Dissipation kinetics of imazethapyr and its effect on soil enzymes
Loading...
Date
2020
Authors
Journal Title
Journal ISSN
Volume Title
Publisher
Punjab Agricultural University, Ludhiana
Abstract
Fate of herbicide in soil is greatly affected by several factors viz. soil properties, temperature,
and application rate. The present study assesses the degradation dynamics of imazethapyr in
soils of Punjab under laboratory conditions. The dissipation of imazethapyr followed biphasic
first order kinetics and soil type, application rate and temperature greatly influenced the
dissipation behavior of imazethapyr. The half-life of imazethapyr for the first relatively faster
phase was 5.87 to 7.47 days and it ranged from 76.50 to138.68 days in second relatively
slower phase in studied soils. The adsorptive potential was probably responsible for the
difference in dissipation rate between the studied soils. Degradation rate of imazethapyr
increased with temperature and its half life ranged from 76.50 to138.68, 79.44 to 142.92 and
83.31 to 145.09 days at 25, 35 and 45°C. The presence of imazethapyr metabolites was also
detected in studied soils using LC-MS/MS. Imazethapyr get degraded into three metabolites
which ultimately get mineralized to carbon dioxide as end product. Variation in physicochemical
properties of soils and applied herbicide changed the period of appearance and
persistence of the metabolites. Imazethapyr application has short lived as well as transitory
effect on dehydrogenase activity (DHA), alkaline phosphates activity (APA) and soil
microbial biomass at all application levels but urease activity remains unaffected.
Description
Keywords
Citation
Lovedeep Kaur (2021). Dissipation kinetics of imazethapyr and its effect on soil enzymes (Unpublished M.Sc. thesis). Punjab Agricultural University, Ludhiana, Punjab, India.