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1.
虫霉目真菌和蚜茧蜂是蚜虫的重要专性生防因子，在田间生态系统中存在“共位共处”的现象。本文开展了以新蚜虫疠霉和烟蚜茧蜂为代表的虫霉目真菌和蚜茧蜂在有翅蚜蚜群中的互作研究。有翅蚜“孢子浴”接种新蚜虫疠霉后不同时间间隔（0 d，1 d，2 d）再进行蚜茧蜂处理，试验结果表明：各处理间的蚜虫感病率差异显著，且均高于60%；处理间的僵蚜率则差异不显著，且均低于15%。而有翅蚜先经寄生再“孢子浴”接种的5组不同间隔时间（1 d，2 d，3 d，4 d，5 d）处理试验的结果表明，组间有翅蚜的僵蚜率呈极显著差异，感病率也呈极显著差异，且僵蚜率和感病率在间隔4 d组出现明显分界。因此，在实验室条件下的有翅蚜蚜群中，新蚜虫疠霉的侵染比烟蚜茧蜂的寄生更具竞争优势，但它们之间的互作关系不是取代关系，而是迭代关系。本试验为蚜虫专性病原真菌（特别是虫霉目真菌）更好地联合蚜茧蜂在蚜虫生物防治中开展应用提供科学依据。 相似文献
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[目的]探明新蚜虫疠霉的空间分布特点,为进一步研究蚜虫新蚜虫疠霉病害流行规律及田间释放病原菌防治桃蚜提供依据.[方法]调查甘蓝田新蚜虫疠霉感染致病桃蚜密度,采用Taylor幂法与Iwao回归法分析新蚜虫疠霉的空间分布特征.[结果]新蚜虫疠霉在甘蓝田呈聚集分布中的负二项分布,公共K值为2.87.Iwao直线回归方程拟合式为(m*)=0.12+1.36 m(R=0.99),Taylor幂公式为lg(v)=0.35+1.69 lgm (R=0.96).在不同季节,其空间分布的拥挤度差异显著(F=5.34,p＜0.01),7-9月平均拥挤度最高,而1-3月和10-12月最低.精度分别为0.1、0.2、0.3和0.5时的理论抽样数公式分别为n=430.26/x+138.30、n=107.56/x+34.57、n=47.81/x+15.37和n=17.21/x+5.53.当被新蚜虫疠霉感染罹病桃蚜密度较低,即低于每样方5头时,以模型n=17.21/x+5.53较为适宜,在较高密度,即每样方10头/株以上时,以模型n=107.56/x+34.57较宜.[结论]新蚜虫疠霉在甘蓝田均呈聚集分布中的负二项分布,聚集原因是新蚜虫疠霉生物学特性和环境因素.在6-8月,对该菌侵染蚜虫的总体理论抽样以抽查20株左右样方为宜,而在其他季节,抽查30株左右样方为宜. 相似文献
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选用栽培较多的两种十字花科蔬菜——青菜和结球甘蓝,探讨蔬菜种类及温度对桃蚜和萝卜蚜增殖能力的综合影响。在室内进行蔬菜种类、温度、蚜虫种多因子试验,并结合大田系统调查数据综合分析。结果表明,两种菜蚜混合种群的增长能力在青菜上比在甘蓝上高,在16-18℃比在24-25℃下略高,且蔬菜种类与蚜虫种、温度与蚜虫种每两个因子之间有显著的交互作用,即在甘蓝上两种蚜虫增殖能力较各自在青菜上的水平下降幅度不一,桃蚜比萝卜蚜下降幅度大,温度从16-18℃上升到24-25℃,萝卜蚜的增殖能力基本不变,而桃蚜则明显下降。在田间,天敌对菜蚜数量增长有明显的抑制作用。 相似文献
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《中国植保导刊》2018,(12)
2018年,于江苏句容研究了释放异色瓢虫、喷洒50%氟啶虫胺腈水分散粒剂对桃园桃蚜的防治效果。结果表明,释放比例为1∶10～15、1∶15～20的异色瓢虫释放处理和化防处理对桃园桃蚜均有显著抑制作用,对桃树新梢保护效果较好。防治后7d,异色瓢虫释放区释放比例1∶15～20的处理防效达90.1%;防治后14 d,异色瓢虫释放区防效均有所下降,化防区防效则达到最高,防效为99.5%。从防治效果和经济成本角度综合考虑,建议加强早期虫情监测,发现少量桃蚜时按照1∶15～20的比例释放异色瓢虫;桃蚜虫量较多时,按照1∶10～15的比例释放异色瓢虫或使用氟啶虫胺腈喷雾防治。 相似文献
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对昆虫病原体的直接取样、检测及定量化能够直接反映昆虫流行病学调查中的病原体丰度。本文以在田间蚜群中广泛流行的虫霉目真菌新蚜虫疠霉为研究对象,通过对不同来源的新蚜虫疠霉样品的DNA提取测试,建立Lysis提取结合Chelex-100方法的PCR检测技术体系,并以此方法为支撑进行了田间麦蚜新蚜虫疠霉流行病的调查验证。结果表明改良的Chelex方法不仅为昆虫病原真菌的田间流行学调查提供了一个快速、准确的评价方法,而且在其他真菌的核酸快速、痕量检测方面也可能具有重要的应用潜力。 相似文献
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低剂量杀虫剂对星豹蛛捕食桃蚜功能模型的影响 总被引：3，自引：3，他引：0
为明确杀虫剂对捕食性天敌蜘蛛对蚜虫控制作用的影响,采用药膜法和点滴法测定了星豹蛛Pardosa astrigera和桃蚜Myzus persicae对4种杀虫剂的敏感性,并利用HollingⅡ捕食功能反应模型分析了杀虫剂作用下星豹蛛对桃蚜的捕食功能反应。结果表明:桃蚜和星豹蛛均对阿维菌素最敏感,其对应的LD50和LC50最低,分别为4.94×10-4 μg/头和0.14 mg/L;吡虫啉和啶虫脒居中,毒死蜱最低;前三者的LD50依次是毒死蜱的127.47、72.05和1.67倍,LC50依次是毒死蜱的261.36、3.60和4.08倍。杀虫剂处理星豹蛛后对桃蚜的功能反应类型基本符合HollingⅡ模型;除3.0、4.5 mg/L啶虫脒处理外,不同杀虫剂作用下星豹蛛对桃蚜的处理时间长于对照组的0.016 d,最大日捕食量小于对照组的60.7头;同种杀虫剂作用下,随着浓度增加平均日捕食量逐渐降低,处理时间延长,瞬间攻击率下降;寻找效应随着桃蚜密度和杀虫剂浓度的增大而下降。表明低剂量杀虫剂处理星豹蛛后延长了其对猎物的处理时间,降低了瞬间攻击率,减少了日捕食数量,从而降低了对猎物的控制作用。 相似文献
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桃树谢花后,果枝上接种不同数量的桃蚜[Myzuspersicae(Sulzer)],结果得出不同蚜虫数量均能引起桃树枝叶明显受害,并且随着虫量增加受害程度加重;每果枝蚜量达20～60头时,导致果品产量明显损失;各接虫量都未引起果品糖度显著差异。研究结果说明,桃树谢花后为桃蚜防治的关键时期,每果枝蚜量20头可以作为防治参考指标。 相似文献
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《中国生物防治学报》2014,(6):779
新蚜虫疠霉是蚜虫专性病原真菌,是流行潜力极大的昆虫种群自然调节因子,在桃蚜蚜群中大量流行。为了研究昆虫与虫霉的相互关系以及虫霉病在昆虫种群中的流行规律,陈相波等(正文731~735页)通过对不同来源的新蚜虫疠霉样品的DNA提取测试,建立Lysis提取结合Chelex-100方法的PCR检测技术体系,并以此方法为支撑进行了田间麦蚜新蚜虫疠霉流行病的调查验证。改良的Chelex方法不仅为昆虫病原真菌的田间流行学调查提供了一个快速、准确的评价方法,而且在其他真菌的核酸快速、痕量检测方面也可能具有重要的应用潜力。 相似文献
10.
桃蚜、萝卜蚜发育速率与温度的关系 总被引：6，自引：0，他引：6
测定了桃蚜、萝卜蚜在一系列恒温、变温下的发育速率,结果表明:(1)低于18℃桃蚜比萝卜蚜发育快,19—27℃范围内两种蚜虫发育速率基本一致,高于27℃萝卜蚜比桃蚜发育快;(2)根据恒温下数据所拟合的logistic曲线准确地反映了变温下发育速率与温度的关系,可用于描述和预测种群在自然变温下的发育进度;(3)发育起点温度和有效温积常数两个统计量会随试验温度的波动方式和幅度不同而异,但只要数据和计算方法适当,还是能用于种群模拟和预测的。 相似文献
11.
为探求诱导樟巢螟(Orthaga achatina Butler)滞育的临界光周期及敏感虫态(期),在室内25℃和28℃下观察不同光周期对樟巢螟滞育的影响,并利用不同长光照和短光照组合对樟巢螟幼虫的不同龄期进行处理,掌握樟巢螟的敏感虫态(期)。结果表明光周期为L∥D=12.0h∥12.0h,L∥D=12.5h∥11.5h,L∥D=13.0h∥11.0h时,在25℃下,樟巢螟的滞育率分别为100%,94.80%和97.60%;在28℃下,滞育率分别为98.55%,99.05%和83.50%。当光周期为L∥D=13.5h∥10.5h,在25℃和28℃下,樟巢螟的滞育率分别为42.38%和34.05%。樟巢螟属长日照发育型昆虫,在25℃时诱导滞育的临界光周期是13.565h,在28℃时是13.364h。25℃时樟巢螟对光照反应最敏感的时期是4～5龄期,1～3龄次之,卵期最不敏感。 相似文献
12.
七星瓢虫(Coccinella septempunctata)捕食苜蓿斑蚜(Therioaphis trifolii)的数量与苜蓿斑蚜密度呈负加速曲线关系,功能反应符合Holling-Ⅱ型模型,为Na=1.024 2N/(1+0.003 3N),捕食苜蓿斑蚜的数量随斑蚜密度增加而增大,但寻找效应随之而降低,日最大捕食量为313头。在10～25℃下,七星瓢虫捕食率y与温度x的关系为y=2.4 1x+3 0.0 7 5,在2 5～3 5℃间的捕食率y与温度x的关系为y=1 2 0-1.2x,2 5℃下七星瓢虫捕食率最高,捕食率达9 0.5%。在种内干扰条件下,其捕食作用率E随天敌密度P的增加而减少,干扰反应数学模型为E=0.4 1 9 3P-0.5 0 1 8。随着叶片数量增多,七星瓢虫和斑蚜之间的距离相对增大,造成捕食率的下降。 相似文献
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A series of experiments in the laboratory and greenhouse, were designed to test the possible causes of the field resurgence of the aphid Myzus persicae. Stimulation of reproduction occurred at topical dosages of around the LD5 value. Residual film tests indicated a significant depression in fecundity when aphids were held on sub-lethal deposits of fenvalerate, even at dosages below the LD5 value. Trends in the population build-up experiments in the greenhouse suggested there may be some stimulation when aphids are confined to aged deposits of fenvalerate 7 days after treatment, but the slight increase was not significant. 相似文献
14.
温度对小麦矮腥黑穗病菌冬孢子萌发影响的试验结果表明,TCK冬孢子在-2～12℃范围内都可以萌发,5℃为最佳萌发温度。同一分离菌冬孢子在不同温度处理的萌发特性和萌发率有差异;不同分离菌冬孢子在相同温度下的萌发特性和萌发率有很大差异。在5℃下5个分离菌中,冬孢子萌发起始时间最短的为15 d,最长为35 d,培养60 d时分离菌Tt1、Tt2、Ty、Tm和Tu冬孢子的萌发率分别为86.4%、23.9%、23.3%、44.3%和81.0%。根据分离菌Tt2不同温度下培养50 d时的萌发率,建立了萌发率(Y)与温度(X)的模型为Y=0.150 8 exp[-0.02949(X-4.957 6)]2,此结果为TCK的风险评估提供了基础数据。 相似文献
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Ralf Nauen 《Pest management science》1995,44(2):145-153
With a combination of biological, analytical, electrophysiological, and video-optical methods, it was possible to show that low concentrations of the new chloronicotinyl insecticide, imidacloprid, strongly affect the behaviour of Myzus persicae (Sulz.), leading eventually to the death of the aphids. Tests to elucidate the biological properties were performed under laboratory conditions with cabbage leaf petioles placed in insecticidal solutions over different periods of time. LC15(24h) values were considered as low concentrations and calculated for imidacloprid and pirimicarb, respectively. Imidacloprid at low concentrations depressed the honeydew excretion of apterous adults of M. persicae by almost 95% within 24 h without affecting the vitality of the majority of aphids, whereas, at equitoxic concentrations, pirimicarb showed much weaker effects on honeydew excretion, which strongly coincided with mortality. In choice experiments with alate morphs of M. persicae over 48 h, their larvae almost always occurred on the untreated control leaf, and were not found on the leaf which was treated systemically with low concentrations of imidacloprid. Apterous aphids placed on cabbage leaves systemically treated with low concentrations of imidacloprid showed nearly the same decrease in weight as untreated starving aphids, suggesting that their death was caused by starvation. Aphids that were moved from imidacloprid-treated to untreated leaves after 24 h began feeding on the latter and showed a steady increase in weight and honeydew production. This suggests that the behavioural response is reversible. Aphids on pirimicarb-treated (equitoxic dose) leaves showed no decrease in weight. Electrical penetration graphs revealed that M. persicae on artificial membranes containing imidacloprid probed more often before feeding than aphids on control sachets. Time-lapse videofilming of apterous adults placed on cabbage leaves revealed a migration from the leaf treated with low concentrations of imidacloprid to an untreated leaf. From the results of these experiments and the observed symptomatology it is possible to postulate two different and dose-dependent modes of action of imidacloprid on M. persicae: (1) the well-known mode of action with visually obvious irreversible symptoms (paralysis, tremor, uncoordinated leg-movement) at field rates, and (2) the reversible starvation response as an antifeedant effect, which is not coupled with typical symptoms of neuronal disorder, at lower concentrations. 相似文献
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BACKGROUND: Twenty‐three isolates of Metarhizium anisopliae (Metschnikof) Sorokin and M. acridum (Driver & Milner) JF Bischoff, Rehner & Humber from non‐aphid host insects around the globe were evaluated for their aphid biocontrol potential, which is not well known. RESULTS: The apterous adults of green peach aphid Myzus persicae (Sulzer) were exposed to the fungal sprays of 11.5, 99 and 1179 conidia mm?2 and blank control in three leaf‐dish bioassays. All the tested isolates except one were proven to be infective to the aphid species at 21 ± 1 °C and 14:10 h light:dark photoperiod, causing corrected mortalities of 10.1–95.3% at the high spore concentration. The data from ten isolates causing > 50% mortality at the high concentration were found to fit a time–concentration–mortality model well, yielding parameters for the estimates of their LC50 and LT50 that vary with post‐spray time and spore concentration respectively. Four isolates of M. anisopliae (ARSEF 759, 4132, 2080 and 576) had LC50 values of 44–80 conidia mm?2 on day 8 and LT50 values of 4.9–6.8 days at 100 conidia mm?2, with 91–98% of the killed aphids being well mycotised after death. CONCLUSION: The Metarhizium infectivity to M. persicae differs greatly among the tested isolates. The four mentioned isolates with desired virulence and sporulation potential are excellent candidates for microbial control of aphids. Copyright © 2010 Society of Chemical Industry 相似文献
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The response of susceptible (S), moderately resistant (R1) and strongly resistant (R2) peach-potato aphids, Myzus persicae (Sulz.) to organophosphorus, carbamate and pyrethroid insecticides was tested by a leaf-dip bioassay. The aphids were placed on potato leaves (dipped in insecticide solutions 1–2 or 24 h before infestation) and their mortality examined 48 h later. R1 aphids were virtually susceptible to most of the carbamates, demephion and acephate, but were slightly to moderately resistant (2.1–9.4 times) to permethrin, cypermethrin and (S)-α-cyano-3-phenoxybenzyl (1R)-cis-3-(2,2-dibromovinyl)-2,2-dimethylcyclopropanecarboxylate (I), (NRDC 161), to 5,6,7,8-tetrahydro-2-methylquinolin-4-yl dimethylcarbamate (II), (Hoechst 25 682) and demeton-S-methyl. R2 aphids resisted more strongly or very strongly (between 65 and 1280 times) the pyrethroids, demeton-S-methyl (×94), II (×83) and demephion (×9), and were slightly to moderately (2–5 times) resistant to acephate, pirimicarb, ethiofencarb and 2-(dimethylcarbamoyloxyimino)-3-methoxyimino-N,N- dimethylbutyramide (III), (DPX 3853). Both resistant strains were susceptible to nitrilacarb [4,4-dimethyl-5-(methylcarbamoyloxyimino)pentanenitrile] complex (1:1) with zinc chloride (IV), (AC 85 258). The implications of these results in terms of practical aphid control are discussed. 相似文献
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Ron F van Toor Gaynor L Malloch Eric A Anderson Greg Dawson Brian Fenton 《Pest management science》2013,69(1):93-103
BACKGROUND: The accuracy of predicting the survival of insecticide‐resistant aphids following the application of commonly used insecticides from the carbamate, the pyrethroid, a mix of the two or the neonicotinoid chemical classes was evaluated in a potato field in Scotland. Equal proportions of five genotypes of the peach‐potato aphid, Myzus persicae (Sulzer), with none, resistance to dimethyl‐carbamates, resistance to pyrethroids or combinations conferring resistance to both chemical classes were released into potato field plots. The insecticides were sprayed separately onto these plots, the aphid populations were analysed after 6–8 days and the process repeated. RESULTS: For each assessment after the three separate spray events, plots treated with the carbamate had 48, 147 and 28%, those treated with pyrethroid 53, 210 and 89%, those treated with carbamate/pyrethroid 28, 108 and 64% and those treated with neonicotinoid 43, 55 and 11% of the numbers of M. persicae by comparison with untreated controls. Only the proportions of surviving aphids from the genotype containing no insecticide resistance traits and the genotype containing elevated carboxylesterases matched ratios predicted from the selective advantage afforded by the resistance traits alone. Survival of aphids from the other three genotypes that carried 1–3 of the insecticide resistance traits differed from expectations in all cases, possibly owing to physiological differences, including their vulnerability to predators and hymenopterous parasitoids present at the site and/or their carrying unknown insecticide resistance mechanisms. CONCLUSION: Control strategies based on knowledge of the genetically determined insecticide resistance profile of an M. persicae population alone are insufficient. Hence, other important factors contributing to aphid survival under insecticide pressure need to be considered. Copyright © 2012 Society of Chemical Industry 相似文献
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释放异色瓢虫对北京温室甜椒和圆茄上桃蚜的控害效果 总被引：2，自引：1，他引：1
为评价异色瓢虫在温室条件下对桃蚜的控害能力及效益,在甜椒和圆茄生产温室中以生物农药防治为对照,开展释放异色瓢虫控制桃蚜的示范试验,分析天敌害虫的种群动态变化,并计算防治成本。结果显示:异色瓢虫能够持续控制甜椒温室中桃蚜种群密度,其定殖率在蚜虫暴发高峰期时最高,为64%;且甜椒产量及经济效益高于生物农药防治。在圆茄温室中,前期释放的异色瓢虫使桃蚜高峰延缓1周出现;在增加瓢虫释放量后,1周内桃蚜种群密度下降了79%,且瓢虫定殖率达到86%,控害效果较好。表明通过生产期全程监测天敌-害虫的种群动态,在植株定植15 d后每周确定益害比,通过2~3个月持续释放异色瓢虫,可有效、持续控制整个生产期桃蚜为害。 相似文献