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The study on dissipation and harvest time residues of pyrazosulfuron-ethyl 0.75% and pretilachlor 30% WG after foliar application at seedling stage in rice at two doses 2000 g/ha (15 + 600 g/ha) and 4000 g/ha (30.0 + 1200 g/ha) was conducted at Integrated Farming System Research Station, Kerala Agricultural University, Thiruvananthapuram, Kerala. The pyrazosulfuron-ethyl and pretilachlor residues were estimated using LCMS/MS. The mean initial deposit of pyrazosulfuron-ethyl at recommended and double the recommended doses were 0.18 and 0.48 mg/kg, respectively. The residue dissipated with time and reached below limit of quantification (LOQ) of 0.01 mg/kg after 5 days in the recommended dose and 7 days in double the recommended dose. The mean initial deposit of pretilachlor at recommended and double the recommended dose were 8.84 and 15.50 mg/kg, respectively. The residue dissipated with time and reached below LOQ of 0.05 mg/kg within 15 days both in the recommended and double the recommended dose. The half-life values (days) were 1.29 and 1.80 for pyrazosulfuron-ethyl and 1.88, 1.37 for pretilachlor at recommended and double the recommended doses, respectively. In addition, the harvest time residues of pyrazosulfuron-ethyl 0.75% + pretilachlor 30% WG were estimated in samples of rice grain, husk, straw and cropped soil and were found below LOQ.