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1.
 通过对烟粉虱Bemisia tabaci Gennadius 的两种优势寄生蜂浅黄恩蚜小蜂Encarsia sophia Girault & Dodd 和海氏桨角蚜小蜂Eretmocerus hayati Zolnerowich & Rose 的生殖系统结构与卵巢发育特点的研究,明确了影响两种寄生蜂不同寄主处理行为的生理机制。两种寄生蜂雌性生殖系统各包括1 对卵巢、1 对侧输卵管、中输卵管、受精囊、产卵管和产卵鞘。浅黄恩蚜小蜂的产卵器细长笔直较锋利,海氏桨角蚜小蜂产卵器扁平且尖端向上弯曲,这与两种寄生蜂不同的产卵机制相吻合。浅黄恩蚜小蜂和海氏桨角蚜小蜂雌蜂初羽化时体内成熟卵子数量存在明显差异,但随着时间的推移和营养的补充,两种寄生蜂卵巢内成熟卵子的数量都会显著增加。两种寄生蜂均为卵育型寄生蜂。  相似文献   

2.
日本恩蚜小蜂是烟粉虱的有效寄生蜂,在15、20、25、30、35℃这5个恒温条件下观察日本恩蚜小蜂的生长发育情况,记录卵、幼虫、预蛹、蛹和卵-成虫的发育历期,计算日本恩蚜小蜂各虫态的发育起点温度和有效积温。结果表明,温度显著影响日本恩蚜小蜂不同虫态的发育历期。在15-35℃范围内,日本恩蚜小蜂的不同虫态发育历期均随着温度的升高而逐渐缩短。日本恩蚜小蜂卵、幼虫、预蛹、蛹、卵-成虫的发育起点温度分别为9.62、8.82、9.00、7.03、8.44℃,有效积温分别为29.10、108.32、14.29、90.59、239.08 d·℃。  相似文献   

3.
美洲斑潜蝇蛹的抗逆性研究   总被引:1,自引:0,他引:1  
对美洲斑潜蝇在温度、湿度和覆土等逆境条件下蛹的羽化发育进行了研究,结果表明:美洲斑潜蝇蛹较耐高温,在34℃条件下能较顺利发育、羽化,但对低温较敏感,0℃下基本不能羽化;初羽化的蛹不耐水浸,对土壤湿度敏感;覆土深度对蛹的羽化有明显影响,羽化率随覆土深度的增加而迅速下降。  相似文献   

4.
惠东黄蚜小蜂是林业重要入侵害虫—松突圆蚧的本地寄生性天敌之一,开展惠东黄蚜小蜂的生物学特性研究,可为其将来的人工保护和利用提供依据.研究结果表明,成蜂的多数形态特征与其近缘种相似,但在触角式、产卵器的相对长度方面存有明显区别;在15~35℃,成蜂个体寿命随着温度升高而缩短且雌蜂寿命长于雄蜂;在(25±1)℃,RH(70±10)%条件下,卵期发育历期为(2.3±0.4)d,幼虫期(12.8±1.5)d,蛹(8.5±0.8)d,全世代历期为23.6 d,有效积温为301日度,发育起点温度9.227℃.成蜂羽化后,即可立即取食20%蜜水,羽化主要在白天12:00~16:00进行,成蜂具有较强正趋光性;在林间,虫口密度高峰发生于4~6月,种群性比为7.15∶1,可能存在产雌孤雌生殖现象.  相似文献   

5.
通过室内实验研究不同贮藏条件对薜荔榕小蜂雌蜂存活寿命的影响,结果表明,小蜂存活的最佳条件是温度为10℃,相对湿度为98%,无光照并添加适量体积分数2%蜂蜜液.在此条件下,寿命最长的小蜂可存活15 d,湿度和温度对小蜂存活影响达到极显著水平,而食物(体积分数2%蜂蜜液)和光照对小蜂存活影响达到显著水平.不同因素对小蜂存活寿命的影响程度从大到小依次为:湿度温度食物光照.温度和湿度以及温度和光照之间没有表现出显著的互作效应.  相似文献   

6.
本研究针对人工繁育白蛾周氏啮小蜂Chouioia cunea Yang过程中出现的小蜂滞育现象,对其滞育诱导的光周期反应及敏感光照虫态进行了调查。结果表明:沈阳地区的白蛾周氏啮小蜂属长日照型昆虫,以老熟幼虫进入滞育状态,但在不同的温度条件下诱导滞育的临界光周期不同,在18℃时诱导滞育的临界光周期处于13L∶11D和14L∶10D之间;在21℃和24℃时诱导滞育的临界光周期变短,处于12L∶12D和13L∶11D之间。白蛾周氏啮小蜂滞育诱导的敏感光照虫态为幼虫期,且以幼虫的后期最为敏感,但整个幼虫期接受短光照对滞育的形成更为有利。通过观察白蛾周氏啮小蜂滞育后在18℃,21℃,24℃和30℃的恒温条件下的发育历期,由最小二乘法计算出白蛾周氏啮小蜂老熟幼虫滞育后发育起点温度和有效积温分别为14.60±0.31℃和209.38±8.72日.度。这些结果可为进一步研究白蛾周氏啮小蜂的种蜂长期保存技术和指导商品蜂生产,正确把握放蜂时机提供理论依据。  相似文献   

7.
以杨梅园等果园害虫黑腹果蝇(Drosophila melanogaster)及其蛹期寄生蜂蝇蛹俑小蜂(Spalangia endius)为对象,在温度25±1℃、相对湿度(60±5)%以及光周期14L:10D的室内条件下,构建了蝇蛹俑小蜂实验种群生命表.结果表明雌蜂和雄蜂的成蜂寿命分别为17.28±5.29d和17.97±6.76d,平均每头雌蜂有60.31±35.08个后代,后代中雄性百分比为(28.08±13.29)%.雌雄蜂羽化后的生命期望分别为16.78d和17.47d.在实验条件下,蝇蛹俑小蜂种群内禀增长率(rm)和周限增长率(λ)分别为0.14±0.0009和1.16±0.001;净生殖率(R0)为45.17±1.05;世代时间(T)和种群倍增时间(DT)分别为26.31±0.07d和4.79±0.03d.研究表明,蝇蛹俑小蜂在实验室条件下可以利用黑腹果蝇完成生活史,对果蝇存在控制效果.  相似文献   

8.
条纹叶甲不同发育时期卵巢解剖表明,卵巢发育可分5级:乳白透明期、卵黄沉积期、成熟待产期、产卵盛期、产卵末期.本文描述了卵巢不同发育时期的识别特征,为预测发生期与发生量提供依据.同时对条纹叶甲的羽化节律作一研究:(1)在室外自然暗条件下,成虫的羽化高峰为11—17时;(2)在室内自然温度下进行连续光照与连续黑暗处理,两种处理的羽化高峰均为11—17时;(3)在25℃恒温下进行连续光照与连续黑暗处理,黑暗条件下羽化高峰期为8—14小时;光照条件下羽化高峰期为14—20时,在2—5时羽化率最低.这表明成虫羽化受光周期和温度的影响且具有明显的昼夜节律.  相似文献   

9.
扫描电镜观察桨角蚜小蜂(Eretmocerus sp.)和浅黄恩蚜小蜂(Encarsia sophia)雌成虫的感觉系统,结果如下:2种蚜小蜂的触角上具毛形感器、锥形感器、板形感器、刺形感器、坛形感器、B(o)hm氏鬃毛;复眼上具锥形感器;口器上颚每侧具3根毛状感器,下颚须与下唇须顶端各着生1根刺形感器;足具毛形感器与刺形感器,这些感觉器遍布足的各个亚节,前足具触角清洁器,后足具翅膀清洁器;产卵器上具毛形感器,感觉孔,以及倒钩状突起.  相似文献   

10.
以蛹蜂比为1∶100和柞蚕(Antheraea pernyi Guerin-Meneville)蛹为替代寄主繁殖白蛾黑基啮小蜂(Tetrastichus nigricoxae Yang),测定室内人工繁蜂的最适交配期和接蜂暴露期。结果表明:当小蜂羽化出蜂后交配48~72 h时,寄生率(93.3%~94.2%)、羽化率(87.5%~90.8%)和平均子代出蜂量(1 010.4~1 213.3头)等寄生指标,均高于或显著高于24 h时的值(p<0.05),极显著高于0 h和96~144 h时(p<0.01)的值;当寄主蛹暴露给寄生蜂2~3 d时,寄生率(87.5%~95.8%)、羽化率(86.7%~95.8%)和平均子代出蜂量(1 274.5~1 365.6头)等繁蜂指标也高于或显著高于其他暴露期处理(p<0.05)。综合考虑蜂龄对寄生效果的影响,选择白蛾黑基啮小蜂人工繁殖的最适交配期和暴露期分别为羽化出蜂后2 d和2~3 d。  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.
The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3~4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰~ -7.8‰, PDB) and matrix dolomites (-6.6‰~ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084~0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078~0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.  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.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

16.
There are numerous geometric objects stored in the spatial databases. An importance function in a spatial database is that users can browse the geometric objects as a map efficiently. Thus the spatial database should display the geometric objects users concern about swiftly onto the display window. This process includes two operations:retrieve data from database and then draw them onto screen. Accordingly, to improve the efficiency, we should try to reduce time of both retrieving object and displaying them. The former can be achieved with the aid of spatial index such as R-tree, the latter require to simplify the objects. Simplification means that objects are shown with sufficient but not with unnecessary detail which depend on the scale of browse. So the major problem is how to retrieve data at different detail level efficiently. This paper introduces the implementation of a multi-scale index in the spatial database SISP (Spatial Information Shared Platform) which is generalized from R-tree. The difference between the generalization and the R-tree lies on two facets: One is that every node and geometric object in the generalization is assigned with a importance value which denote the importance of them, and every vertex in the objects are assigned with a importance value,too. The importance value can be use to decide which data should be retrieve from disk in a query. The other difference is that geometric objects in the generalization are divided into one or more sub-blocks, and vertexes are total ordered by their importance value. With the help of the generalized R-tree, one can easily retrieve data at different detail levels.Some experiments are performed on real-life data to evaluate the performance of solutions that separately use normal spatial index and multi-scale spatial index. The results show that the solution using multi-scale index in SISP is satisfying.  相似文献   

17.
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   

18.
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   

19.
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   

20.
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   

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