Lack of fitness cost and inheritance of resistance to abamectin based on the establishment of a near-isogenic strain of Tetranychus urticae

Many populations of the two-spotted spider mite, Tetranychus urticae Koch, have developed high levels of resistance to the pesticide abamectin in China and other countries. This study developed a near-isogenic line to understand better the inheritance, cross-resistance, and fitness costs associated with abamectin resistance in the field population of T. urticae in China. We introduced the trait that confers extremely high abamectin resistance in a field-collected population of T. urticae into a susceptible laboratory strain(IPP-SS) to generate an abamectin-resistant near-isogenic line(NIL-Aba).This process was carried out through multiple backcrossing to IPP-SS and via parthenogenesis and abamectin screening. Compared with IPP-SS, the NIL-Aba strain had a 25 147-fold resistance to abamectin and a high level of cross-resistance to bifenthrin(288.17-fold), an intermediate level to emamectin benzoate(42.57-fold), and low levels to bifenazate, chlorfenapyr, cyflumetofen, cyenopyrafen, and cyetpyrafen with resistance ranging from 3.18-to 9.31-fold.But it had no cross-resistance to profenofos. The resistance to abamectin in NIL-Aba was autosomal, incompletely dominant, and polygenic. Based on two sex life table parameters, no fitness cost was found in NIL-Aba. Establishing the NIL-Aba strain provides a reliable basis for an in-depth study of abamectin resistance in T. urticae. New information on toxicological characteristics and fitness cost should facilitate the management of abamectin resistance in field populations of T. urticae.

ABAMECTIN与Bt制剂复配的杀虫增效作用

以菜青虫为试虫测定abamectin与Bt8010复配的毒力。结果表明abamectin—Bt8010的5种不同配比均有不同程度的增效作用,其中以5000IUBt8010+0.1％abamectin的增效作用最为显著,其共毒系数为289.4.室内药效测定结果,用该配比制成的可湿性粉剂对花椰菜、白菜、番茄、豌豆、蚕豆、茶树、柑桔、马尾松8种植物上分属鳞翅目、同翅目、鞘翅目、双翅目和蜱螨目的23种害虫有较好的杀灭效果。混配制剂对鳞翅目幼虫仅能提高用药24h后的杀灭率,并不能提高24h内的杀灭速度。

家蝇对Abamectin的抗性

<正> Abamectin是一组具有强大杀螨、杀虫、杀线虫活性的十六员大环内酯,是一种土壤放线菌Strepto-mycesavermitilis的天然发酵产物,即四种极相似的同系物:AbamectinA1,A2,B1和B2。其中Abamect-inB1（Abamectin,MK-936）是从液体发酵产物中分离

Efficacy Evaluation of 25% Abamectin·Etoxazole SC against Red Spider (Tetranychus cinnbarinus ) in Ornamental Rose

[Objective]The paper was to understand the control effect and the optimum dosage of 25% abamectin·etoxazole SC for controlling red spider in ornamental rose. [Method] Using stem-leaf spraying method,the control effect of 25% abamectin·etoxazole SC against red spider was determined. Significance of difference was examined by Duncan's new multiple range test( DMRT). [Result] The control effect of 25% abamectin · etoxazole SC sprayed at the dose of25-31. 25 mg a. i./kg on red spider was over 82. 0% at 21 d post spraying,higher than that of 110 g/L etoxazole SC sprayed at the dose of 27. 5 mg a. i./kg and1. 8% abamectin EC sprayed at the dose of 9 mg a. i./kg. [Conclusion]25% Abamectin·etoxazole SC sprayed at the doses of 25-31. 25 mg a. i./kg could effectively control the damage of red spider in ornamental rose,and can be widely used in production.

Effect Trials on Abamectin + Chlorpyrifos 8% GR for Controlling Turf Grubs

To screen high-efficiency, low-toxicity, and safe pesticides for controlling soil pests, experimental investigations of Abamectin ＋ Chlorpyrifos 8 % GR for controlling tuff grubs were implemented according to Field Pharrnacodynamic Test Standards of the Ministry of Agricuhure. The results showed that as the active in- gredient of Abamectin ＋ Chlorpyrifos 8% GR is 1 625 - 1 950 g/hm2, the control efficiency of tuff grubs is 81.43% -90.46% 3 - 10 days after pesticide applica- tion, the readily availability and persistent effect achieve the ideal level, and it is safe for turf.

Short-Time Derivatization Method for Analysis of Abamectin in Water Using High-Performance Liquid Chromatography Coupled to Fluorescence Detector

A method using a short-time derivatization step for the assessment of abamectin in water is presented. Abamectin derivative stable up to 7 days was obtained. Some regions where orange crops are present have received abamectin doses, aiming to increase the productivity and to combat pests and weeds, even when its residues reach the aquatic environment and interfere on water quality. Water samples from Jacaré-Pepira River (Brotas City, Brazil) nearby orange crops around urban zone, were evaluated for the presence of abamectin. The analytical method was validated resulting recovery around 108%, precision of 12%, accuracy of 104%, correlation coefficient of 0.9945, and detection and quantification limits of 0.1 μg·L﹣1 and 0.2 μg·L﹣1, respectively. Stable abamectin derivative was reached after 60 min of derivatization at room temperature (25&deg;C). No abamectin residues were found into samples.

In vitro Acute Cytotoxicity of Abamectin to the Gill Cell Line of Flounder Paralichthy olivaceus

The cytotoxicity of abamectin to the Gill Cell Line of Flounder (FG cell line) was examined in this study. It was found that the exposure of FG cells to abamectin caused the decreases of both cell growth rate and antioxidant enzyme activities,and the increase of intracellular O2- content. It was proposed that the reduction of antioxidant enzyme activities in FG cells caused the accu- mulation of O2- content in FG cells, leading to the change of cell morphology and even the death of cells. The results showed that FG cell line is suitable for the evaluation of the acute toxicity of abamectin.

亚致死浓度阿维菌素和毒死蜱对经历寄主转换的稻纵卷叶螟生长发育和繁殖的影响

【目的】本研究旨在明确寄主转换经历是否会改变亚致死浓度杀虫剂对稻纵卷叶螟Cnaphalocrocis medinalis生长发育和繁殖的影响,为杀虫剂的合理使用及稻纵卷叶螟的综合治理提供理论依据。【方法】从稻纵卷叶螟水稻种群和小麦种群中收集卵,并将其分别转换寄主植物饲养至2龄,作为具有不同寄主转换经历处理的幼虫[以水稻为食的水稻种群(R-R)、以小麦为食的水稻种群(R-W)、以小麦为食的小麦种群(W-W)和以水稻为食的小麦种群(W-R)]。利用离体叶片浸渍法对这些幼虫在亚致死浓度(LC_(25))阿维菌素和毒死蜱浸渍下的水稻或小麦叶片处理后48 h,测定3-5龄幼虫生长发育及成虫繁殖能力和寿命。【结果】未经杀虫剂处理时,寄主转换显著影响稻纵卷叶螟3-5龄幼虫总历期、化蛹率和蛹重,但对水稻种群和小麦种群的影响相反。LC_(25)浓度阿维菌素和毒死蜱处理2龄幼虫,显著延长3-5龄幼虫总历期,但延长程度因寄主转换经历而异。LC_(25)浓度阿维菌素显著降低各寄主转换经历幼虫的化蛹率(R-R组除外)。LC_(25)浓度毒死蜱仅显著降低W-W组的化蛹率。在2龄幼虫暴露于LC_(25)浓度阿维菌素后W-W和W-R组的蛹重显著降低。水稻种群化蛹率和蛹重受寄主转换的影响在LC_(25)浓度阿维菌素处理后消失,而小麦种群化蛹率和蛹重受寄主转换的影响在LC_(25)浓度阿维菌素和毒死蜱处理后均消失。无论是何种寄主转换经历还是LC_(25)浓度阿维菌素和毒死蜱处理均未影响成虫羽化率、交配率和单雌产卵量。寄主转换处理只显著影响未经杀虫剂处理时水稻种群的卵孵化率,但卵孵化率均未受LC_(25)浓度阿维菌素和毒死蜱处理影响。与未经杀虫剂处理相比,LC_(25)浓度阿维菌素和毒死蜱处理均未影响雌成虫寿命,但LC_(25)浓度毒死蜱处理显著增加了W-W组雄成虫寿命。【结论】寄主转换经历会影响阿维菌素和毒死蜱对稻纵卷叶螟的亚致死效应。LC_(25)浓度阿维菌素和毒死蜱处理经历寄主转换的稻纵卷叶螟幼虫后,其幼虫和蛹生长发育均受到不同程度影响,但成虫繁殖和寿命所受影响较小。使用针对稻纵卷叶螟的杀虫剂时和进行毒理实验时应考虑到寄主植物的潜在影响。

鲤在阿维菌素胁迫下肝胰腺组织的转录组分析

为了探究阿维菌素胁迫对鲤机体的响应机制,在水温(22±2.0)℃,将体质量(150±30)g的鲤(Cyprinus carpio)分别暴露在阿维菌素浓度0μg·L^(-1)(对照组)、1.5μg·L^(-1)和3.0μg·L^(-1)下5 d,采用转录组学测序分析方法,探究阿维菌素胁迫对鲤肝胰腺转录组学的影响,解析其对鲤的分子毒理机制。通过对所得基因的功能注释发现,被注释的差异基因主要与结合、催化和代谢等功能有关。KEGG通路富集分析结果显示,差异表达基因在药物代谢-细胞色素P450、药物代谢-其他酶、淀粉和蔗糖代谢等通路中显著富集,涉及药物代谢、氨基酸代谢、碳水化合物代谢、脂质代谢以及辅助因子和维生素的代谢等多个代谢过程。这些功能基因和预测通路为理解阿维菌素胁迫鲤体内解毒和免疫系统奠定了基础。本研究获得的转录组数据可为深入研究鱼类应对杀虫剂污染物的分子机制提供丰富的基因资源。

联苯肼酯与2种杀螨剂复配对柑橘全爪螨的联合毒力

柑橘全爪螨是一种世界性害螨,目前对许多药剂已经产生抗性。药剂复配是治理抗性问题,延长药剂使用寿命的重要手段。为筛选出增效明显的复配新产品,本文选取联苯肼酯作为标准药剂,与阿维菌素和氟啶胺分别进行复配,并采用叶碟喷雾法测定其联合毒力及增效作用。结果表明,联苯肼酯、阿维菌素和氟啶胺的单剂LC 50分别为16.43、0.29 mg/L和12.63 mg/L。联苯肼酯与阿维菌素复配比例为19∶1和15∶5的共毒系数分别为135.02和158.40,具有增效作用。联苯肼酯与氟啶胺在6∶4、7∶3、5∶5、9∶1、8∶2复配比例的共毒系数分别为466.28、410.61、370.22、311.15和275.85,增效作用显著。

Functional analysis of UG7207D3 associated with abamectin resistance in Tetranychus cinnabarinus(Boisduval)

Uridine diphosphate(UDP)-glycosyltransferases(UGTS)are widely distributed within living organisms and share roles in biotransformation of various lipophilic endo-and xenobiotics with activated UDP sugars.In this study,it was found that the activity of UGTs in abamectin-resistant(AbR)strain was significantly higher(2.3-fod)than that in susceptible strain(SS)of Tetramychus cinnabarinus.Further analysis showed that 5-nitrouracil,the inhibitor ofUGTs,could enhance the lethal effect of abamectin on mites.From the previous microarray results,we found an UGT gene(UGT201D3)overexpressed in AbR strain.Quantitative PCR analysis showed that UGT20ID3 was highly expressed and more inducible with abamectin exposure in the AbR strain.After silencing the tran-scription of UGT201D3,the activity of UGTs was decreased and the susceptibility to abamectin was increased in AbR strain whereas it was not in sS.Furthermore,UGT201D3 gene was then succefully expressed in Escherichia coli.The recombinant UGT20ID3 exhibited a-naphthol activity(2.810.43 nmol mg protein/min),and the enzyme activity could be inhibited by abamectin(inhibitory concentration at 50%:57.50±3.54 μmol/L).High-performance liquid chromatography analysis demonstrated that the recombinant UGT201D3 could efctively deplete abamectin(15.77%±3.72%)incubating with 150 ug protein for 6 h.These results provided direct evidence that UGT201D3 was involved in abamectin resistance in T cinnabarinus.

Low temperature purification method for the determination of abamectin and ivermectin in edible oils by liquid chromatographytandem mass spectrometry

In this study, a method based on low temperature purification （LTP） coupled with liquid chromatography-tandem mass spectrometry （LC-MS/MS） was developed for the determination of abamectin （ABA） and ivermectin （IVR） in edible oils. ABA and IVR were extracted using conventional liquid-liquid extraction followed by purification via precipitation of interfering fatty components at low temperature without an additional cleanup step. LTP is simple, easy to use, labour-saving and cost effective, and requires reduced amounts of organic solvent. The linear ranges of ABA and IVR were 5- 1000 t^g/L using matrix-matched standards. Limits of detection （LOD） and limits of quantification （LOQ） were in the range of 0.1-0.4 i^g/kg and 0.3-1.3 p^g/kg, respectively. The LOQs were below the strictest maximum residue limits established by Codex Alimentarius Commission. Recoveries at three spiked levels of 10, 20 and 100 i^g/kg in peanut oil, corn oil, olive oil, soybean oil and lard ranged from 71.1% to 119.3% with relative standard deviations of 3.2%-10.3%, which were in agreement with those obtained by the solid phase extraction method. The proposed method was utilized in the analysis of 10 edible oil samples from local market and neither ABA nor IVR was detected. As far as we know, this is the first time that LTP is applied to the determination of avermectins in edible oils.

Acute toxicity test of pesticide abamectin on common carp(Cyprinus carpio)

Objective:To determine acute toxicity of abamectin(abamectin used for agricultural fields and also is a common acaridae used in farms)to common carp(Cyprinus carpio).Methods:In this research,common carps were exposed to abamectin for 96 h.LC_(50) values of 24 h,48 h,72 h and 96 h were attained by probit analysis software SPSS Version 16.Fish were exposed to different concentrations(1,2,3,6,12 and 15 mg/L)of abamectin for 96 h and physicochemical properties of water used for these experiments were stable and every mortality was recorded daily.Results:The 96 h LC_(50)of abamectin for Cyprinus carpio was 1.243 mg/L.Conclusions:Eventually toxicity values indicated that abamectin has same toxicity in studied other specie and we can state lower value of LC_(50)for studied specie in compare with most species.

高效液相色谱法测定25%四唑虫酰胺·阿维菌素悬浮剂

建立了高效液相色谱法测定25%四唑虫酰胺·阿维菌素悬浮剂的含量,以甲醇+乙腈+0.8%冰乙酸水溶液为流动相、C18色谱柱、柱温35℃、进样体积为5μL、DAD检测器,在波长244 nm条件下,对四唑虫酰胺和阿维菌素进行定量分析。结果表明,四唑虫酰胺和阿维菌素的线性关系良好,线性相关系数R^(2)分别为0.9999、0.9998,相对标准偏差为0.026、0.030。在样品中的平均添加回收率为99.7%、99.9%。该方法操作简单,精密度和准确度高,适用于制剂中含有阿维菌素和四唑虫酰胺的定量分析。

Influences of insecticides on toxicity and cuticular penetration of abamectin in Helicoverpa armigera

Synergistic actions for mixtures of abamectin with other insecticides in some insect pests were evaluated, and the possible synergistic mechanism was studied by the comparison in toxicity and cuticular penetration of abamectin between with and without other insecticides or synergists in Helicoverpa armigera larvae. The results of bioassay showed that horticultural mineral oil (HMO), hexaflumuron, chlorpyrifos, and some other insecticides were synergistic to abamectin with 152.0-420.0 of co-toxicity coefficient(CTC) in some agricultural insect pests. In topical application tests, HMO or piperonyl butoxide (PBO) increased the toxicity of abamectin in larvae of H. armigera, but the mortality was not affected by s,s,s-tributylphorotrithioate (DEF) and triphenylphosphate (TPP). The synergistic action of HMO was obviously higher than PBO, and when treated simultaneously with abamectin, HMO gave a more significant synergism than if treated 2 hours ahead. The highest synergistic effect (SE) was found in the mixture of ‘abamectin+HMO (1:206)'. The mortality did not increase or the toxicity drop, when a synergist or HMO was added into the mixture of ‘abamectin+HMO' or ‘abamectin+synergist', respectively. Results from the isotope tracing experiments showed that HMO significantly enhanced the penetration of ^3H-abamectin through the cuticle of H.armigera larvae, which resulted in the synergism of the mixture. The cuticular penetration of ^3H-abamectin was not accumulatively affected by chlorpyrifos, nor by hexaflumuron,though there was an inhibition within 30 seconds or 1 hour after treated by these two chemicals respectively. Results suggested that the synergism of abamectin mixed with hexaflumuron or chlorpyrifos might be related to inhibition of metabolic enzymes or target sites in the larvae.

Abamectin resistance in strains of vegetable leafminer, Liriomyza sativae （Diptera： Agromyzidae） is linked to elevated glutathione S-transferase activity

Abamectin resistance was selected in the vegetable leafminer, Liriomyza sativae （Blanchard） （Diptera： Agromyzidae） under laboratory conditions, and cross- resistance patterns and possible resistance mechanisms in the abamectin-resistant strains （AL-R, AF-R） were investigated. Compared with the susceptible strain （SS）, strain AL-R displayed 39-fold resistance to abamectin after 20 selection cycles during 25 generations, and strain AF-R exhibited 59-fold resistance to abamectin after 16 selection cycles during 22 generations. No cross-resistance to cyromazine was found in both abamectin-resistant strains. However, we failed to select for cyromazine resistance in L. sativae under laboratory conditions by conducting 17 selection cycles during 22 generations. However, moderate levels of cross-resistance to abamectin （6-9 fold） were observed in strains which received cyromazine treatments. Biochemical analysis showed that glutathione S-transferase （GST） activity in both abamectin-resistant strains （AL-R, AF-R） was significantly higher than in the susceptible strain （SS）, suggesting metabolically driven resistance to abamectinin L. sativae. Recommendations of mixtures or rotation of cyromazine and abamectin should be considered carefully, as consecutive cyromazine treatments may select for low-level cross-resistance to abamectin.

Effects of abamectin selection on the genetic differentiation within Plutella xylostella （Lepidoptera： Plutellidae） based on amplified fragment length polymorphism

Diamondback moth, Plutella xylostella （L.） is one of the most serious insect pests for its remarkable ability to develop resistance to virtually every insecticide that has been used against it. In the present study, amplified fragment length poly- morphism （AFLP） is used to study the genetic differentiation as well as the effects of abamectin-selection on population genetic differentiation for P. xylostella. A dendrogram was constructed from the matrix of genetic distances using the STATISTICA software （Version 4.5） and unweighted pair-group method with arithmetic averages （UPGMA）. The data demonstrated that compared to the susceptible strain （ABM-s）, the heterozy- gosity in the abamectin-resistant strain （ABM-r） decreased with the increased selection pressure and resistant level. When the resistance ratio was below 4.3, there was no sig- nificant differentiation at the genome DNA level. When the resistance ratio reached 5.8, a fairly significant differentiation began to appear, and when the resistance ratio reached and exceeded 8.1, there appeared a significant genetic differentiation. The results suggest that abamectin selection is associated with increased genetic polymorphism in P. xylostella.

阿维菌素对瓜实蝇3种解毒酶系的影响

【目的】探讨阿维菌素对瓜实蝇[Bactrocera cucurbitae(Coquillett)]解毒酶系的影响,明确瓜实蝇阿维菌素抗性与解毒酶的关系,为瓜实蝇抗药性综合治理和科学用药提供理论基础。【方法】采用饲毒法测定阿维菌素对瓜实蝇成虫敏感品系(SS)和抗阿维菌素品系(RS)的亚致死浓度(LC_(25))及致死中浓度(LC_(50));利用微孔板法测定SS品系和RS品系经阿维菌素LC_(25)、LC_(50)剂量处理12、24、48和72 h后其体内谷胱甘肽S-转移酶(Glutathione S-transferase,GSTs)、羧酸酯酶(Carboxylesterase,CarE)活性,采用ELISA试剂盒法测定细胞色素P450单加氧化酶(Cytochrome P450 monooxygenases,P450s)含量;测定比较SS品系和RS品系GSTs、CarE米氏常数(K_(m))及最大反应速率(V_(max))的变化及增效剂顺丁烯二酸二乙酯(DEM)、磷酸三苯酯(TPP)和增效醚(PBO)对阿维菌素的增效作用。【结果】与SS品系相比,RS品系体内GSTs和CarE活性均显著上升(P<0.05,下同),分别为SS品系的2.92和1.46倍,P450s含量则显著下降,为SS品系的68.0%。SS品系在LC_(25)剂量的阿维菌素处理后12、48 h及LC_(50)处理后12、24、48 h和RS品系在LC_(25)剂量处理后12 h、LC_(50)处理后72 h,其体内GSTs活性均被诱导显著增强;LC_(25)剂量处理后24 h,SS品系体内CarE活性被诱导显著增强,RS品系中LC_(25)处理后72 h和LC_(50)处理后各时间段CarE活性表现为被显著抑制;LC_(50)处理后12 h,P450s含量在SS品系中表现为显著降低,而在72 h则显著升高。与SS品系相比,RS品系GSTs的K_(m)显著降低,V_(max)显著升高,CarE的K_(m)和V_(max)变化不明显;增效剂DEM、TPP和PBO在SS品系中的增效比分别为1.03、1.04和2.08,在RS品系中的增效比分别为3.45、2.52和2.26,相对增效系数分别为0.71、0.60和0.54。【结论】GSTs和CarE解毒酶参与了瓜实蝇对阿维菌素的抗性形成,其中GSTs活性发生了量变和质变,其对底物亲和力增加和代谢速度增快,在瓜实蝇对阿维菌素抗性形成中起到主导作用。

松材线虫谷胱甘肽S转移酶基因响应阿维菌素胁迫功能研究

【目的】由松材线虫Bursaphelenchusxylophilus引起的松材线虫病严重破坏东亚和欧洲等多个国家和地区的森林生态系统。【方法】本研究从松材线虫基因组中获取Bx-gst12,随后对该基因的全长CDS区域进行基因克隆和序列分析、同时通过生物信息学方法对Bx-gst12所编码的蛋白质Bx-GST12的理化性质、亲疏水性、跨膜区、二级结构和三级结构进行了预测和分析。并通过基因干扰技术对Bx-gst12干扰后,分析该基因在松材线虫对阿维菌素敏感程度的影响。【结果】生物信息学结果显示Bx-GST12蛋白稳定系数为28.96,亲水系数为-0.412,三级结构预测Bx-GST12蛋白具有含有9个α螺旋和5个β折叠,但不具有跨膜结构域。应用基因干扰技术对Bx-gst12基因进行基因干扰,干扰后的Bx-gst12基因表达量变为原来的25.14%。阿维菌素溶液生物测定实验结果表明,Bx-gst12干扰后的松材线虫死亡率明显高于对照组,松材线虫死亡率平均提高了7.12%。【结论】本研究成功克隆Bx-gst12基因并对该基因的dsRNA进行了设计与合成。Bx-gst12基因干扰显著影响了松材线虫对阿维菌素的敏感性,在相同浓度的阿维菌素胁迫相同时间中,干扰组线虫死亡率明显高于对照组,表明Bx-gst12基因在松材线虫药物代谢过程中发挥着显著作用。

山药中噻唑膦和阿维菌素的残留检测及膳食风险评估

为评价噻唑膦和阿维菌素在山药上使用的安全性,采用超高效液相色谱-质谱联用仪检测,分析山药中噻唑膦和阿维菌素残留量,并运用膳食摄入风险评估模型进行长期膳食摄入风险评估。结果表明,在0.01~1 mg/kg添加水平下,噻唑膦和阿维菌素在山药上的平均回收率分别为87%~110%和80%~89%,相对标准偏差分别为0.6%~5.5%和1.0%~2.6%,山药中噻唑膦和阿维菌素最终残留量均小于0.01 mg/kg。噻唑膦施药有效剂量为3000 g/hm^(2);阿维菌素施药有效剂量为375 g/hm^(2),于播种前施药1次并在收获期采收山药,噻唑膦和阿维菌素的普通人群国家估计每日摄入量分别是0.047、0.059 mg,风险商分别为18.7%、93.4%,说明其对一般消费人群是安全的。