三七,白芍及西洋参中氯氰菊酯,氰戊菊酯和溴氰菊酯的残留量测定

测定西洋参,三七和白芍中氯氰菊酯,氰戊菊酯和溴氰菊酯３种农药的残留量,方法：运用石油醚－丙酮混合溶剂提取及毛细管气相色谱法测定。结果氯氰菊酯,氰戊菊酯和溴氰菊酯的添加回收率分别为９２．１３－１００．５,９７．５４－１０６．４,９４．８９－１０８．５;ＲＳＤ（％）分别为１．２９－５．６４,０．７０－４．８７,１．７１－５．３４。被测样品中,三七中含有氰戊菊酯和溴氰菊酯的添加回收率,个别样品含溴氰菊酯     

Overcoming super‐knock down resistance (super‐kdr) mediated resistance: multi‐halogenated benzyl pyrethroids are more toxic to super‐kdr than kdr house flies

Target site insensitivity because of mutations in the voltage‐sensitive sodium channel gene (Vssc) is a major mechanism of resistance to pyrethroid insecticides in the house fly, Musca domestica. There are three known Vssc alleles that confer resistance to pyrethroids in the house fly: knock down resistance (kdr; L1014F), super‐kdr (M918T + L1014F) and kdr‐his (L1014H), but there has been no side‐by‐side comparison of the resistance levels that they confer. We compared the levels of resistance conferred by the three Vssc alleles in congenic strains to 19 structurally diverse pyrethroids, and compared the full‐length Vssc cDNA sequences from each strain. Generally, the levels of resistance conferred were kdr‐his < kdr < super‐kdr. However, there was significant variation in this pattern, especially for super‐kdr, for which both high and low resistance ratios were observed for several pyrethroids. We also examined the levels of resistance in heterozygotes. Resistance in each of the hybrids was generally inherited as an incompletely recessive trait, except for the kdr‐his/kdr hybrids, which showed incompletely to completely dominant resistance (ie had resistance levels comparable to kdr homozygotes). The importance of these results to understanding the frequencies of these resistance alleles in natural populations, the evolution of insecticide resistance and resistance management strategies are discussed.     

A survey of pyrethroid‐resistant populations of Meligethes aeneus F. in Poland indicates the incidence of numerous substitutions in the pyrethroid target site of voltage‐sensitive sodium channels in individual beetles

The pollen beetle (Meligethes aeneus F.) is the most devastating pest of oilseed rape (Brassica napus) and is controlled by pyrethroid insecticides. However, resistance to pyrethroids in Europe is becoming widespread and predominant. Pyrethroids target the voltage‐sensitive sodium channel (VSSC), and mutations in VSSC may be responsible for pyrethroid insensitivity. Here, we analysed individual beetles that were resistant to esfenvalerate, a pyrethroid, from 14 populations that were collected from oilseed rape fields in Poland. We screened the VSSC domains that were presumed to directly interact with pyrethroids. We identified 18 heterozygous nucleic acid substitutions, amongst which six caused an amino acid change: N912S, G926S, I936V, R957G, F1538L and E1553G. Our analysis of the three‐dimensional structure of these domains in VSSC revealed that some of these changes may slightly influence the protein structure and hence the docking efficiency of esfenvalerate. Therefore, these mutations may impact the susceptibility of the sodium channel to the action of this insecticide.     

Comparative toxicity of pyrethroid insecticides to two estuarine crustacean species,Americamysis bahia and Palaemonetes pugio

Pyrethroid insecticides are widely used on agricultural crops, as well as for nurseries, golf courses, urban structural and landscaping sites, residential home and garden pest control, and mosquito abatement. Evaluation of sensitive marine and estuarine species is essential for the development of toxicity testing and risk‐assessment protocols. Two estuarine crustacean species, Americamysis bahia (mysids) and Palaemonetes pugio (grass shrimp), were tested with the commonly used pyrethroid compounds, lambda‐cyhalothrin, permethrin, cypermethrin, deltamethrin, and phenothrin. Sensitivities of adult and larval grass shrimp and 7‐day‐old mysids were compared using standard 96‐h LC₅₀ bioassay protocols. Adult and larval grass shrimp were more sensitive than the mysids to all the pyrethroids tested. Larval grass shrimp were approximately 18‐fold more sensitive to lambda‐cyhalothrin than the mysids. Larval grass shrimp were similar in sensitivity to adult grass shrimp for cypermethrin, deltamethrin, and phenothrin, but larvae were approximately twice as sensitive to lambda‐cyhalothrin and permethrin as adult shrimp. Acute toxicity to estuarine crustaceans occurred at low nanogram per liter concentrations of some pyrethroids, illustrating the need for careful regulation of the use of pyrethroid compounds in the coastal zone. © 2013 Wiley Periodicals, Inc. Environ Toxicol 29: 1099–1106, 2014.     

Diversity of knockdown resistance alleles in a single house fly population facilitates adaptation to pyrethroid insecticides

Insecticide use exerts a tremendous selection force on house fly populations, but the frequencies of the initial resistance mutations may not reach high levels if they have a significant fitness cost in the absence of insecticides. However, with the continued use of the same (or similar) insecticides, it is expected that new mutations (conferring equal or greater resistance, but less of a fitness cost) will evolve. Pyrethroid insecticides target the insect voltage sensitive sodium channel (VSSC) and have been widely used for control of house flies at animal production facilities for more than three decades. There are three Vssc mutations known that cause resistance to pyrethroids in house flies: knockdown resistance (kdr, L1014F), kdr‐his (L1014H) and super‐kdr (M918T + L1014F). Whether or not there are any new mutations in house fly populations has not been examined for decades. We collected house flies from a dairy in Kansas (USA) and selected this population for three generations. We discovered multiple new Vssc alleles, including two that give very high levels of resistance to most pyrethroids. The importance of these findings to understanding the evolution of insecticide resistance, designing appropriate resistance monitoring and management schemes, and the future of pyrethroids for house fly control are discussed.     

拟除虫菊酯对中华按蚊繁殖率和生存力影响的观察报告

用拟除虫菊酯亚致死剂量处理中华按蚊,显示该蚊的生存力和繁殖率降低。以胺菊酯或溴氰菊酯处理中华按蚊,产卵的胚胎发育减慢。溴氰菊酯致死的部分中华按蚊幼虫体长缩短。     

Synergist efficacy of piperonyl butoxide with deltamethrin as pyrethroid insecticide on Culex tritaeniorhynchus (Diptera: Culicidae) and other mosquitoe species

Continuous and indiscriminate use of pesticides, especially in tropical countries for public health or agriculture purpose, has led many vector populations to become resistant to organochlorides, organophosphates, and even to carbamates and pyrethroids. Development of resistance by a vector population has been one of the reasons for the failure of the control measures in many countries. This investigation demonstrates the efficacy of piperonyl-butoxide (PBO) with deltamethrin, as pyrethroid insecticide, against the field-collected mosquitoe larvae of five species, Aedes aegypti, Anopheles culicifacies, An. stephensi, An. vagus, and Culex quinqufasciatus, and two morphological variants of Cx. tritaeniorhynchus (type A from grand pools of Mysore city and type B from rice fields of Mandya district). For testing the synergistic effect of PBO, stock solutions of deltamethrin and PBO were mixed in 1:6 ratio. The synergistic ratio and the percent suppression in deltamethrin tolerance were calculated by using LC(50) values. From the results, it is clear that, PBO is an effective synergist with deltamethrin against all of species undertaken in this investigation. So, it is suggested that PBO is a good synergist in this area for decreasing the use of pesticides in environment in vector control.     

拟除虫菊酯农药暴露对婴儿生长发育的影响

【目的】 探讨拟除虫菊酯农药暴露对婴儿生长发育的影响,为预防儿童农药中毒提供科学依据。 【方法】 选取江苏某县1岁婴儿449名,收集随机尿样检测拟除虫菊酯代谢物顺式-3-(2,2-二氯乙烯基)-2,2-二甲基环丙烷-1-羧酸(cis-Cl₂CA)、反式-3-(2,2-二氯乙烯基)-2,2-二甲基环丙烷-1-羧酸(trans-Cl₂CA)和3-苯氧基苯甲酸(3-PBA)水平,测量婴儿身长、体重、头围、胸围,用“0~6岁儿童发育筛查测验”(DST)评估婴儿智能发育状况,分析两者之间关系。 【结果】 研究对象尿样拟除虫菊酯代谢物cis-Cl₂CA、trans-Cl₂CA和3-PBA检出率分别为70.4%、97.6%和84.2%。按照总拟除虫菊酯浓度P₂₅、P₇₅分为低中高三组,不同暴露水平组之间婴儿的体重、胸围不完全相同,具有统计学意义(P<0.05),但身长、头围和发育商差异无统计学意义。多重线性回归分析亦提示尿拟除虫菊酯的浓度与体重有相关性(P<0.05)。 【结论】 拟除虫菊酯暴露对婴儿体重有一定的影响。