献   

20.
Franck-Condon factors bridge the gap between theoretical modeling and experimental observations for molecular electronic spectroscopy and electron transfer.Under the displaced harmonic oscillator approximation,multidimensional Franck-Condon factors are decomposed into a product of many one-dimensional(1D)Franck-Condon(FC)factors,and each 1D-FC factor is associated with one Huang-Rhys factor that determines the leading contribution of  相似文献   

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