南京地区小菜蛾对常用杀虫剂抗药性的动态监测

分别于1997、1998、2001、2002年就南京地区,小菜蛾对溴氰菊酯、高效氯氰菊酯、敌敌畏、杀虫单、氟啶脲、氟虫腈、阿维菌素7种杀虫剂的抗药性,进行了动态监测。抗性测定结果表明,与敏感种群相比,南京地区小菜蛾对溴氰菊酯的抗性水平,1998年最高为283．81倍,表现为极高水平的抗性,2001～2002年抗药性呈下降趋势。小菜蛾对高效氯氰菊酯的抗性指数82．13～142．48倍,为高水平抗性。对敌敌畏的抗性指数10．10～14．81倍,为中等水平的抗性,并有逐年缓慢下降趋势。对杀虫单和阿维菌素的抗性指数小于5,1998年后敏感性开始下降。对氟啶脲和氟虫腈仍处于敏感至敏感性下降阶段,2001～2002年抗性指数呈下降趋势。除杀虫单外,小菜蛾对供试的其余6种药剂的抗性倍数与抗性个体频率具有明显的相关性。     

北京和河北地区小菜蛾的抗药性动态

【目的】了解北京和河北地区小菜蛾Plutella xylostella(L.)对主要防治药剂的抗药性现状,为小菜蛾的有效防治提供参考。【方法】2011—2015年,采用浸叶法监测了小菜蛾对9种药剂的抗药性。【结果】小菜蛾对氯虫苯甲酰胺、多杀菌素和丁醚脲均为敏感水平,对Bt制剂、虫螨腈和茚虫威个别年份出现中等抗性水平,但总体上为敏感状态,对阿维菌素和氟啶脲保持中等抗性水平,对高效氯氰菊酯为中等至高水平抗性。【结论】在北京和河北地区高效氯氰菊酯不适用于小菜蛾的防治,少用或暂停使用阿维菌素,其它药剂可交替或轮换使用。     

高效氯氰菊酯对小菜蛾阿维菌素抗性、敏感种群的亚致死效应

在实验室条件下研究了高效氯氰菊酯亚致死剂量LC10 (43.44 mg/L)(小菜蛾阿维菌素抗性种群)和LC10( 12.61 mg/L)(敏感种群)对小菜蛾阿维菌素抗性(AV - R)、敏感(AV -S)种群的亚致死效应.结果表明:高效氯氰菊酯亚致死剂量12.61 mg/L处理小菜蛾阿维菌素敏感、抗性种群3龄幼虫后,...     

家蝇（Musca domestica）对三氟氯氰菊酯的抗药性遗传

研究了家蝇对三氟氯氰菊酯抗性的遗传,通过对抗性品系和敏感品系杂交后代的抗性遗传分析发现家蝇对三氟氯氰菊酯的抗性受多因子控制,抗性显性率为－0．102,为不完全隐性。其对三氟氯氰菊酯的抗性现实遗传力为0．120。     

小菜蛾对九种杀虫剂的抗药性

采用叶片药膜法测定了9种杀虫剂对海南、山东、广东、湖北武汉和襄樊等5个地区小菜蛾Plutella xylostella(L.)田间种群的毒力,和室内相对敏感品系比较。结果显示,5个地区的小菜蛾种群都对氯氰菊酯产生了10倍以上的抗性,广东和山东种群达到30倍以上的抗性。对阿维菌素的抗性山东小菜蛾种群达到135倍,广东种群达到30倍,其他地区均在10倍以下。但是,作用机制与阿维菌素类似的药剂,氟虫腈的抗性5个地区均在5倍或5倍以下。对昆虫生长调节剂定虫隆和氟虫脲的抗性除广东种群分别在10倍和20倍以上外,其他地区均在5倍以下。广东种群对多杀菌素的抗性为7.8倍,其他地区的种群没有产生抗性,多杀菌素和杀虫双均为作用于乙酰胆碱受体的药剂,但是作用的位点不同。杀虫双对5个种群的LC50值均是比较大的(>800 mg/L),尽管没有明显的抗性,不适宜用于小菜蛾田间防治。对呼吸链电子转移抑制剂溴虫腈的抗性均在10倍以下。对辛硫磷的抗性在2~5倍。     

高原春油菜田小菜蛾种群动态和抗药性的监测

【目的】为了准确掌握典型春油菜种植区小菜蛾Plutella xylostella(L.)种群变化动态和抗药性现状。【方法】诱捕法调查了青海高原小菜蛾成虫发生动态、室内用浸渍法测定了小菜蛾田间种群的抗性倍数,并进行了田间药效试验。【结果】青海省小菜蛾一般一年发生3代,但2 500 m以上的地区第3代成虫数量较第1代、第2代明显下降。在我省高原春油菜区,每日20:00至次日晨4:00是小菜蛾成虫发生主要的时间段。小菜蛾在青海省不能越冬。湟中点小菜蛾对溴虫腈产生低水平抗性;对多杀菌素、丁醚脲产生中等抗性水平;对Bt、高效氯氰菊酯、茚虫威产生高水平的抗性;对阿维菌素、啶虫隆、氯虫苯甲酰胺产生极高水平抗性。互助点小菜蛾对溴虫腈、丁醚脲产生低水平抗性;对多杀菌素、啶虫隆产生中等抗性水平;对Bt、氯虫苯甲酰胺、茚虫威产生高水平抗性;对阿维菌素产生极高水平抗性。小菜蛾的抗性监测结果与田间药效结果基本一致,溴虫腈的抗性倍数最低,田间防治效果好于其他参试药剂。【结论】青海省小菜蛾年发生代数较少,且不能越冬。春油菜田小菜蛾已对大部分农药产生了抗药性。     

内蒙古小菜蛾种群数量动态及抗药性监测

2009—2011年对内蒙古呼和浩特市郊区十字花科蔬菜和武川县油菜上小菜蛾Plutella xylostella(L.)种群消长动态进行了调查,并比较了呼和浩特地区小菜蛾对11种杀虫剂的抗药性。结果表明,在呼和浩特郊区,小菜蛾成虫于4月上旬开始出现,一年中有4个发生高峰,分别为4月下旬或5月上旬、6月中旬、8月下旬和10月上旬;小菜蛾幼虫在春甘蓝和秋白菜整个生长期间均有发生,大约有4个发生高峰,分别为6月上中旬、6月下旬或7月上旬、9月上旬和10月上旬。在武川县,小菜蛾成虫于4月末或5月初开始发生,春夏季数量高于秋季,共有2个发生高峰,2009年为5月下旬和6月中旬,2010年为6月上旬和8月上中旬;小菜蛾幼虫在6月下旬开始出现,在油菜整个生长期间,小菜蛾幼虫约有3个数量高峰,分别为7月初、7月末和8月下旬,秋季数量高于春夏季。在供试的11种杀虫剂中,溴虫腈对小菜蛾幼虫的毒力最高,LC50为0.22 mg·L-1;其次为多杀菌素、氯虫苯甲酰胺、氟虫腈和BT,LC50分别为0.82⁰.83、1.09、1.36和3.41 mg·L-1;再次为茚虫威和阿维菌素,LC50分别为15.74 mg·L-1和6.030.83、1.09、1.36和3.41 mg·L-1;再次为茚虫威和阿维菌素,LC50分别为15.74 mg·L-1和6.03²3.47 mg·L-1;然后为丁醚尿、虫酰肼和啶虫隆,LC50分别为51.30、52.66和61.91 mg·L-1;最低为高效氯氰菊酯,LC50为462.6623.47 mg·L-1;然后为丁醚尿、虫酰肼和啶虫隆,LC50分别为51.30、52.66和61.91 mg·L-1;最低为高效氯氰菊酯,LC50为462.66⁶73.26 mg·L-1。抗药性测定表明,呼和浩特地区小菜蛾幼虫未对溴虫腈、虫酰肼、氯虫苯甲酰胺和丁醚尿产生抗性,对多杀菌素和氟虫腈为低抗性,对茚虫威和BT为中抗性,对高效氯氰菊酯、啶虫隆和阿维菌素为极高抗性。     

氰氟虫腙对小菜蛾阿维菌素抗性和敏感种群的亚致死效应(英文)

在实验室条件下采用生命表技术研究了氰氟虫腙亚致死剂量（LC₂₅）对小菜蛾Plutella xylostella阿维菌素抗性（AV-R）和敏感（AV-S）种群的亚致死效应, 旨在为小菜蛾对阿维菌素的抗性治理提供理论基础。结果表明： 氰氟虫腙对小菜蛾3龄幼虫抗性种群的LC₅₀和LC₂₅分别为0.24 mg/L和0.09 mg/L; 对敏感种群的LC₅₀和LC₂₅分别为0.20 mg/L和0.07 mg/L。氰氟虫腙亚致死剂量0.09 mg/L 处理小菜蛾后, 对处理代的影响表现为显著降低处理种群的化蛹率、 蛹重、 羽化率、 繁殖力; 明显延长蛹期, 缩短成虫产卵期和寿命; 对子代种群的影响表现为显著降低卵的孵化率、 幼虫各龄期的存活率, 延长发育历期。处理种群的内禀增长率（r_m）、 周限增长率（λ）和净增值率（R₀）显著低于对照种群（P<0.0001）。亚致死剂量的氰氟虫腙对小菜蛾抗性种群的影响大于敏感种群, 对处理代种群的影响大于子代种群。氰氟虫腙亚致死剂量可以极大地影响小菜蛾尤其是阿维菌素抗性种群的种群动态, 因此氰氟虫腙对于小菜蛾的抗性治理具有积极的作用。     

小菜蛾对菊酯类农药抗性水平及高效农药应用研究

室内试验彩和叶片浸渍法,对江苏五个地区的小菜蛾进行毒力及抗性测定比较。结果表明江苏南京、扬州等菜区小菜蛾对三种拟除虫菊酯已产生高抗水平的抗性,抗性倍数74．03－324．13。小菜蛾对溴氟菊酯、氰戊菊酯、DDVP、快灵表现不同程度的交互抗性;对杀虫双、氟铃脲、宝路不产生交互抗性;对锐劲特、灭虫灵为负交互抗性。筛选出高效、低毒、无公害的单剂6个,复配剂3个。灭虫灵、锐劲特、氟铃脲、抑太保、宝路、杀虫双对小菜蛾具有很高的活性,LC50为0．018－71．83ppm。田间试验结果,灭虫灵8ppm防效95％以上,持效期10天;氟铃脲50ppm,前期药效表现慢,7－10天达90％以上。三个复配剂中以灭虫灵与高效氯氰菊酯复配药效与速效表现突出,10ppm12－15天药效95％以上,其它两个复配剂见效较慢,5－10天的防效90％以上。     

小菜蛾对三氟甲吡醚的抗性风险评价与抗性生化机制研究

【目的】明确小菜蛾Plutella xylostella(Linnaeus)对三氟甲吡醚的抗性风险和抗性生化机制,为三氟甲吡醚的合理使用提供科学依据。【方法】采用TabashnikMc Gaughey的阈性状分析方法评估小菜蛾对三氟甲吡醚的抗性风险;采用浸叶法测定增效剂(胡椒基丁醚、磷酸三苯酯和顺丁烯二酸二乙酯)对三氟甲吡醚的增效作用,通过酶动力学方法测定了小菜蛾对三氟甲吡醚抗性和敏感品系的谷胱甘肽-S-转移酶、酯酶和多功能氧化酶的活性。【结果】经过18代次筛选,小菜蛾种群对三氟甲吡醚的抗性水平上升至14.8倍,小菜蛾对三氟甲吡醚的抗性现实遗传力(h~2)为0.1558;当h~2=0.155 8时,在致死率为50%-90%的选择压力下,预计小菜蛾对三氟甲吡醚抗性增加10倍分别需要16.1-7.3代。在小菜蛾三氟甲吡醚抗性品系中,酯酶和多功能氧化酶比活力均显著高于敏感品系,分别为敏感品系的1.34倍和1.45倍;谷胱甘肽-S-转移酶比活力与敏感品系的无显著差异。抗性品系的酯酶抑制剂磷酸三苯酯和多功能氧化酶抑制剂胡椒基丁醚对三氟甲吡醚具有明显增效作用,增效倍数分别为1.21倍和1.43倍;谷胱甘肽-S-转移酶抑制剂顺丁烯二酸二乙酯对三氟甲吡醚没有明显增效作用。【结论】小菜蛾对三氟甲吡醚产生抗性的风险较大,酯酶和多功能氧化酶活性的升高可能是小菜蛾对三氟甲吡醚产生抗性的重要机制。     

Insecticide resistance in populations of the diamondback moth, Plutella xylostella (L.) (Lepidoptera: Plutellidae), from the state of Pernambuco, Brazil

The diamondback moth Plutella xylostella (L.) has a great economic importance in Brassicaceae crops in many parts of the world. Recurrent infestations of this pest in growing areas of Pernambuco state, Brazil, have led farmers to frequently spray their crops with insecticides. However, control failures by several insecticides have been alleged by farmers. The objective of this study was to check whether resistance to insecticides could explain these control failures in P. xylostella. Populations of P. xylostella from Pernambuco were collected between January and April 2009. The resistance ratios of P. xylostella populations were compared among five different active ingredients: abamectin, methomyl, lufenuron, indoxacarb, and diafenthiuron by leaf dipping bioassays using foliar discs of kale leaves. Mortality data were submitted to probit analysis. The P. xylostella populations showed variable response and significant resistance to one or more insecticides. The population from Bezerros County exhibited the highest resistance ratios to indoxacarb (25.3 times), abamectin (61.7 times), and lufenuron (705.2 times), when compared to the reference population. The populations from Bonito and Jupi Counties were 33.0 and 12.0 times more resistant to lufenuron and abamectin, respectively, when compared with the reference population. Resistance to methomyl was the least common, but not less important, in at least four populations. These results indicated that control failures were associated with resistance by some of the evaluated insecticides, reinforcing the need for resistance management in areas of the state of Pernambuco.     

滇西菜区小菜蛾发生规律及抗药性监测

掌握滇西菜区小菜蛾Plutella xylostella种群发生规律和抗药性水平,对提出区域性防控策略具有重要意义。2009-2015年,采用诱集法和浸叶法监测了滇西菜区小菜蛾种群发生动态及其对常用杀虫剂的抗药性。结果表明：滇西菜区小菜蛾全年发生,为害期有9个月,春夏季为害重,3-6月为发生高峰期,2009-2015年最高诱蛾量为290~905头/7 d,小菜蛾种群对化学杀虫剂均产生了不同水平的抗药性,其中对阿维菌素和高效氯氰菊酯的抗药性最高,达到高水平抗药性,对多杀菌素、茚虫威和溴虫腈维持在中等水平抗药性,2011年对氯虫苯甲酰胺产生了28倍的抗药性,后恢复敏感,3年后又出现抗药性的上升趋势。可见,3-6月是滇西菜区小菜蛾防控的重要时期,可选择Bt、多杀菌素、茚虫威和溴虫腈等药剂轮换使用,减少氯虫苯甲酰胺使用次数,建议停用阿维菌素和高效氯氰菊酯。     

小菜蛾抑制性谷氨酸受体的RNA干扰

谷氨酸门控的氯离子通道（glutamate-gated chloride channels, GluCls）或抑制性谷氨酸受体（inhibitory glutamate receptor, IGluR）是阿维菌素类药剂（avermectins）主要的作用靶标, 目前人们对于昆虫的IGluR知之甚少。本实验采用RNA干扰（RNAi）技术对小菜蛾Plutella xylostella IGluR的功能进行了初步研究。结果表明： 小菜蛾2龄和3龄幼虫中双链RNA（dsRNA）的最佳注射量分别为50.6 nL和71.3 nL。实时荧光定量（quantitative real-time PCR, qRT-PCR）检测结果表明, 2龄和3龄幼虫在注射dsRNA 36 h和24 h后IGluR基因的转录后水平分别下降了32.67%和49.30%。幼虫发生RNA干扰后对阿维菌素的敏感性结果显示, 注射了IGluR dsRNA的幼虫死亡率显著低于对照。结果说明, 小菜蛾IGluR是阿维菌素的潜在靶标之一, 为进一步阐明小菜蛾对阿维菌素靶标抗性机理奠定了基础。     

Host plant preference and the influence of different cabbage cultivars on the toxicity of abamectin and cypermethrin against Plutella xylostella Lepidoptera: Plutellidae

The toxicity of avermectin B, (abamectin) and cypermethrin was determined against fourth instar larvae of Plutella xylostella L. reared on three cabbage cultivars which differed in their suitability as host plants. Cabbage cultivars were assessed as hosts for P. xylostella on the basis of larval and pupal weight and adult fecundity. Larvae reared on the best host, the cabbage cv. Offenham Flower of Spring were significantly (P > 0.01) less sensitive to topically-applied abamectin (4.7-fold at LD₅₀) or cypermethrin (2.3-fold) when compared with larvae reared on the intermediate host, the Savoy cabbage cv. Aquarius F1. Larvae reared on Offenham Flower of Spring were also significantly (P > 0.01) less sensitive (4.5-fold) to topically-applied abamectin compared with larvae reared on the poorest host tested, the cabbage cv. Minicole Fl. In contrast, the residual/ingestion toxicity of abamectin against fourth instars was significantly (P > 0.01) greater (2.5-fold at LC₅₀) on Offenham Flower of Spring than on Minicole F1. The results are discussed in terms of larval weight and larval feeding rates on the different cabbage cultivars.     

The expression of Spodoptera exigua P450 and UGT genes: tissue specificity and response to insecticides

Cytochrome P450 and UDP-glucosyltransferase (UGT) as phase I and phase II metabolism enzymes, respectively, play vital roles in the breakdown of endobiotics and xenobiotics. Insects can in crease the expression of detoxificatio n enzymes to cope with the stress from xenobiotics including insecticides. However, the molecular mechanisms for insecticide detoxification in Spodoptera exigua remain elusive, and the genes conferring insecticide metabolisms in this species are less well reported. In this study, 68 P450 and 32 UGT genes were identified. Phylogenetic analysis showed gene expansions in CYP3 and CYP4 clans of P450 genes and UGT33 family of this pest. P450 and UGT genes exhibited specific tissue expression patterns. Insecticide treatments in fat body cells of S. exigua revealed that the expression levels of P450 and UGT genes were significantly influenced by challenges of abamectin, lambda-cyhalothrin, chlorantraniliprole, metaflumizone and indoxacarb. Multiple genes for detoxification were affected in expression levels after insecticide exposures. The results demonstrated that lambda-cyhalothrin, chlorantraniliprole, metaflumizone and indoxacarb induced similar responses in the expression of P450 and UGT genes in fat body cells;eight P450 genes and four UGT genes were co-up-regulated significantly, and no or only a few CYP/UGT genes were down-regulated significantly by these four insecticides. However, abamectin triggered a distinct response for P450 and UGT gene expression;more P450 and UGT genes were down-regulated by abamectin than by the other four compounds. In con elusion, P450 and UGT genes from S. exigua were identified, and different responses to abamectin suggest a different mechanism for insecticide detoxification.     

药剂喷施饵木防治双条杉天牛成虫的试验

2007年3月在室内进行药效筛选试验,结果表明,阿维·毒、毒死蜱、高效氯氟氰菊酯3种药剂喷施侧柏饵木均能杀死双条杉天牛成虫,毒死蜱作用最快,5d完全死亡率达到94.7%。2008年3月选用高效氯氰菊酯、阿维菌素·毒死蜱、丙溴磷进行了野外试验,结果表明,3种不同药剂防治效果差异显著,同种药剂不同浓度之间防治效果差异不显著,高效氯氰菊酯2000倍液效果最好。喷施高效氯氰菊酯、阿维菌素·毒死蜱不影响饵木的诱集效果。丙溴磷对饵木引诱效果产生影响,其机制机值得得进一步探讨。     

Mutations on M3 helix of Plutella xylostella glutamate-gated chloride channel confer unequal resistance to abamectin by two different mechanisms

Abamectin is one of the most widely used avermectins for agricultural pests control, but the emergence of resistance around the world is proving a major threat to its sustained application. Abamectin acts by directly activating glutamate-gated chloride channels (GluCls) and modulating other Cys-loop ion channels. To date, three mutations occurring in the transmembrane domain of arthropod GluCls are associated with target-site resistance to abamectin: A309V in Plutella xylostella GluCl (PxGluCl), G323D in Tetranychus urticae GluCl1 (TuGluCl1) and G326E in TuGluCl3. To compare the effects of these mutations in a single system, A309V/I/G and G315E (corresponding to G323 in TuGluCl1 and G326 in TuGluCl3) substitutions were introduced individually into the PxGluCl channel. Functional analysis using Xenopus oocytes showed that the A309V and G315E mutations reduced the sensitivity to abamectin by 4.8- and 493-fold, respectively. In contrast, the substitutions A309I/G show no significant effects on the response to abamectin. Interestingly, the A309I substitution increased the channel sensitivity to glutamate by one order of magnitude (∼12-fold). Analysis of PxGluCl homology models indicates that the G315E mutation interferes with abamectin binding through a steric hindrance mechanism. In contrast, the structural consequences of the A309 mutations are not so clear and an allosteric modification of the binding site is the most likely mechanism. Overall the results show that both A309V and G315E mutations may contribute to target-site resistance to abamectin and may be important for the future prediction and monitoring of abamectin resistance in P. xylostella and other arthropod pests.     

Seasonal changes of methamidophos susceptibility and biochemical properties in Plutella xylostella (Lepidoptera: Yponomeutidae) and its parasitoid Cotesia plutellae (Hymenoptera: Braconidae)

Methamidophos resistance and acetylcholinesterase (AChE) insensitivity to methamidophos, dichlorvos, and carbofuran were determined in the field populations of Plutella xylostella (L.) (Lepidoptera: Yponomeutidae) and its parasitoid Cotesia plutellae Kurdjumov (Hymenoptera: Braconidae) collected from the corresponding hosts between October 1998 and December 2003 in Fuzhou and Minhou, Fijian, China. Resistance levels to methamidophos and AChE insensitivity to the three insecticides in the two species of insects were high during autumn and spring and low during summer. Resistance to methamidophos was 15.3- and 12.6-fold higher in resistant F0 parents of P. xylostella and C. plutellae than in their susceptible F11 progeny, respectively. The bimolecular rate constant (k(i)) values of AChE to methamidophos, dichlorvos, and carbofuran were 4.6-, 6.3-, and 7.7-fold higher in F11 progeny of P. xylostella, and 3.7-, 4.5-, and 3.7-fold higher in F11 progeny of C. plutellae than those in their F0 parents, respectively. Compared with susceptible F11 progeny, the resistance ratios for methamidophos were 4.2-29.8 and 3.8-13.1 in 21 field populations of P. xylostella and C. plutellae, respectively. The k(i) values of AChE to methamidophos, dichlorvos, and carbofuran were 2.0-21.6-, 3.6-9.5-, and 2.6-9.2-fold higher in F11 progeny of P. xylostella, and 1.8-7.6-, 1.9-4.6-, and 2.2-7.6-fold higher in F11 progeny of C. plutellae than those in 21 field populations, respectively. Significant correlative variations of methamidophos resistance as well as significant correlative variations of k(i) values of AChE to insecticides between the two species of insects also were found in space and time. The k(i) values of AChE to insecticides in C. plutellae were far higher than those in P. xylostella. There were no obvious differences in the Km and Vmax of AChE between F0 parents and F11 progeny of P. xylostella and C. plutellae, respectively. But carboxylesterase activity was 1.6-fold higher in F0 parents of C. plutellae than in F11 progeny, and glutathione S-transferase activity was 1.5-fold higher in F0 parents of P. xylostella than in F11 progeny. The results suggested that the AChE insensitivity to insecticides might play the most important role in methamidophos resistance in the two species of insects. From these results, a spatial and temporal correlative evolution of methamidophos resistance and insensitive AChE was found to exist between P. xylostella and C. plutellae.     

小菜蛾有机磷抗性季节性变化及毒理机制研究

1998～ 2 0 0 3年期间的田间监测结果显示 ,福州地区小菜蛾 Plutella xylostella对甲胺磷和敌敌畏的抗性水平呈季节性变化 ,每年春秋季的抗性水平显著高于夏季 7月期间的抗性水平。与 2 5℃ 2 d的饲养条件相比 ,35℃ 2 d和 5℃ 30 d可使小菜蛾羧酸酯酶 (Car E)和谷胱甘肽 - S-转移酶 (GST)活力显著抑制 ,35℃ 2 d还可使小菜蛾乙酰胆碱酯酶 (ACh E)活力显著抑制 ,但 5℃4 d对小菜蛾 ACh E、Car E和 GST活力影响差异不显著。当反应温度均为 2 5℃时 ,在 35℃ 2 d、2 5℃ 2 d和 5℃ 30 d下饲养的小菜蛾 ACh E对甲胺磷和克百威的敏感性 (K i值 )没有明显变化 ,但酶与杀虫剂在 37℃的反应温度下 ,甲胺磷、敌敌畏和克百威对在 2 5℃下饲养的小菜蛾 ACh E的抑制作用显著增高。上述结果表明环境温度会影响小菜蛾的解毒代谢及杀虫剂对 ACh E的抑制作用。探讨了环境温度的季节性变化对田间小菜蛾有机磷抗性水平影响的毒理学机制。     

小菜蛾对几种常用药剂的敏感性测定

采用叶片浸溃法,在2001年10月和2002年10月分别测定了福州上街蔬菜基地的小菜蛾,对10种杀虫剂的敏感性。结果表明,上街菜区小菜蛾对灭多威、杀虫双、辛硫磷、毒死蜱、杀灭菊酯和功夫菊酯等农药极不敏感,已不能有效控制小菜蛾的危害。而小菜蛾对氟啶脲、阿维菌素、氟虫腈和虫螨腈比较敏感。通过两次毒力测定比较(2002年10月的LC50;2001年10月的LC50),结果表明,大多数杀虫剂敏感性变化较小。但小菜蛾对阿维菌素敏感性明显下降,毒力倍数达6．65倍,对氟虫腈毒力倍数相差1．48倍。此外,2002年10月小菜蛾对功夫菊酯的LC50为2001年10月的2．02倍。用浸叶法和浸溃法测定多杀菌素、氟虫腈与虫螨腈推荐浓度对小菜蛾幼虫的毒杀作用。结果表明3种药剂浸叶法处理效果均较理想。