Degradation, adsorption and leaching behaviour of triafamone and ethoxysulfuron and their effect on soil enzymes

Rajandeep Kaur

Degradation, adsorption and leaching behaviour of triafamone and ethoxysulfuron and their effect on soil enzymes

Date

2023

Authors

Rajandeep Kaur

Publisher

Punjab Agricultural University

Abstract

Field trials were carried out to compare the degradation of triafamone and ethoxysulfuron in soils of direct seeded (DSR) and transplanted rice (TPR) fields. Half-lives of triafamone ranged from 13.02 to 20.93 and 12.09 to 14.67 days under DSR and TPR conditions, respectively while for ethoxysulfuron half-lives ranged from 11.71 to 15.64 and 9.90 to 12.19 days. Among both the herbicides, triafamone was more persistent in the soil. Metabolite M1 and M2 appeared at 3 and 7 DAA of herbicide and persisted up to 21 and 15 days after application (DAA) of herbicide in DSR and TPR, respectively while E3 appeared at 21 DAA of herbicide and persisted up to 90 and 60 DAA of herbicide in DSR and TPR, respectively. The residues of herbicide at harvest at below the detectable limit (<0.008 µg g-1). Triafamone and ethoxysulfuron had a transitory harmful effect on soil biochemical and microbiological parameters depending herbicide dose. Triafamone and ethoxysulfuron has highest leachability in loamy sand followed by sandy loam and clay loam. Among both the herbicides, ethoxysulfuron was more mobile and leachability increased with increase in rainfall. The adsorption data fitted well in Freundlich equation with KF 1.819±0.07 to 3.319±0.074 and 1.064±0.050 to 2.330±0.020 µg1-1/ng-1ml1/n for triafamone and ethoxysulfuron, respectively. Adsorption increased with increase in OM and clay content of soil. Hysteresis ranged from 0.003 to 0.017 in studied soils indicating that triafamone and ethoxysulfuron was difficult to desorb due to its irreversible binding with soils.

Citation

Rajandeep Kaur (2023). Degradation, adsorption and leaching behaviour of triafamone and ethoxysulfuron and their effect on soil enzymes (Unpublished M.Sc. thesis). Punjab Agricultural University, Ludhiana, Punjab, India.