棉铃虫对菊酯类药剂的抗性狭义遗传力

通过单对交配设计不同的交配家系,采用半同胞法分析了棉铃虫对三氟氯氰菊酯和氰戊菊酯的抗性狭义遗传力,并对2种菊酯类药剂的抗性发展速度进行评价。结果表明,棉铃虫对三氟氯氰菊酯和氰戊菊酯的抗性狭义遗传力分别为0.2476±0.0248和0.4625±0.1578,说明棉铃虫对氰戊菊酯的抗性发展速度要快于三氟氯氰菊酯。另外,通过方差分析发现,在棉铃虫对拟除虫菊酯类药剂的抗性遗传中,母体效应对其没有影响。     

萝卜蚜对氰戊菊酯的抗药性汰选及其交互抗性

将田间采回的萝卜蚜种群分成两部分,一部分用氰戊菊酯连续汰选13次,另一部分不用药汰选,连续饲养作对照。汰选前及每汰选3～4次测定1次氰戊菊酯对两种群的毒力。结果表明,对照种群对氰戊菊酯的敏感性增加3.76倍,而汰选种群对该农药的抗药性与汰选前比较增长了163.25倍,与同期饲养对照种群比较,抗性已达613.62。该汰选种群对不含氟的溴氰菊酯和氯氰菊酯存在明显的交互抗性(分别达360.7和53.9倍),对含氟的三氟氯氰菊酯、氟氰菊酯和氟胺氰菊酯也存在交互抗性,但只有7倍左右;而对马拉硫磷、氧化乐果、杀螟松、久效磷和灭多威及菊马混剂没有表现出交互抗性,为进一步探讨萝卜蚜的抗药性治理措施提供了试验依据。     

棉铃虫对溴氰菊酯、三氟氯氰菊酯及其复配剂的抗性趋势与交互抗性

在70％的高选择压下,分别用溴氰菊酯、三氟氯氰菊酯和凯明2号(50％辛硫磷·甲基对硫磷·三氟氯氰乳油,即含三氟氯氰菊酯的复配药剂)对室内饲养了12代未经农药处理的棉铃虫Helicoverpa armigera(H(?)bner)敏感品系进行了抗性筛选。结果,经连续筛选至第12代的LD_(50)值与筛选前第1代的LD_(50)值比较,抗溴氰菊酯种群对溴氰菊酯的抗性为136.7倍,属高抗水平;抗三氟氯氰菊酯种群对三氟氯氰菊酯的抗性为9.5倍,抗凯明2号种群对凯明2号的抗性为3.4倍,均属低抗水平。用8种常用杀虫剂分别对这3个种群在停止上述杀虫剂筛选2代后进行了交互抗性分析。结果表明,3个种群平均对8种杀虫剂的抗性倍数中,对溴氰菊酯、氰戊菊酯、灭多威的抗性极显著高于其余5种杀虫剂;3个种群的平均抗性倍数之间差异极显著,顺序依次为抗溴氰菊酯种群>抗三氟氯氰菊酯种群>抗凯明2号种群;以平均抗性倍数表示的抗性种群与杀虫剂的交互作用有以下几个结果:①高抗溴氰菊酯的种群对氰戊菊酯和灭多威有极显著的交互抗性,但对三氟氯氰菊酯和凯明2号仍反应敏感。②抗三氟氯氰菊酯和抗凯明2号的2个种群对溴氰菊酯有极显著的交互抗性;抗三氟氯氰菊酯种群对灭多威和氰戊菊酯有一定抗性,抗凯明2号种群对硫丹有一定抗性。     

马铃薯桃蚜对拟除虫菊酯类杀虫剂的敏感性及其体内羧酸酯酶活性研究

为明确内蒙古马铃薯主要种植区马铃薯桃蚜的抗药性水平及抗性形成机制,采用室内生物测定方法,检测了内蒙古呼和浩特市及呼和浩特武川县马铃薯桃蚜田间种群(分别简称为呼市种群和武川种群)和室内饲养未接触任何药剂的马铃薯桃蚜敏感种群对7种拟除虫菊酯类杀虫剂的敏感性,并对供试各种群桃蚜的羧酸酯酶(CarE)活性进行了研究。结果表明:相对于敏感种群,呼市种群和武川种群对氯氰菊酯均产生了高水平抗性(抗性倍数为74.11和549.4);呼市种群对联苯菊酯产生了中等水平抗性(16.03倍),对氰戊菊酯、高效氯氰菊酯和高效氯氟氰菊酯仍保持敏感(1.00~4.00倍);武川种群对溴氰菊酯(10.14倍)、甲氰菊酯(26.46倍)和联苯菊酯(33.74倍)处于中等抗性水平,对高效氯氰菊酯、氰戊菊酯和高效氯氟氰菊酯仍较为敏感(50值分别为0.54、1.07和0.93 nmol/L。三唑磷分别与高效氯氰菊酯和溴氰菊酯联用可显著增强其毒力,表明三唑磷与这两种拟除虫菊酯类药剂复配在武川和呼市马铃薯桃蚜防治中具有很好的应用潜力。     

拟除虫菊酯抗性

背景资料 1983年初,人们确证棉铃虫(Heliothis armigera)对合成拟除虫菊酯:氰戊菊酯(fenvalerate)、氯氰菊酯(cypermethrin)、溴氰菊酯(deltamethrin)和二氯苯醚菊酯(permethrin)已产生抗性。在埃默拉尔德首次发现抗性,那里由于拟除虫菊酯在棉花、高粱和大豆上使用无效,而使产量大减。在生长季节的后期,在新南威尔士和昆士兰(莫里、纳拉布瑞、沃伦乔治州)的其它一些棉区,也发现了低于中等水平的抗性。在前两     

甜菜夜蛾对三种拟除虫菊酯杀虫剂的抗性稳定性研究

在室内脱离药剂选择的条件下,分别研究了甜菜夜蛾Spodoptera exigua Hübner 对氯氟氰菊酯、氰戊菊酯和顺式氯氰菊酯3种拟除虫菊酯杀虫剂的抗性稳定性及抗性衰退规律。结果表明,即使甜菜夜蛾对氯氟氰菊酯、氰戊 菊酯、顺式氯氰菊酯的抗性分别达522.9倍、669.7倍和2 737.2倍,抗性仍不稳定,分别经10代、8代和9代饲养后抗性下降为60.8倍、90.8倍和180.5倍;对田间抗性种群的抗性衰退研究发现,甜菜夜蛾对这3种拟除虫菊酯的抗性也表现为不稳定性,在无杀虫剂选择的情况下,开始几代抗性下降较快,当下降至一定水平(6~10倍)后,抗性趋于基本稳定,但很难完全恢复对拟除虫菊酯的敏感性。     

环渤海湾地区棉铃虫的抗药性水平及成因分析

１９９４～１９９７年测定了环渤海湾地区１６个点２６个棉铃虫种群对三氟氯氰菊酯、辛硫磷和硫丹的抗性水平。对三氟氯氰菊酯的抗性为６５．４３～４４２倍,对辛硫磷的抗性为１０．２８～９０．９３倍,对硫丹的抗性为６．３４～２９．１７倍,地区之间年度内总体上差异不大。对采自辽宁省辽阳市种群的抗性稳定性研究表明,解除农药选择压后棉铃虫的抗药性下降较快,１７代后对三氟氯氰菊酯、辛硫磷和硫丹的抗生水平由２１３．７１     

小菜蛾对阿维菌素的敏感度及抗性现实遗传力的分析

不同地区小菜蛾对阿维菌素的敏感度及其抗性现实遗传力的研究结果表明,宣化种群和武汉种群对阿维菌素的LC50仅是敏感品系的3郾7、5郾7倍,未产生明显抗性;北京种群和云南种群LC50分别是敏感品系的15郾7、22郾3倍。阿维菌素对小菜蛾抗性选育的21代和27代,分别估算抗性现实遗传力为0郾12。假设田间种群的抗性现实遗传力为室内选育估算值的50%,AVMs对小菜蛾的杀死率分别为50%、70%、80%和90%,则预计抗性增长到10倍时,AVMs可使用的次数分别为17次、12次、10次和8次。     

防治棉铃虫的高毒农药替代品种研究

采用室内浸卵、浸叶和点滴法以及田间小区试验,对19种杀虫剂防治棉铃虫的作用特点和效果进行了系统研究。室内生物测定结果表明:多杀菌素对棉铃虫卵孵化有较好的抑制作用,90.40 mg/L多杀菌素处理后棉铃虫卵的孵化率仅为42.86%;多杀菌素、甲氨基阿维菌素、高效氯氟氰菊酯、辛硫磷、丙溴磷、毒死蜱和高效氯氰菊酯对棉铃虫初孵幼虫的毒杀作用明显,原药稀释1.0×104~2.0×104倍时可使初孵幼虫死亡率达100%;昆虫生长调节剂——氟啶脲、氟铃脲、甲氧虫酰肼原药稀释1 000倍对棉铃虫初孵幼虫的致死率大于70％,且幼虫的生长受到明显抑制;甲氨基阿维菌素、高效氯氟氰菊酯、多杀菌素、毒死蜱、高效氯氰菊酯、丙溴磷、辛硫磷对低、高龄棉铃虫幼虫均具有较好的毒杀效果。田间小区试验结果表明,甲氨基阿维菌素、高效氯氟氰菊酯、丙溴磷、高效氯氰菊酯作用效果快且防治效果好,尤其是4 000倍甲氨基阿维菌素和5 000倍高效氯氟氰菊酯处理后第三天,其对棉铃虫的致死率达100％;多杀菌素和甲氧虫酰肼作用效果稍差。若在棉铃虫卵高峰期适时施药,供试的6种药剂均可作为防治棉铃虫的高毒农药替代品种。     

单对汰选方法在加速抗高效氯氟氰菊酯棉铃虫品系汰选中的应用

通过设计杂合种群单对杂交方式,研究了加速获得抗性品系的方法。以高效氯氟氰菊酯群体汰选后抗性倍数为4.9倍的棉铃虫种群及其同源对照种群为材料,同时设置常规群体汰选方法与单对汰选方法,研究单对汰选方法在加速抗高效氯氟氰菊酯棉铃虫品系汰选中的作用。结果表明,群体汰选两代后抗性倍数由4.9倍提高到7.4倍, 而单对汰选两代后抗性倍数由4.9倍提高到27.3倍。表明在常规群体汰选中穿插几代单对汰选方法可明显加快棉铃虫种群对高效氯氟氰菊酯的抗性汰选进程。     

Efficacy of various pyrethroid structures against a highly metabolically resistant isogenic strain of Helicoverpa armigera (Lepidoptera: Noctuidae) from China

BACKGROUND: Resistance to pyrethroids and other types of insecticides in Helicoverpa armigera (Hübner) has been documented in many countries. The isolation of specific resistance mechanisms in isogenic strains is an optimal approach to investigate cross-resistance pattern, and to validate resistance breaking pyrethroids. In this study an isogenic metabolic resistance CMR strain was successfully isolated from a field pyrethroid-resistant population of H. armigera. With this strain, cross-resistance among 19 pyrethroid insecticides with varying chemical structures was analysed. RESULTS: Resistance to pyrethroids in the CMR strain was likely to be due to enhanced oxidative metabolism. The most significant cross-resistance in the CMR strain was between pyrethroids such as fenvalerate, tau-fluvalinate and flumethrin characterised by having both phenoxybenzyl and aromatic acid moieties. Substitution of the phenoxybenzyl group with a polyfluorobenzyl group, as in tefluthrin, benfluthrin and transfluthrin, overcame most of this resistance. CONCLUSION: The findings in this study support the assertion that it is possible to find pyrethroids that are active against resistant populations. Such pyrethroids could be considered as possible partners or resistance breaking pyrethroids in a pyrethroid resistance management programme for H. armigera in China and in other Asian countries where the oxidative metabolism resistance is a dominant mechanism.     

棉铃虫对拟除虫菊酯农药的抗性治理效果评价

作者在河北省定州市600hm~2棉田设立了棉铃虫抗药性治理示范区,采取以降低农药的选择压和利用敏感个体的稀释作用为出发点的一系列措施,实施了抗性治理。为评价治理效果,1991～1995年连续监测了河北省3个地区棉铃虫对氰戊菊酯、溴氰菊酯、氯氰菊酯和三氟氯氰菊酯的抗药性水平。结果表明,在非治理区,固安县种群的抗性指数(RR)由1991年的9.8～15.5倍,上升到1995年的26.1～85.3倍;故城县种群由31.1～57.7倍,上升到90.7～155.4倍;而抗性治理区定州市种群的抗性发展却较缓慢,稳定保持在18.0～25.0倍之间的中抗水平,证明抗性发展得到了有效控制。与非抗性治理区比较,定州棉田棉铃虫的虫口数下降4～8倍、防治费用降低23.7％～50％、纯收入增加约40％,说明抗性综合治理获得了初步的成功。     

新疆与华北棉区棉铃虫对氯氟氰菊酯kdr型抗性频率比较

通过单对杂交结合热探针法 ,研究比较了新疆与华北棉区田间种群棉铃虫对氯氟氰菊酯 kdr型抗性个体频率、抗性基因型频率和抗性基因频率的差异。结果表明 :新疆种群、河北冀州种群和河南西华种群的 kdr型抗性个体频率分别为 1.0 0 %、2 8.4 3%、2 4 .4 3% ;新疆XF1种群、冀州 JF1、JF2 种群的 kdr型抗性基因频率分别为 0、2 0 .83%、11.11%。分别从群体与个体水平上说明了新疆棉铃虫对菊酯类农药尚处于敏感阶段 ,而华北种群 kdr型抗性已达较高水平 ,并且抗性个体主要以杂合子形式存在。     

Selection and heritability of resistance to Bacillus thuringiensis subsp kurstaki and transgenic cotton in Helicoverpa armigera (Lepidoptera: Noctuidae)

Compared with an unselected susceptible population, a cotton bollworm, Helicoverpa armigera (Hübner), population selected for 22 generations with transgenic cotton leaves (modified Cry1A) in the laboratory developed 11.0-fold resistance to Cry1Ac (one single-protein product MVPII). Resistance to Bacillus thuringiensis Berliner subsp kurstaki (Btk) was selected for 22 generations with a 5.2-fold increase in LC50. The estimated realized heritabilities (h2) of resistance for transgenic-cotton- and Btk-selected populations were 0.1008 and 0.2341, respectively. This reflects the higher phenotypic variation in response to Cry1Ac in the transgenic-cotton-selected population. This variation may have been caused by differences in protein toxin levels expressed in different growth stages of the transgenic cotton. Because of the different slopes of the probit regression lines between Cry1Ac and Btk, the estimated realized h2 cannot be used visually to compare resistance development to Cry1Ac and Btk in H armigera. Thus, the response quotient (Q) of resistance was also estimated. The Q values of resistance for transgenic-cotton- and Btk-selected populations were 0.0763 and 0.0836, respectively. This showed that the rate of resistance development would be similar in both selection populations. This result indicates that the selection of resistance using transgenic cotton is different from that selected using the single toxin. Resistance risk to transgenic cotton and Btk in field populations was assessed assuming different pressures of selection by using the estimated h2. Assuming the h2 of resistance in a field population was half of the estimated h2, and the population received prolonged and uniform exposure to transgenic cotton or Btk causing >70% mortality in each generation, we predicted that resistance would increase 10-fold after <23 generations for Cry1Ac in transgenic cotton-selected-populations and after <21 generations for Btk in Btk-selected populations. Cross-resistance would be expected after <48 generations for Btk in transgenic-cotton-selected populations and after <21 generations for Cry1Ac in Btk-selected population. The results show that the potential to evolve resistance is similar in both transgenic-cotton- and Btk-selected populations, but that cross-resistance development to Btk is slower in transgenic-cotton-selected populations than cross-resistance development to Cry1Ac in Btk-selected populations.     

不同生境的草间钻头蛛种群对拟除虫菊酯类杀虫剂的敏感性及体内解毒酶活性的测定

采用浸渍法测定了不同生境的草间钻头蛛Hylyphantes graminicola种群对氰戊菊酯、溴氰菊酯和氯氰菊酯的敏感性,并对其体内的酯酶、多功能氧化酶-O-脱甲基和谷胱甘肽-S-转移酶的活性进行了测定。结果表明,不同生境的草间钻头蛛种群对3种拟除虫菊酯杀虫剂的敏感水平不同:草丛种群最为敏感;棉田种群的抗药性最强,其中对氰戊菊酯的抗药性最高,相对抗性指数为14.61,达到中抗水平;其他种群对3种杀虫剂较敏感或抗性较低。5种生境草间钻头蛛体内的酯酶、多功能氧化酶-O-脱甲基和谷胱甘肽-S-转移酶的活性均以草丛种群最低,棉田种群最高。酯酶和多功能氧化酶-O-脱甲基活性的增强可能是棉田草间钻头蛛种群对拟除虫菊酯类杀虫剂不敏感或产生抗性的原因。     

棉铃虫抗药性基因流动对抗性频率的影响

通过设计不同的迁移比例（1％、5％、10％、20％）,研究棉铃虫抗药性基因流动对三氟氯氰菊酯和氰戊菊酯抗性频率的影响。结果表明,抗性个体迁入敏感种群,使得敏感种群抗生频率增加,迁移比例越大,抗性频率增加越大;而敏感个体迁入抗生种群使得其抗性频率减少,随着敏感个体迁入比例的增大,抗性种群中抗性频率的减少量越大。利用抗性频率变化值与相应迁移率的比值来表示迁移的相对效率,结果表明迁移率为1％时,迁移影响抗性个体频率变化的相对效率最高。