Analysis Center, Residue Laboratory, Jiangsu Pesticide Research Institute, Nanjing, People's Republic of China.
State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai, People's Republic of China.
Food Addit Contam Part A Chem Anal Control Expo Risk Assess. 2021 Dec;38(12):2102-2115. doi: 10.1080/19440049.2021.1959070. Epub 2021 Aug 18.
Strawberries are widely cultivated and highly consumed globally, but pests and diseases can severely affect yields. Phenamacril and difenoconazole are high-efficacy pesticides and the mixture of these two pesticides offers a satisfactory option for disease control. In this study, an optimised QuEChERS method combined with dispersive solid-phase extraction purification before injection for simultaneously determining the residues of phenamacril-difenoconazole mixture on strawberries was developed and validated using ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). Average recoveries of phenamacril and difenoconazole in the strawberry matrices ranged from 100% to 104% and 99% to 104%, with relative standard deviations of 2.6%-5.3% and 2.2%-5.5%, respectively. The degradation half-lives of phenamacril and difenoconazole were 3.5-6.6 days and 2.2-3.4 days on strawberries, respectively. Final residues of phenamacril and difenoconazole on strawberries at eight different cultivation regions were 0.033-0.66 mg kg and <0.02-0.089 mg kg after spraying at the maximum dosage recommended by the company of 300 mg a.i. kg twice, respectively. Overall, this study is the first report of phenamacril and difenoconazole residue analysis in strawberries. Therefore, it could provide the reference data for safe management and proper use of phenamacril and difenoconazole in China.
草莓在全球范围内广泛种植和消费，但病虫害会严重影响产量。苯霜灵和氟菌唑是高效农药，将这两种农药混合使用是控制病害的满意选择。本研究采用优化的 QuEChERS 方法结合分散固相萃取净化前处理，建立了超高效液相色谱-串联质谱（UPLC-MS/MS）同时测定草莓中苯霜灵-氟菌唑残留量的方法，并对其进行了验证。苯霜灵和氟菌唑在草莓基质中的平均回收率为 100%-104%和 99%-104%，相对标准偏差为 2.6%-5.3%和 2.2%-5.5%。苯霜灵和氟菌唑在草莓上的降解半衰期分别为 3.5-6.6 天和 2.2-3.4 天。在 8 个不同种植区，按推荐的最大施用量 300 mg a.i. kg 两次喷雾后，草莓中苯霜灵和氟菌唑的最终残留量分别为 0.033-0.66 mg kg 和 <0.02-0.089 mg kg。总的来说，本研究首次报道了草莓中苯霜灵和氟菌唑的残留分析。因此，可为中国苯霜灵和氟菌唑的安全管理和合理使用提供参考数据。
