Field Evaluation and Residue Analysis of Three Insecticides Against <i>Liriomyza trifolii</i> (Burgess) in Common Bean ( <i>Phaseolus vulgaris</i> L.) Using QuEChERS Method and Liquid Chromatography‐Electrospray Ionization‐Mass Spectrometry/MS

Abstract

In Egypt, the common bean ( Phaseolus vulgaris L.) is commonly grown for export and local consumption. One of the most significant insect pests that invades this important crop is the leaf miner, Liriomyza trifolii (Burgess) (Diptera: Agromyzidae), which damages bean plants by tunneling into leaves, disrupting photosynthesis, and potentially causing defoliation and plant death. Effective control of this pest is challenging as larvae develop within leaf tissues, reducing the effectiveness of contact insecticides. This article presents a field evaluation of three insecticides—cyantraniliprole, emamectin benzoate, and dinotefuran (as standard treatment)—against L. trifolii on common bean plants. In addition, the dissipation patterns and residue dynamics of both cyantraniliprole and emamectin benzoate insecticides in bean pods, leaves, and soil were analyzed using the QuEChERS technique and liquid chromatography‐electrospray ionization‐mass spectrometry/MS. Our results showed that cyantraniliprole exhibited the highest efficacy and longest residual activity against L. trifolii , followed by dinotefuran and emamectin benzoate. Residue analysis confirmed that cyantraniliprole persisted longer in plant tissues compared to the emamectin benzoate but remained within safe limits. These findings suggest that cyantraniliprole is a promising choice for managing L. trifolii infestations in common bean crops in Egypt, offering effective pest control without compromising safety.