Pest management strategies relying on agrochemicals could be altered by climate change, because of the temperature-dependent toxicity of the compound involved. Many studies have explored the response of targeted pests to pesticide and temperature. Pesticides are seldom strictly selective and also affect nontarget pests. Surprisingly, the way temperature may shape these side effects of pesticides remains overlooked, limiting our understanding of the net impacts of future chemical treatments on the overall damage induced by different pests. We investigated how temperature modulates the response of a major grape insect pest (the tortricid moth Lobesia botrana) to a copper-based fungicide. We examined the lethal (larval survival) and sublethal (larval development, pupal mass, immune parameters) effects of exposure to different concentrations of copper in larval food. We found that copper concentration had negative linear effects on larval development and pupal mass. In addition, copper concentration had biphasic curvilinear effects on total phenoloxidase activity, which is indicative of hormesis (stimulation and inhibition of insect performance at low and high copper concentrations, respectively). Temperature stimulated development, while compromising immunity (total phenoloxidase activity). Significant interaction between copper concentration and temperature was detected for larval survival and phenoloxidase activity: warmer conditions improved pest tolerance to copper through temperature-driven hormesis (larval survival) or by shifting the hormesis-related peak of performance toward higher copper concentrations (phenoloxidase activity). This combination of simple and interactive effects could propagate to populations, communities and agroecosystem, with implications for future management of viticultural pests.

由于所涉及化合物的温度依赖性毒性，气候变化可能会改变依赖农用化学品的害虫管理策略。许多研究探索了目标害虫对农药和温度的反应。农药很少有严格的选择性，也会影响非目标害虫。令人惊讶的是，温度可能影响农药的这些副作用的方式仍然被忽视，这限制了我们对未来化学处理对不同害虫引起的整体损害的净影响的理解。我们研究了温度如何调节主要葡萄害虫（砻蛾Lobesia botrana) 到铜基杀菌剂。我们检查了暴露于幼虫食物中不同浓度铜的致死（幼虫存活）和亚致死（幼虫发育、蛹质量、免疫参数）影响。我们发现铜浓度对幼虫发育和蛹质量有负面的线性影响。此外，铜浓度对总酚氧化酶活性具有双相曲线效应，这表明兴奋作用（分别在低和高铜浓度下对昆虫性能的刺激和抑制）。温度刺激发育，同时损害免疫力（总酚氧化酶活性）。在幼虫存活和酚氧化酶活性方面检测到铜浓度和温度之间的显着相互作用：温暖的条件通过温度驱动的兴奋作用（幼虫存活）或通过将与兴奋作用相关的性能峰值转移到更高的铜浓度（酚氧化酶活性）来提高害虫对铜的耐受性。这种简单和交互作用的组合可以传播到种群、社区和农业生态系统，对未来葡萄栽培害虫的管理产生影响。