Beijing Advanced Innovation Center for Food Nutrition and Human Health, College of Food Science & Nutritional Engineering, China Agricultural University, Beijing, 100083, China; Department of Food and Biological Engineering, Beijing Vocational College of Agriculture, Beijing, 102442, China.
Beijing Key Laboratory of New Technology in Agricultural Application, National Demonstration Center for Experimental Plant Production Education, Beijing University of Agriculture, Beijing, 102206, China.
Food Chem. 2019 Jun 30;284:73-79. doi: 10.1016/j.foodchem.2019.01.094. Epub 2019 Jan 22.
The dissipation kinetics of a combined use of procymidone and thiamethoxam, and their impact on the biodiversity and pathogen on surface of tomatoes were studied. The half-lives of procymidone and thiamethoxam, used either on their own or in combination with each other, were 2.94 or 3.26 days and 2.41 or 2.67 days, respectively. The residues dropped below the maximum residue limit (MRL) after 7 or 10 days (MRL 2 mg·kg for procymidone), and 10 or 14 days (MRL 0.2 mg·kg for thiamethoxam), respectively. The phylum Bacteroidetes, Cyanobacteria, and Proteobacteria, were dominantly present in all studied samples. The genus Escherichia-Shigella was found and exposed to the dissipation of procymidone (r = -0.9209 for procymidone on its own, and r = -0.8611 for procymidone in combination with thiamethoxam). These results will contribute to establish adequate monitoring of pesticides residues and their incorporation in surface ecology and pathogen management strategies in tomatoes.
本研究考察了菌核净和噻虫嗪联合使用时的消解动态及其对番茄表面生物多样性和病原菌的影响。单独使用或联合使用时，菌核净和噻虫嗪的半衰期分别为 2.94 天和 2.41 天、3.26 天和 2.67 天。残留量在 7 天或 10 天（菌核净的最大残留限量（MRL）为 2mg·kg）后降至 MRL 以下，在 10 天或 14 天（噻虫嗪的 MRL 为 0.2mg·kg）后降至 MRL 以下。在所有研究样本中，厚壁菌门、蓝藻门和变形菌门均占优势。发现并暴露于菌核净消解的埃希氏-志贺氏菌属（r = -0.9209，单独使用菌核净时；r = -0.8611，菌核净与噻虫嗪联合使用时）。这些结果将有助于建立对农药残留的充分监测，并将其纳入番茄表面生态学和病原菌管理策略中。
