哒螨灵在棉花叶片及土壤中的残留和消解动态

Residue and Dissipation Dynamics of Pyridaben in Cotton Leaves and Soil

摘要:

本研究测定干旱地区环境和种植条件下，15%哒螨灵乳剂叶面喷施后在棉花叶片和根系土壤中的残留和消解动态。试验采用4个施药水平处理（450~1 125 mL·hm^-2），各喷施1次，于施药后14 d间隔期内不同时间采集棉花上叶及根系土壤样品，采用QuEChERS方法结合高效液相色谱法对样品进行分析。根据所建立的分析方法，在450~1 125 mL·hm^-2剂量范围内，施药后棉花叶片中哒螨灵的原始沉积量为1.11~2.03 mg·kg^-1，消解半衰期为1.35~1.47 d；土壤中的原始沉积量为0.26~0.56 mg·kg^-1，消解半衰期为2.39~2.92 d，14 d后完全消解，表明哒螨灵在本地区属于易降解农药，大大降低了施用后的环境安全风险。

Abstract:

This study determined the residue and dissipation dynamics of pyridaben in cotton leaves and root soil under arid environmental conditions and local planting systems after foliar application of 15% pyridaben emulsion. Four application rates(450-1 125 mL/ha) were set, with one spray application per treatment. Cotton upper leaves and root soil samples were collected at different times within 14 days after application. Samples were analyzed using the QuEChERS method combined with high-performance liquid chromatography (HPLC). According to the established analytical method, within the application rate range of 450-1 125 mL/ha, the initial deposition of pyridaben in cotton leaves after application was 1.11-2.03 mg·kg^-1, with a dissipation half-life of 1.35-1.47 days. In soil, the initial deposition was 0.26-0.56 mg·kg^-1, with a dissipation half-life of 2.39-2.92 days. Pyridaben was completely dissipated in soil after 14 days. These results indicate that pyridaben is an easily degradable pesticide in this region, which significantly reduces the environmental safety risk after application.