Abstract:
To determine the residual digestion and subcellular distribution of acetamiprid and emamectin benzoate in apricot fruit during development and their correlation. Samples of apricot fruit at different development stages were collected from 6 experimental sites in Xinjiang Uygur Autonomous Region after spraying 5% acetamiprid emulsion with 2000 times liquid and 3% emamectin benzoate microemulsion with 5000 times liquid, respectively. The samples were collected by ultra-high performance liquid chromatography-tandem mass spectrometry and differential centrifugal method. The contents of acetamiprid and emamectin benzoate in apricot fruit and its cell wall, organelles and soluble components were analyzed, and the dynamic change of residue digestion of acetamiprid and emamectin benzoate in apricot fruit during the development period was discussed. The results showed that the digestion kinetics of acetamiprid and emamectin benzoate were consistent with the first-order kinetic model, and the half-lives were 0.709-2.656 d and 0.266-0.779 d, respectively. Among the 3 subcellular components, the residue level of acetamiprid in apricot fruit was significantly positively correlated with the residue level of acetamiprid in cell wall and organelle components, with the correlation coefficients 0.711 and 0.729, respectively. The content of emamectin benzoate in apricot fruit was significantly positively correlated with the residue level of emamectin benzoate in cell wall components, with the correlation coefficient 0.520. It can be concluded that cell wall and organelle components are the main components that affect the residual change of acetamiprid in apricot fruit, and cell wall components are the main components that affect the residual change of emamectin benzoate in apricot fruit. The results can lay a theoretical basis for further studies on the metabolism and absorption process of pesticides in apricot fruit.