Degradation dynamics of sulfoxaflor in Choy sum plants and soil after seed pelletizing treatment and the effectiveness of this pesticide against Phyllotreta striolata (Fabricius)
Author of the article:XIONG Teng-Fei** LIN Qing-Sheng*** FENG Xia***
Author's Workplace：(Institute of Plant Protection, Guangdong Academy of Agricultural Sciences; Guangdong Provincial Key Laboratory of High Technology for Plant Protection, Guangzhou 510640, China)
Key Words： seed-pelletized; sulfoxaflor; prevention and control effect; degradation dynamics
Abstract： [Objectives] To clarify the degradation dynamics of sulfoxaflor in choy sum (Brassica rapa var. Parachinensis) and its effectiveness against Phyllotreta striolata (Fabricius) after seed pelleting treatment, and to provide a reference for the scientific application of the seed pelleting for cruciferous vegetables. [Methods] The degradation dynamics of sulfoxaflor in the vegetative organs and root soil of choy sum were analyzed by High-performance liquid chromatography (HPLC). [Results] The concentration of sulfoxaflor in soil first increased, then decreased, from 17.03 mg/kg the first day after sowing to 33.87 mg/kg on the 10th day to 0.17 mg/kg at the 31st day. The sulfoxaflor concentration in the roots and leaves of choy sum also first increased, then decreased, from 82.14 mg/kg and 279.64 mg/kg, respectively, on the 4th day, to 156.85 mg/kg and 325.22 mg/kg on the 7th day, before falling to below the detection limit on the 31st day. The concentration of sulfoxaflor in the stem of the choy sum decreased from 81.47 mg/kg on the 4th day to below the detection limit on the 31st day. The results of field experiments show that both numbers of P. striolata and damage to choi sum plants were significantly lower than in the control group. [Conclusion] Pelleting of vegetable seeds with sulfoxaflor is safe for the production of choy sum. This method provides an effective solution for the prevention and control of the P. striolata and the safe production of cruciferous crops.