Dissipation kinetics and risk assessment of fluopyram and tebuconazole in mango (Mangifera indica)

Abstract

ABSTRACTThe combination formulation of fluopyram and tebuconazole is used for control of fungal diseases and post-harvest disease management of mango. Dissipation study of the fungicides on mango was carried out after giving applications of fluopyram +tebuconazole at the standard and double doses of 150 + 150 and 300 + 300 g active ingredient hectare−1 (g a.i. ha−1), respectively. Fluopyram residues on mango were 0.8 and 0.9 mg kg−1 and tebuconazole residues, 0.308 and 0.4 mg kg−1 after three and four applications at the standard dose. At double dose treatment the residue levels for fluopyram were 1.266 and 1.453 mg kg−1 and tebuconazole, 0.681 and 0.853 mg kg−1, respectively. Residue dissipation in mango fruits followed first order rate kinetics and the half-life (DT50) were 4.3–5.4 days for fluopyram and 3–3.8 days for tebuconazole. Faster dissipation of the fungicides was observed after the fourth treatment which directly correlated to higher rainfall during that period. The combined residues of fluopyram+tebuconazole reduced to below their maximum residue limits (MRLs) within 36–38 days. Dietary risk assessment on human health indicated that fluopyram and tebuconazole application to mango is unlikely to pose risk to human beings. This study gives valuable information on the judicious use of this combination formulation on mango, especially towards harvest.