The aim of this study was to investigate the possibility of eradicating the red imported fire ant, Solenopsis invicta Buren, in the hot, humid and rainy conditions of northern Taiwan. Thirteen hectares of the Shihmen ...The aim of this study was to investigate the possibility of eradicating the red imported fire ant, Solenopsis invicta Buren, in the hot, humid and rainy conditions of northern Taiwan. Thirteen hectares of the Shihmen Reservoir have been infected with these ants, with a total of 1 578 mounds. Pyriproxyfen was applied at a rate of 2 kg/hectare each season, for a total of four seasons. Surveys using visual examination, bait traps, as well as the population index method showed that the brood, the reproductive ants, and the worker ants within the nests were all significantly reduced 1 month after the first application of pyriproxyfen. Four months after the initial application there were no more brood or reproductive ants. After 8 months there were no longer any active mounds left, and 12 months later there were no more worker ants. After monitoring for 1 more year, it was ascertained that the red imported fire ants were eradicated. The percentages of decrease after 2, 4 and 6 months of treatment were 57.4%, 80.5%, and 98.2%, respectively.展开更多
[目的]探索茶叶中啶虫脒和吡丙醚的残留行为和可能存在的膳食摄入风险。[方法]以27%啶虫脒·吡丙醚可分散液剂按32.55 g a.i./hm^(2)进行叶面均匀喷雾施药1次,进行8个地域的规范残留试验。采用QuEChERS方法进行样品前处理,超高液相...[目的]探索茶叶中啶虫脒和吡丙醚的残留行为和可能存在的膳食摄入风险。[方法]以27%啶虫脒·吡丙醚可分散液剂按32.55 g a.i./hm^(2)进行叶面均匀喷雾施药1次,进行8个地域的规范残留试验。采用QuEChERS方法进行样品前处理,超高液相色谱串联质谱法对茶叶中的啶虫脒和吡丙醚残留量进行定量分析,研究啶虫脒和吡丙醚农药的最终残留和消解动态,评价啶虫脒和吡丙醚对中国人群的急性和慢性膳食摄入风险。[结果]田间试验表明:啶虫脒和吡丙醚的消解符合一级动力学方程,啶虫脒在重庆和安徽2地茶鲜叶中的降解半衰期为5.00、5.91 d,吡丙醚在2地的半衰期为1.26、5.48 d;末次施药后14、21 d,啶虫脒在茶鲜叶和茶干叶中的残留量为<LOQ~0.90、0.02~3.19 mg/kg,吡丙醚为<LOQ~1.13、<LOQ~0.37 mg/kg;膳食风险评估结果表明,茶叶中啶虫脒和吡丙醚对18岁及以上男女人群健康都处于安全水平。[结论]在茶树上使用27%啶虫脒·吡丙醚可分散液剂,施用剂量不超过32.55 g a.i./hm^(2),施药1次,安全间隔期为14 d,对成年人群的残留风险处于安全水平。展开更多
文摘The aim of this study was to investigate the possibility of eradicating the red imported fire ant, Solenopsis invicta Buren, in the hot, humid and rainy conditions of northern Taiwan. Thirteen hectares of the Shihmen Reservoir have been infected with these ants, with a total of 1 578 mounds. Pyriproxyfen was applied at a rate of 2 kg/hectare each season, for a total of four seasons. Surveys using visual examination, bait traps, as well as the population index method showed that the brood, the reproductive ants, and the worker ants within the nests were all significantly reduced 1 month after the first application of pyriproxyfen. Four months after the initial application there were no more brood or reproductive ants. After 8 months there were no longer any active mounds left, and 12 months later there were no more worker ants. After monitoring for 1 more year, it was ascertained that the red imported fire ants were eradicated. The percentages of decrease after 2, 4 and 6 months of treatment were 57.4%, 80.5%, and 98.2%, respectively.
