Metabolism Of Flumorph And SYP-9080 In Cucumber

When pesticides are applied to plants as exogenous substances,the plants undergo metabolism and degradation processes in the body while they are being absorbed,forming some potentially toxic metabolites and accumulated residues,which are transferred to environmental organisms through different routes.and posing potential threats to human health and environmental safety.Based on UFLC-QTRAP-MS system and LightSight software,the metabolism of flumorph and SYP-9080 in cucumber plants were studied.The potential metabolites were identified,and the trace analysis methods for pesticide prototypes and its main metabolites were established to clarify the dynamic changes of pesticides in plants,which provide scientific basis for systematic evaluation of pesticide safety and guidance of scientific and rational drug use.The data was collected by the multiple reaction monitoring scan,precursor ion scan and neutral loss experiment.Combining with the mass spectrometry cleavage rules of the parents and analogs,10 metabolites were identified in the flumorph samples,including 8 phase I and2 phase II metabolites.Major metabolic behaviors included oxidation,demethylation,N-dealkylation,defluorination,and combining with glucose.Two phase I metabolites were identified from cucumber plants treated with SYP-9080 and the main metabolic pathways were demethylation and N-dealkylation.After a single application of flumorph 20%WP at the dose of 150 g ai/hm²,the content in the plant increased first and then decreased,and the digestion rate of the flumorph reached98.3%at 38 d after application.The first-order kinetic equation was C_t=46.492e^-0.11t,R²=0.9905,and the half-live was 6.30 d.The main metabolites were FML-C₄H₆O,FML-CH₂+glc and FML+O.10%SYP-9080 SC was applied to cucumber plants at a dose of 30 g a.i./hm².Within 7 d after application,SYP-9080 maintained a high level in the plants.After 24 d,the concentration showed a downward trend.After 30 d,the digestion rate reached more than90%.With the collection time changed,The content in the plants gradually decreased during the period.The disspation dynamics fitted with the first-order kinetics equation:C_t=15.632e^-0.126t,R²=0.8199,and half-life was 5.50 d.