Andika Ignatius P, Vandervoort Christine, Wise John C
Department of Entomology, Michigan State University, East Lansing, MI 48824, USA.
Pesticide Analytical Laboratory, Michigan State University, 206 Center for Integrated Plant Systems, Michigan State University, East Lansing, MI 48824-1311, USA.
Insects. 2019 Jul 11;10(7):203. doi: 10.3390/insects10070203.
Tart cherry production is challenged by precipitation events that may reduce crop protection against spotted-wing drosophila () (SWD). Due to SWD's devastating impacts on yield, growers are often faced with the option of insecticide reapplication. Semi-field bioassays were used to assess simulated rainfall effects towards adult mortality, immature survival, and residue wash-off from different plant tissues for several compounds. Tart cherry shoots were treated with 0, 12.7 or 25.4 mm of simulated rainfall and infested with SWD for 5 days. Adult mortality was recorded 1, 3, and 5 days after shoots were infested, while immature stage individuals were counted 9 days after the first infestation day. All insecticides demonstrated higher adult mortality and lower immature survival compared with the untreated control at 0 mm of rainfall. Adult mortality and immature survival caused by phosmet, zeta-cypermethrin, and spinetoram were adversely affected by simulated rainfall. In all bioassays, acetamiprid was the least affected by simulated rainfall. Residue analysis demonstrated phosmet and spinetoram residues to be the most sensitive to wash-off. This study demonstrates different rainfall effects on SWD control for several compounds. This information may provide a basis for making an informed decision on whether reapplication is required.
酸樱桃生产受到降水事件的挑战，降水可能会降低作物对斑翅果蝇（SWD）的防护能力。由于SWD对产量具有毁灭性影响，种植者常常面临重新施用杀虫剂的选择。半田间生物测定法用于评估模拟降雨对几种化合物的成虫死亡率、未成熟个体存活率以及不同植物组织上残留物冲刷情况的影响。酸樱桃嫩枝接受0、12.7或25.4毫米的模拟降雨处理，并接种SWD 5天。在嫩枝接种后1天、3天和5天记录成虫死亡率，在首次接种日9天后对未成熟阶段的个体进行计数。在降雨量为0毫米时，与未处理的对照相比，所有杀虫剂的成虫死亡率更高，未成熟个体存活率更低。谷硫磷、高效氯氟氰菊酯和多杀霉素导致的成虫死亡率和未成熟个体存活率受到模拟降雨的不利影响。在所有生物测定中，啶虫脒受模拟降雨的影响最小。残留物分析表明，谷硫磷和多杀霉素的残留物对冲刷最为敏感。本研究证明了模拟降雨对几种化合物防治SWD有不同影响。这些信息可为就是否需要重新施用杀虫剂做出明智决策提供依据。
