阿维菌素生物农药防治二斑叶螨药效试验

７０５１杀虫素、集琦虫螨克均属阿维菌素系列生物农药,其主要特点是杀虫、杀螨、广谱、高效、低毒、安全、不易使害虫产生抗性。针对二斑叶螨寄主范围广、食性杂、繁殖速度快、抗药性强的特点,我们特选用以上两种生物农药进行试验、示范,现将结果整理如下。１材料和方...     

阿维菌素与螺螨酯对沾化冬枣截形叶螨的毒力筛选及田间防效研究

为了寻找高效、低毒、持效期长的冬枣截形叶螨防治药剂。本研究采用叶螨栽玻片浸渍法和喷雾法,开展了室内配方筛选试验和田间药效试验。试验结果表明,阿维菌素和螺螨酯以1:9混配时,共毒系数为148.56,表现为明显的增效作用;30%阿维菌素?螺螨酯悬浮剂对冬枣截形叶螨有较好防效,且防效与施药量呈正相关,制剂量8000倍液时与240g/L螺螨酯悬浮剂4000倍液的防效基本相当,持效性明显优于3%阿维菌素水剂。因此,使用30%阿维菌素?螺螨酯悬浮剂防治冬奉截形叶螨推荐使用制剂量为5500~8000倍液。     

新乡棉花叶螨及优势种消长的初步调查

1986—1987年,用制作玻片标本和记录叶片上螨量的方法观察新乡棉区棉花叶螨优势种的消长。结果表明:一、新乡地区棉花叶螨为朱砂叶螨Tetranychus cinnabarinus和截形叶螨T.truncatus构成的复合种群。二、不同年份及同一年份不同时期优势种有变化。1986年朱砂叶螨是优势种,1987年棉花生长初期,朱砂叶螨为优势种,6月中旬后,该螨所占比例开始下降,7月上旬后,截形叶螨成为优势种,并维持优势到危害后期。     

香梨园山楂叶螨种群动态的研究

采用聚集度指标分析了山楂叶螨聚集强度的时序变化,以指数模型进行拟合数量动态,运用最优分割法分析了山楂叶螨在香梨上的种群动态。山楂叶螨在香梨上的空间格局为聚集分布,分布的基本成分为个体群,聚集强度与叶螨的密度有关。山楂叶螨在香梨上呈指数增长,模型为Nt=15.199 4e0.054 t(R=0.913 2**);将山楂叶螨种群动态划分为3个阶段:发展期、高峰期和衰退期。     

亚致死浓度阿维菌素对荔枝叶螨种群发育的影响

于室内条件下研究了亚致死浓度阿维菌素对荔枝叶螨种群发育的影响。采用Potter喷雾法测得阿维菌素对荔枝叶螨成螨的亚致死浓度（LC10和LC30）,并通过生命表方法研究了阿维菌素LC10和LC30浓度处理荔枝叶螨对其生长和繁殖的影响。结果表明:用阿维菌素LC10和LC30浓度处理荔枝叶螨后,与对照相比,其F0代产卵量分别减少79.16%和71.83%,雌成螨寿命亦均明显缩短。F1代幼螨期、产卵前期与对照相比均无显著差异,但卵孵化期、前若螨期、后若螨期均显著延长,其中LC30浓度处理后分别延长41.4%、39.4%和36.1%;F1代产卵量降低、产卵期缩短,其子代雌性比提高;F1代内禀增长率均降低,分别为0.127 3和0.075 8,而对照为0.132 3;世代平均历期缩短,种群倍增时间延长;净生殖率和周限增长率均降低。表明亚致死浓度阿维菌素对荔枝叶螨种群增长有一定的抑制作用。     

棉叶螨种群动态的模糊聚类分析

从种群数量动态和空间动态的统一观出发,运用模糊聚类方法,分析安徽沿江棉区棉叶螨的种群动态,结果表明,棉叶螨种群在时间过程中先后呈点片发生、扩张发生和猖獗发生3种主要动态类型。     

抗梅岭霉素和阿维菌素二斑叶螨种群生命力和繁殖力的研究

采用营养液培养的棉苗饲养二斑叶螨Tetranychus urticae Koch,用梅岭霉素、阿维菌素对其逐代进行抗性选育,至第9代,测定了两个抗性种群的抗性水平、生命力和繁殖力。结果表明:梅岭霉素抗性种群的抗性达7.9倍,其雌成螨寿命、产卵量、卵的孵化率和后代若螨成活率分别比对照增加54.08%、39.93%、6.57%和-15.44%。阿维菌素抗性种群的抗性达5.8倍,其雌成螨寿命、产卵量、卵的孵化率和后代若螨成活率分别比对照增加15.88%、10.87%、5.86%和-9.32%。由此发现梅岭霉素和阿维菌素对二斑叶螨的生长发育和繁殖有一定有利作用,抗性风险性较大,应引起重视。     

阿维菌素与植物精油复配对朱砂叶螨杀螨的增效作用研究

为了得到对朱砂叶螨(Tetranychus cinnabarinus)具有较好杀螨活性的植物精油与阿维菌素复配配方,并为杀螨剂开发应用提供指导,本研究采用喷雾法测定了柠檬草、广藿香、山鸡椒、亚洲薄荷植物精油及阿维菌素对朱砂叶螨的毒力,分别采用共毒因子法和共毒系数法评价了山鸡椒和亚洲薄荷精油对阿维菌素的增效作用和复配最佳...     

二斑叶螨对阿维菌素抗性和敏感品系相对适合度的研究

在室内25℃条件下通过构建实验种群生命表,比较二斑叶螨对阿维菌素抗性品系(R)和敏感品系(S)的一系列生长发育和繁殖特征参数。结果表明:二斑叶螨抗性品系(R)的发育历期、孵化率、幼螨存活率、有效产卵量等诸多指标与敏感品系(S)相比均存在一定的不利性。抗性品系的相对适合度仅为敏感品系的0.53倍,存在适合度缺陷。     

间作大蒜对茄子截形叶螨的防控效果

为明确间作大蒜对茄子截形叶螨Tetranychus truncatus Ehara种群的防控效果,于室内测定了大蒜提取液对截形叶螨卵的毒杀活性及对雌成螨的驱避和产卵选择性影响,并研究了田间不同比例间作大蒜对茄子截形叶螨自然种群的影响。结果表明,用0.05 g/mL和0.10 g/mL大蒜提取液处理后,截形叶螨卵死亡率分别为44.53%和63.53%,均显著高于空白对照;大蒜提取液处理蔬菜叶片72h后,截形叶螨雌成螨和卵的数量分别为16头和141粒,均显著低于空白对照组的23头和236粒;田间茄子和大蒜按1∶1、2∶1或4∶1间作均可降低截形叶螨自然发生数量,其中1∶1和2∶1间作对截形叶螨种群控制显著升高。研究表明,大蒜提取液对截形叶螨雌成螨取食及产卵具有显著的驱避活性;且间作大蒜可以对截形叶螨种群起到明显的抑制作用。     

二斑叶螨对阿维菌素抗性的CAPS标记

为了实现二斑叶螨Tetranychus urticae Koch对阿维菌素抗药性的快速检测,本研究建立了一种叶螨对阿维菌素抗药性的快速分子检测技术,即酶切扩增多态性序列(cleaved amplified polymorphic sequences,CAPS)标记技术,检测二斑叶螨谷氨酸门控氯离子通道(Glu Cl3)基因片段上G326E的突变频率,并采用琼脂浸叶法测定田间5个种群对阿维菌素的抗药性。结果表明,北京密云、顺义、昌平、浙江宁波和海南吉阳5个种群对阿维菌素的抗性倍数分别达1 155.63、1 317.10、844.19、314.95和1 799.69倍,均为极高抗性水平;CAPS检测发现我国二斑叶螨抗性基因存在G326E位点突变,但在供试的5个不同种群中突变频率变异很大,其中北京昌平种群G326E突变频率高达90.00%,密云和顺义种群均为26.67%,浙江宁波种群为5.00%,而海南吉阳种群不存在该位点的突变。表明该CAPS标记还需与其它抗性机制或检测技术结合来实现叶螨对阿维菌素抗性的早期检测和预警。     

阿维菌素在3种十字花科蔬菜中的残留消解动态

为探明阿维菌素在十字花科蔬菜芥蓝、叶芥菜和芜菁中的残留消解行为和安全性,建立了高效液相色谱测定3种蔬菜中阿维菌素残留量的分析方法。样品经丙酮提取,C18柱净化,高效液相色谱-紫外检测器检测,外标法定量;运用所建立的方法对阿维菌素在山东烟台、河北保定、浙江绍兴、贵州贵阳、黑龙江哈尔滨和安徽宿州6个试验点的芥蓝、叶芥菜、芜菁中的残留消解动态和最终残留量进行了研究。结果表明:阿维菌素在芥蓝、叶芥菜和芜菁中的消解速率很快,半衰期分别为0.3~0.6、2.2~3.1和0.8~1.0 d,其残留量随时间延长而递减,符合一级反应动力学方程,属易消解型农药。     

Fitness costs associated with milbemectin resistance in the two-spotted spider mite Tetranychus urticae

The two-spotted spider mite Tetranychus urticae Koch is one of the most important pests of a wide range of crops worldwide. Its control is still largely based on the use of acaricides. However, due to its short life-cycle, high fecundity and arrhenotokous reproduction, it is able to develop resistance to these compounds very rapidly. Preliminary studies for milbemectin resistance in T. urticae showed that, under laboratory conditions, such resistance was unstable in the absence of a selection pressure. The aim of this study was to evaluate the possible fitness costs associated with milbemectin resistance in T. urticae. Comparison of biological traits between resistant and susceptible strains indicated the occurrence of fitness costs associated with milbemectin resistance. The resistant strain showed a longer juvenile development period for females, lower fecundity and a higher proportion of males among the progeny. The figures for net reproductive rate (R ₀), intrinsic rate of natural increase (r _m) and finite rate of increase (λ) were higher in the susceptible strain. The instability of milbemectin resistance can be exploited in resistance management programmes.     

溴甲烷熏蒸对山楂叶螨和桃蛀果蛾的毒力研究

苹果是我国的重要出口水果,山楂叶螨(Tetranychus viennensis Zacher)和桃蛀果蛾(Carposinasasakii Matsumura)在苹果主产区广泛分布,严重威胁我国苹果出口。为确定溴甲烷检疫处理山楂叶螨和桃蛀果蛾的技术指标,本文系统测定了一系列温度条件下溴甲烷对山楂叶螨成螨和富士苹果中桃蛀果蛾老熟幼虫的毒力,确定在5℃、10℃、15℃、20℃和25℃下,溴甲烷熏蒸山楂叶螨死亡率达到机率值9所需浓度时间乘积(CT值)分别为126.66、84.35、59.15、45.23和40.33mg.h/L,溴甲烷熏蒸桃蛀果蛾死亡率达到机率值9所需CT值分别为128.05、81.80、52.91、41.56和36.43mg.h/L。根据上述结果,建议采用10.0～14.9℃40g/m3 2h、15.0～19.9℃32g/m3 2h、20.0～24.9℃24g/m3 2h和大于25.0℃20g/m3 2h作为出口苹果的溴甲烷熏蒸处理技术指标。     

Crude Bacillus thuringiensis pellets efficiently combats Eutetranychus orientalis,the spider mite

This study demonstrates the efficacy of the crude pellet of Bacillus thuringiensis subs. kurstaki (Btk) obtained by SmF or SSF to combat Eutetranychus orientalis Klein. For bioassay, the mites were collected from infested leaves of Vigna unguiculata and Moringa oleifera, and reared by leaf-disc method employing artificial feeding system. In terms of LC₅₀ values, the crude Btk-toxin (probit: 9.51 mg/mL) obtained by SSF was 2.2-fold more efficient in killing E. orientalis than that of SmF (probit: 22 mg/mL). For the efficacy trial with potted plants, 10 mg crude Btk-toxin obtained by SSF was directly sprayed on the infested plants (V. unguiculata), which completely eliminated the mites from the infested plants within 12 days of treatment. In comparison, the survival rate of mites which received Btk-toxin from SSF was significantly (P < 0.0001) lesser than those received Btk-toxin from SmF. In this first report, apart from the efficiency of Btk-toxin in solid-fermented matter to deter the mites without supplementing any adhesive or surfactant in the diet, a feeding system for its rearing in the laboratory coupled with bioassay was also demonstrated.     

Antibiosis of maize inbred lines to the carmine spider mite, tetranychus cinnabarinus

The antibiosis of tenZea mays L. inbred lines to the carmine spider mite,Tetranychus cinnabarinus (Boisduval) (Acari: Tetranychidae), was evaluated. Two maize inbred lines previously reported as resistant to this spider mite and a susceptible inbred line were compared with B96 (formerly called 41:2504B), reported as being resistant to the two-spotted spider mite T. urticae and to the European corn borer (Ostrinia nubilalis Hübner). Other lines were derived from B96. All lines originated in the U.S.A. and were tested in Israel at two different growth stages. Four days after inoculation of detached leaf squares with adult mites, significant differences in susceptibility were observed among lines. At the 3-leaf stage lines B68, B96, B79, A619, B65, B49 and B64 reduced the average mite daily fecundity by 43%, 64%, 66%, 67%, 77%, 81% and 87%, respectively, as compared with the most susceptible line, B52. At the flowering stage, the average reduction in mite daily fecundity was much lower: inbred lines B64, A619 and B96 reduced the average mite daily fecundity by 48%, 51% and 86%, respectively, whereas the seven other genotypes had an intermediate or a susceptible reaction to the carmine spider mite, with A661 being the most susceptible. Our results show that B96 could be used as a source of resistance in developing improved resistance of inbred lines of maize to carmine spider mites.     

5种杀虫剂和黄瓜新小绥螨对棉田朱砂叶螨的协调防治

为协调使用杀虫剂及害虫天敌,本文测定了阿维菌素、印楝素、苦参碱、除虫菊素和吡虫啉5种常用杀虫剂分别与天敌黄瓜新小绥螨(原名胡瓜钝绥螨)对棉田朱砂叶螨的联合防治效果。结果表明:1.8%阿维菌素EW(1∶8 000)处理6d后释放黄瓜新小绥螨对朱砂叶螨的防治效果最佳,20d后相对防治效果高达96.63%;其次是0.3%印楝素EC(1∶250)处理7d后释放黄瓜新小绥螨,1d和20d后防效分别为59.7%和90.16%;0.5%苦参碱AS(1∶2 000)处理6d后释放黄瓜新小绥螨,20d后相对防治效果达到82.65%。本研究为朱砂叶螨可持续防控提供了可选方案,为延缓抗药性产生提供了研究思路。     

仿生胶对枸杞瘿螨种群动态及空间分布型的影响

仿生胶已成为一项防控病虫害的新技术,本文研究了仿生胶对枸杞瘿螨种群动态及空间分布型的影响。种群动态研究表明:仿生胶处理对瘿螨的发生量有着很好的控制作用,与药剂处理和对照处理差异显著;应用几种聚集度指标的计算公式和Iwao、Taylor的回归方程式,分析和测定了3种处理瘿螨的空间分布格局,结果表明在采果期仿生胶处理阶段性地改变了瘿螨的空间分布型,为聚集分布,药剂处理和对照处理均为均匀分布。