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Author: Ritu Devi × Start date: 2010 × Thesis Type: M.Sc ×
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    ThesisItemOpen Access
    Persistence and leaching behaviour of halosulfuron-methyl in soil
    (CCSHAU, 2017) Ritu Devi; Duhan, Anil
    A laboratory experiment was conducted in Agrochemicals Residues Testing Laboratory, Department of Agronomy, Chaudhary Charan Singh Haryana Agricultural University to study the persistence behaviour and leaching potential of halosulfuron-methyl residues in sandy loam and clay loam soil. Halosulfuron-methyl (Sempra75 WG) at single and double dose, i.e., 67.5 and 135 g a.i./ha, was applied in soil taken in plastic pots to study the persistence behaviour. Soil samples were collected periodically on 0 (1h), 1, 3, 7, 10, 15, 30 and 45 days after treatments. In leaching experiment, halosulfuron-methyl was applied at 50 μg (single dose) and 100 μg (double dose) in both soils packed in plexi glass columns. Prior to taking up analysis of test samples recovery experiments using different sample preparation techniques (Matrix solid phase dispersion (MSPD), Liquid-solid extraction (LSE) and QuEChERS with slight modification) were optimized for both soils at different fortification levels of 0.005, 0.01 and 0.1 μg/g. Maximum recoveries (85.5 to 94.5%) were obtained by using QuEChERS with PSA and without MgSO4. Residues were estimated by HPLC coupled with Quadrupole Dalton Mass Detector (QDa). Limit of detection and quantification were 0.001 and 0.005 μg/g, respectively for both soils. Dissipation followed a first order rate kinetics with half-life of 9.4 and 10.7 days in sandy loam soil and in case of clay loam, 8.4 and 10.3 days at both the doses, respectively. The residues were below detectable limit after 45 days for both the treatments. Leaching experiments were carried out in laboratory under both continuous and discontinuous flow conditions. The residues of halosulfuron-methyl were retained up to soil depth of 35-40 cm in both soil types at single and double dose under continuous and discontinuous flow. The residues were detected in leachate fractions of both soils and doses under continuous as well as discontinuous flow conditions; hence there might be a risk of sideway and lateral movement of residues.