七种烟碱类杀虫剂对甘蓝蚜虫的室内毒力比较

明确吡虫啉、啶虫脒等7种烟碱类杀虫剂对甘蓝蚜虫的毒力。采用浸渍法对7种烟碱类杀虫剂对甘蓝蚜虫的室内毒力测定。甘蓝蚜虫对啶虫脒的敏感性最高,LC_(50)为1.7566 mg/L,甘蓝蚜虫对吡虫啉的敏感性最低,其LC_(50)为12.2627 mg/L,七种烟碱类杀虫剂对甘蓝蚜虫的活性由高到低的顺序依次为啶虫脒噻虫嗪噻虫啉噻虫胺呋虫胺烯啶虫胺吡虫啉。啶虫脒、噻虫嗪对甘蓝蚜虫的活性较高,可以进行推广应用,但要密切注意这类药剂交互抗性的发展。     

9种杀虫剂对马铃薯桃蚜的室内毒力测定

为了筛选防治马铃薯上桃蚜的更好药剂,在室内采用叶片浸渍法,测定了9种杀虫剂对马铃薯桃蚜的毒力。结果表明:9种杀虫剂对马铃薯桃蚜都有较好的毒力,其中3.15%阿维·吡虫啉EC对马铃薯桃蚜的毒力最高,LC50值为0.730 4 mg/L;其次是5%高效氯氟氰菊酯ME、33%氯氟·吡虫啉SC、3.2%阿维菌素EC和9%噻虫·高氯氟SC,LC50值分别为0.873 1 mg/L、1.384 9 mg/L、1.855 3 mg/L和2.660 7 mg/L;22%氟啶虫胺腈SC、30%噻虫嗪SC和20%噻虫胺SC的LC50值分别为5.782 8 mg/L、5.8653 mg/L和6.279 3 mg/L;20%吡虫啉SL对马铃薯桃蚜的毒力最低,LC50值为22.895 2 mg/L。     

8个烟碱类杀虫剂生物活性比较研究

比较吡虫啉、啶虫脒、烯啶虫胺、噻虫啉、噻虫嗪、噻虫胺、氯噻啉、呋虫胺等8个烟碱类杀虫剂的生物活性,为科学应用提供参考。采用浸渍法、浸稻苗法、浸叶碟法等对豆蚜、褐飞虱、二化螟、小菜蛾进行室内毒力测定,对活性进行分组,并进行了结构与活性关系初步分析。结果表明:烟碱类药剂对豆蚜LC50值为0.0314⁰.3505 mg/L,对抗吡虫啉的褐飞虱LC50值为0.565 70.3505 mg/L,对抗吡虫啉的褐飞虱LC50值为0.565 7⁴9.404 6 mg/L,对二化螟LC50值为7.517649.404 6 mg/L,对二化螟LC50值为7.5176¹39.0369 mg/L,对小菜蛾LC50值为10.533 4139.0369 mg/L,对小菜蛾LC50值为10.533 4¹00 mg/L。烟碱基闭环与开环、取代杂环等结构特点对药剂活性有影响。烟碱类药剂对同翅目害虫的活性显著优于对鳞翅目害虫的活性。在实际应用中可以采取轮用策略和兼治策略推进药剂的科学合理使用,还可加强研发种子处理剂等。     

柑橘木虱对4种新烟碱类杀虫剂的交互抗性

[目的]探明柑橘木虱在新烟碱类杀虫剂之间是否存在交互抗药性,为开发和应用这类杀虫剂提供依据。[方法]用药膜法测定了不同来源的柑橘木虱成虫对吡虫啉、噻虫嗪、呋虫胺的LC50、LC95和抗性指数。[结果]已对吡虫啉、啶虫脒产生抗药性的柑橘木虱种群,虽然从未施用过噻虫嗪、呋虫胺和其他新烟碱类杀虫剂,但对它们的抗性倍数也已达低抗至中等抗性水平。[结论]柑橘木虱在新烟碱类杀虫剂噻虫嗪、呋虫胺、吡虫啉、啶虫脒之间可能存在交互抗性。     

17种杀虫剂对细胸金针虫的毒力评价

采用土壤混药法,测定了17种杀虫剂对细胸金针虫的室内毒力.结果表明:供试药剂中苯并吡唑类杀虫剂氟虫腈对细胸金针虫幼虫的毒力最高,LC50值为0.007613 mg/kg土.有机磷类杀虫剂也具有较高的毒力,其中二嗪磷、毒死蜱和辛硫磷的毒力最高,3种杀虫剂的LC50值分别为0.0612、0.1007、0.1230 mg/kg土;哒嗪硫磷和丙溴磷的毒力也较高,其LC50值均低于5 mg/kg土;马拉硫磷和敌百虫对试虫的毒力较低,LC50值分别为6.4887、13.801 8 mg/kg土.氯代烟酰类杀虫剂对试虫也具有较高的毒力,其中氯噻啉对试虫的LC50值为2.638 5 mg/kg土,啶虫脒LC50值为3.2364 mg/kg土,吡虫啉的毒力较低,其LC50值10.8264 mg/kg土.拟除虫菊酯类杀虫剂氯氰菊酯和氰戊菊酯对试虫也具有一定的毒力,其LC50值分别为11.1860、22.289 1 mg/kg土.微生物源杀虫剂阿维菌素和几丁质合成抑剂灭幼脲、杀铃脲和除虫脲对细胸金针虫幼虫的毒力较低,在剂量为 50 mg/kg土时,其校正死亡率均在40%以下.     

7种新烟碱类杀虫剂对意大利蜜蜂的急性毒性及风险评价

[目的]评价生产中常用的新烟碱类杀虫剂对蜜蜂的急性毒性及风险性。[方法]参照《化学农药环境安全评价试验准则》,测定7种生产中常用的新烟碱类杀虫剂对蜜蜂的急性接触毒性和经口毒性,并利用EPP0采取的计算危害商(HQ)值的方法对7种新烟碱类杀虫剂做风险性评价。[结果]噻虫嗪、噻虫胺、呋虫胺、吡虫啉对蜜蜂在急性毒性为高毒甚至剧毒,风险性为中等风险到高风险;烯啶虫胺急性毒性虽较高,但风险性相对较低;啶虫脒和噻虫啉急性毒性为中毒或低毒,风险性均为低风险。[结论]生产中选择对蜜蜂风险性低的品种(啶虫脒、噻虫啉、烯啶虫胺),避开蜜源区和需要蜜蜂授粉的植物。     

新烟碱类杀虫剂 竞争中成为市场热点

<正>新烟碱类化合物是一类高效、安全、高选择性的新型杀虫剂,在国内外市场发展很快。国内从上世纪80年代末就开始了对新烟碱类杀虫剂的研究开发,目前已取得不少进展。新烟碱类杀虫剂有:吡虫啉、啶虫脒、烯啶虫胺、氯噻啉、噻虫啉、噻虫嗪、噻虫胺、呋虫胺等。据预测,新烟碱类产品今后5年内将占全球农药总量的15%～20%。     

6种新烟碱类杀虫剂对德国小蠊药效试验

[目的]评价呋虫胺、噻虫啉、烯啶虫胺、啶虫咪、噻虫嗪和吡虫啉6种新烟碱类杀虫剂对德国小蠊的杀虫活性。[方法]采用药膜法和饲喂法分别测定杀虫剂对德国小蠊的触杀和胃毒活性。[结果]除噻虫啉外,其余5种新烟碱类杀虫剂对德国小蠊成虫和3龄若虫的触杀活性均高于氟虫腈。呋虫胺活性最高,KT50分别为6.29、5.90 min。1%饵剂饲喂成虫和3龄若虫72 h的死亡率均可达到75%以上。其中呋虫胺为最高,分别为98.15%和94.27%,稍逊氟虫腈(100%、100%)。[结论]呋虫胺对德国小蠊具有极好的触杀和胃毒活性,是一个替代氟虫腈合适的候选卫生杀虫剂。     

新烟碱类与拟除虫菊酯类杀虫剂对蚜虫的联合作用研究

研究比较了噻虫嗪、噻虫啉、烯啶虫胺、氯噻啉等4个新烟碱类杀虫剂与高效氯氟氰菊酯、联苯菊酯等2个拟除虫菊酯类杀虫剂的联合作用,为复配制剂的研发提供科学依据。室内采用浸渍法对蚕豆蚜进行毒力测定,采用等效线法和共毒系数法评价联合作用类型。结果表明:8个新烟碱类杀虫剂对蚜虫的活性从高到低依次为噻虫嗪、吡虫啉、噻虫啉、烯啶虫胺、啶虫脒、噻虫胺、氯噻啉、呋虫胺,4个拟除虫菊酯类杀虫剂对蚜虫的活性从高到低依次为高效氯氟氰菊酯、溴氰菊酯、高效氯氰菊酯、联苯菊酯。18个组合的联合作用表现出增效、相加或拮抗等,并未发现明显规律。从18个组合中优先推荐烯啶虫胺+高效氯氟氰菊酯(5∶1)、噻虫嗪+联苯菊酯(5∶1)。在复配研发时,切不可盲目模仿,必须以实际筛选试验结果为依据,也希望复配具有科学性和实用性,并在抗性治理和减量使用中发挥应有的作用。     

荷兰全面禁止新烟碱农药的使用

正新烟碱类杀虫剂为当今全球最大的一类植物源杀虫剂,其作用机制主要是通过选择性控制昆虫神经系统烟碱型乙酰胆碱酯酶受体,阻断昆虫中暑神经系统的正常传导,从而导致害虫出现麻痹进而死亡。目前已商品化或即将商品化的新烟碱类杀虫剂有:吡虫啉、啶虫脒、噻虫嗪、噻虫啉、呋虫胺、烯啶虫胺、噻虫胺、氟啶虫酰胺、nithiazine、AKD-1022、JP-339、cyanotropanes(Ⅰ、Ⅱ)等。但     

新烟碱类杀虫剂与种子处理

对商品化的新烟碱类杀虫剂吡虫啉、噻虫嗪、噻虫胺及啶虫眯在种子处理方面国内外目前登记的产品、登记作物、防治对象、防治效果等方面做了综述.分析了我国目前发展中存在的问题,新烟碱类杀虫剂开发用于种子处理剂的产品较少,国内缺乏品质优良的成膜剂助剂,一些害虫对烟碱类杀虫剂产生抗性等,并对今后在种子处理中的应用提出了一些见解和展望.     

Mode of Action of Neonicotinoid Insecticides Imidacloprid and Thiacloprid to the Cockroach Pameα7 Nicotinic Acetylcholine Receptor

The functional expression of the cockroach Pameα7 nicotinic acetylcholine receptor subunit has been previously studied, and was found to be able to form a homomeric receptor when expressed in Xenopus laevis oocytes. In this study, we found that the neonicotinoid insecticide imidacloprid is unable to activate the cockroach Pameα7 receptor, although thiacloprid induces low inward currents, suggesting that it is a partial agonist. In addition, the co-application or 5 min pretreatment with 10 µM imidacloprid increased nicotine current amplitudes, while the co-application or 5 min pretreatment with 10 µM thiacloprid decreased nicotine-evoked current amplitudes by 54% and 28%, respectively. This suggesting that these two representatives of neonicotinoid insecticides bind differently to the cockroach Pameα7 receptor. Interestingly, the docking models demonstrate that the orientation and interactions of the two insecticides in the cockroach Pameα7 nAChR binding pocket are very similar. Electrophysiological results have provided evidence to suggest that imidacloprid and thiacloprid could act as modulators of the cockroach Pameα7 receptors.     

杀虫剂吡虫啉的合成进展

吡虫啉是一种高效、低毒、低污染、高选择性的烟碱类杀虫剂。在介绍吡虫啉性质的基础上,着重讨论了吡虫啉重要中间体2-氯-5-氯甲基吡啶的制备和吡虫啉的合成路线,同时展望了吡虫啉的市场前景。     

High Performance of Ionic-Liquid-Based Materials to Remove Insecticides

Neonicotinoids are systemic insecticides commonly used for pest control in agriculture and veterinary applications. Due to their widespread use, neonicotinoid insecticides (neonics) are found in different environmental compartments, including water, soils, and biota, in which their high toxicity towards non-target organisms is a matter of great concern. Given their widespread use and high toxicity, the development of strategies to remove neonics, while avoiding further environmental contamination is of high priority. In this work, ionic-liquid-based materials, comprising silica modified with tetraalkylammonium cations and the chloride anion, were explored as alternative adsorbent materials to remove four neonics insecticides, namely imidacloprid, acetamiprid, thiacloprid, and thiamethoxam, from aqueous media. These materials or supported ionic liquids (SILs) were first synthesized and chemically characterized and further applied in adsorption studies. It was found that the equilibrium concentration of the adsorbate in the solid phase decreases with the decrease in the SIL cation alkyl chain length, reinforcing the relevance of hydrophobic interactions between ionic liquids (ILs) and insecticides. The best-identified SIL for the adsorption of the studied insecticides corresponds to silica modified with propyltrioctylammonium chloride ([Si][N₃₈₈₈]Cl). The saturation of SILs was reached in 5 min or less, showing their fast adsorption rate towards all insecticides, in contrast with activated carbon (benchmark) that requires 40 to 60 min. The best fitting of the experimental kinetic data was achieved with the Pseudo Second-Order model, meaning that the adsorption process is controlled at the solid-liquid interface. On the other hand, the best fitting of the experimental isotherm data is given by the Freundlich isotherm model, revealing that multiple layers of insecticides onto the SIL surface may occur. The continuous removal efficiency of the best SIL ([Si][N₃₈₈₈]Cl) by solid-phase extraction was finally appraised, with the maximum adsorption capacity decreasing in the following sequence: imidacloprid > thiacloprid > thiamethoxam > acetamiprid. Based on real reported values, under ideal conditions, 1 g of [Si][N₃₈₈₈]Cl is able to treat at least 10⁶ m³ of wastewater and water from wetland contaminated with the studied neonics. In summary, the enhanced adsorption capacity of SILs for a broad diversity of neonics was demonstrated, reinforcing the usefulness of these materials for their removal from aqueous matrices and thus contributing to preventing their introduction into the ecosystems and reducing their detrimental effects in the environment and human health.     

噻虫啉对蚜虫杀虫活性及田间药效评价

采用农药生物测定标准操作程序(SOP)比较测定了噻虫啉和吡虫啉对蚜虫的毒力。室内生物测定结果表明,噻虫啉和吡虫啉对蚜虫有良好的杀虫活性,其毒力平均LC50分别为1.24mg/L和1.45mg/L。田间小区试验结果表明,噻虫啉对蚜虫表现出良好的防治效果,有效用量为3.36、6.72、10.08g/667m2时,药后1～10d的防治效果分别为85.82%～89.55%、89.25%～92.08%、92.43%～96.34%,好于剂量相当的吡虫啉的防治效果。     

Degradation of neonicotinoid insecticides by different advanced oxidation processes and studying the effect of ozone on TiO2 photocatalysis

Although some studies concerning the effect of pH and ozone dosage on TiO₂ photocatalysis (O₂/TiO₂/UV) have already been published, no complete investigation and explanation of the effects of both parameters on photocatalytic ozonation (O₃/TiO₂/UV) have been carried out. Aqueous solutions of neonicotinoid insecticides (thiacloprid and imidacloprid) were chosen as a degradation medium, since they exhibit a high threat for aquatic systems and it is of great importance to find an effective method for their elimination from the environment. In preliminary stability tests, thiacloprid showed higher photo- and chemical stability compared to imidacloprid, therefore its degradation was studied in detail. To assess the suitability of various treatments for degradation and mineralization of thiacloprid in water at different pH values and ozone dosages, we applied ozonation (O₃) and three different photochemical advanced oxidation processes, namely ozonation, coupled with UV radiation (O₃/UV), O₃/TiO₂/UV and O₂/TiO₂/UV. Light source emitting mainly in UVA range was applied in all three processes. The photocatalytic ozonation (O₃/TiO₂/UV) was found to be the most efficient process irrespective of pH. The synergistic effect of ozone and TiO₂ photocatalysis was noticed at acidic and neutral pH, but the synergism was lost at basic pH, probably due to faster self-decompositon of ozone under alkaline conditions. At acidic pH, also the oxidation of chloride anions to chlorate(V) was noticed in O₃/TiO₂/UV and in O₃/UV processes. By plotting the disappearance rate constants of thiacloprid degradation in O₃/TiO₂/UV and O₃/UV systems as a function of the flow rate of ozone, the synergistic effect of ozone was undoubtedly proven. The slope of the linear fit in case of O₃/TiO₂/UV process was considerably steeper than in case of O₃/UV, which would not happen in absence of synergistic effect. The linearity in O₃/TiO₂/UV system was lost only at very high flow rates of ozone.     

3种杀虫剂不同剂型对葡萄蓟马的室内生物活性及田间防效

[目的]为明确避雨栽培葡萄上3种常用杀虫剂及不同剂型对葡萄蓟马的室内生物活性和葡萄不同生长期的田间防治效果。[方法]试验采用浸液饲喂法测定了葡萄蓟马的室内种群活性,并进行田间防效试验。[结果]3种杀虫剂对葡萄蓟马的室内生物活性啶虫脒和阿维菌素较高,吡虫啉相对较低,依次为啶虫脒EC>啶虫脒WG>阿维菌素EC>吡虫啉EC>吡虫啉WG;田间防效试验发现,在葡萄的花前期和浆果生长期啶虫脒施药后1 d的防效均在60%以上,施药后7 d啶虫脒和阿维菌素的防效均在80%~95%,而吡虫啉的防效在不同时期施用均低于80%;不同剂型间,乳油表现出相对较好的防治效果。[结论]阿维菌素和啶虫脒可推荐为避雨栽培葡萄上防治蓟马的首选药剂,2者属于不同类型杀虫剂,适宜交替使用,能降低蓟马对杀虫剂快速产生抗性的风险,应该在葡萄花期前对蓟马进行防除,防止其数量暴发。     

5种杀虫剂对不同发育阶段螟黄赤眼蜂的安全性评价

[目的]明确5种常用杀虫剂对不同发育阶段螟黄赤眼蜂的安全性。[方法]在实验室条件下采用药膜法测定了5种药剂对螟黄赤眼蜂成蜂的毒性及对不同发育阶段赤眼蜂羽化率的影响。[结果]高效氯氰菊酯对螟黄赤眼蜂成蜂的毒性最强,LR₅₀是9.16×10^-6mg/cm²,为极高风险性杀虫剂;阿维菌素、吡虫啉、呋虫胺对螟黄赤眼蜂成蜂的毒性较强,LR₅₀分别是5.49×10^-5、8.24×10^-5、1.28×10^-4mg/cm²,为高风险性杀虫剂;氯虫苯甲酰胺对螟黄赤眼蜂成蜂的毒性最弱,LR₅₀是1.54×10^-2,为低风险性杀虫剂。阿维菌素在螟黄赤眼蜂整个发育阶段尤其在卵期和幼虫期处理,呋虫胺、吡虫啉、高效氯氰菊酯和氯虫苯甲酰胺在螟黄赤眼蜂预蛹期和蛹期处理,螟黄赤眼蜂的羽化率显著降低。[结论]氯虫苯甲酰胺对螟黄赤眼蜂各发育阶段均较安全,值得推广使用。在大田释放赤眼蜂进行生物防治时,应避免高风险性杀虫剂的使用,以避免对赤眼蜂造成伤害。