Allan Sandra A, Kline Daniel L, Walker Todd
USDA/ARS, Gainesville, FL 32608, USA.
J Am Mosq Control Assoc. 2009 Sep;25(3):338-46. doi: 10.2987/09-5854.1.
The use of pesticide-treated vegetation as a barrier for control of nuisance and disease-bearing mosquitoes has become an option for mosquito management for home owners and public health and mosquito control professionals. Potted wax myrtle and azalea plants were treated with bifenthrin (0.79% AI) at maximum label rate using backpack and electrostatic sprayers and exposed to various treatments that could affect the residual degradation of the applied pesticides. Treatments included leaf aspect, simulated rainfall, shade, and natural sun exposure with the residual effectiveness of leaves examined in tarsal contact Petri dish assays using laboratory-reared Aedes aegypti. There was no significant difference in efficacy between the adaxial (top) or abaxial (bottom) surfaces of electrostatically or backpack-treated leaves. Significant differences existed between application method, plant species, and exposure with most significant effects between weeks 1 and 4. Simulated heavy rainfalls applied 3 times weekly reduced knockdown by leaves treated with electrostatic and backpack methods with reductions seen as soon as 1 wk after treatment. Reductions were seen with both wax myrtle and azalea leaves and after 1, 4, and 24 h contact of mosquitoes to leaves. Placement of plants with full exposure to sunlight also significantly reduced efficacy compared to plants placed in the shade. Differences were observed most often for 4 and 24 h knockdown counts, and significant decreases were seen from week 4 onwards. Clearly factors such as rain and exposure to sun impact degradation of efficacy of bifenthrin-treated vegetation in the field. Degradation of bifenthrin efficacy was slowest in sites protected from rain and sun, which coincide with preferred resting site locations for many mosquito species.
使用经过杀虫剂处理的植被作为控制滋扰性和携带疾病蚊子的屏障，已成为房主以及公共卫生和蚊虫控制专业人员进行蚊虫管理的一种选择。使用背负式和静电喷雾器，以最大标签剂量用联苯菊酯（0.79%有效成分）处理盆栽杨梅和杜鹃花植物，并使其接受各种可能影响所施用农药残留降解的处理。处理包括叶片朝向、模拟降雨、遮荫以及自然阳光照射，使用实验室饲养的埃及伊蚊通过跗节接触培养皿试验来检测叶片的残留效果。静电处理或背负式处理叶片的正面（顶部）或背面（底部）在药效上没有显著差异。施药方法、植物种类和暴露情况之间存在显著差异，在第1周和第4周之间影响最为显著。每周3次的模拟暴雨降低了用静电和背负式方法处理的叶片的击倒率，处理后1周就出现了降低。杨梅叶和杜鹃叶以及蚊子与叶片接触1、4和24小时后都出现了降低。与置于阴凉处的植物相比，完全暴露在阳光下的植物的药效也显著降低。在4小时和24小时的击倒计数中最常观察到差异，从第4周起出现显著下降。显然，降雨和阳光照射等因素会影响田间联苯菊酯处理植被药效的降解。在免受雨水和阳光影响的地点，联苯菊酯药效的降解最慢，而这些地点与许多蚊虫种类喜欢的栖息地点相吻合。
