Salicylic acid (SA) is a signaling molecule that can induce plant resistance to certain herbivores. Although the role of jasmonic acid in mediating mite-tomato plant interactions has been well studied, the role of salicylic acid has not. This study examined how the application of exogenous SA, via its effects on tomato plant physiology, alters the activity of mite digestive enzymes, mite energy reserves, and mite susceptibility to spirodiclofen. Enzymatic activity—including superoxide dismutase, ascorbate peroxidase, guaiacol peroxidase, polyphenol oxidase, and phenylalanine ammonia-lyase—along with contents of total phenolic, hydrogen peroxide, and total chlorophyll significantly increased in plants 24 h after treatment with 2 mM of SA. In contrast, catalase activity significantly decreased in treated plants, and malondialdehyde content was unaffected. Mites fed on tomato plants treated with SA had significantly lower glutathione S-transferase, esterase, α-amylase, and aminopeptidase activities than those fed on control plants. Energy reserve analyses demonstrated a significant decrease in contents of lipid, protein, and glycogen in mites fed on SA-treated plants, whereas carbohydrate content significantly increased. The LC₅₀ of spirodiclofen was decreased 1.8-fold for Tetranychus urticae fed on SA-treated tomato plants compared to controls. Treatment of adult mites with 2 mM SA on leaf discs did not cause any direct mortality after 24 h. Finally, a greenhouse bioassay confirmed that spider mite mortality following exposure to spirodiclofen was significantly higher on SA plants than on control plants. Mortality of mites exposed to half of the recommended rate of spirodiclofen was similar to those exposed to the recommended rate when they were held on treated plants. These results have valuable implications for T. urticae management programs in tomato production.

水杨酸（SA）是一种信号分子，可以诱导植物对某些草食动物产生抗性。尽管茉莉酸在介导螨-番茄植物相互作用中的作用已得到很好的研究，但水杨酸的作用尚未得到研究。这项研究检查了外源SA的应用如何通过其对番茄植物生理的影响来改变螨消化酶的活性，螨的能量储备以及螨对螺二氯芬的敏感性。用2 mM的SA处理后24小时，植物中的酶活性（包括超氧化物歧化酶，抗坏血酸过氧化物酶，愈创木酚过氧化物酶，多酚氧化酶和苯丙氨酸氨裂合酶）以及总酚，过氧化氢和总叶绿素的含量均显着增加。相反，处理过的植物中的过氧化氢酶活性明显降低，丙二醛含量不受影响。用SA处理的番茄植株的螨虫的谷胱甘肽S-转移酶，酯酶，α-淀粉酶和氨肽酶的活性明显低于对照植株。能量储备分析表明，饲喂SA处理过的植物的螨虫中脂质，蛋白质和糖原的含量显着下降，而碳水化合物的含量显着增加。LC与对照组相比，用SA处理过的番茄植物饲喂的Tetranychus urticae的₅₀份螺双氯芬减少了1.8倍。在叶盘上用2 mM SA处理成年螨在24小时后没有引起任何直接死亡。最后，温室生物测定法证实，在暴露于螺二氯芬后，SA植物上的红蜘蛛死亡率显着高于对照植物。暴露于推荐的螺二氯芬比率一半的螨虫的死亡率与暴露于推荐处理植物的螨虫的死亡率相似。这些结果对番茄生产中荨麻疹的管理计划具有重要意义。