Persistence and dissipation of fluopicolide in/on grape berries and soil under semi arid tropical climatic conditions of India.

Fluopicolide, a relatively new fungicide is used for control of downy mildew of grape. Persistence study of fluopicolide was carried out on grape berries following treatment of the combination product, fluopicolide 4.44% + fosetyl aluminium 66.7% (Profiler 71.14 WG) at the recommended and double the recommended dose of 2.5 and 5.0 kg ha⁻¹. Four treatment sprays were given at 15 day intervals, starting from 1 month after pruning of the vines. Residues of fluopicolide in grape berries were estimated on 0 (1 h), 1, 3, 5, 7, 10, 15, 20, 25, 30 day and at harvest (64 days after the last spray application). The initial residue deposits of fluopicolide on grape berries were 0.58 and 1.32 mg kg⁻¹ from treatment at the recommended and double dose, respectively. Dissipation of fluopicolide residues was a slow process. After 30 days of treatment, 0.068 and 0.204 mg kg⁻¹ of residues still remained in the berries from treatment at the recommended and double dose, respectively. Fluopicolide residues in grape berries dissipated with the half-life of 10.2 and 12.3 days. Residues in grape berries and soil at harvest were below the quantifiable limit of 0.01 mg kg⁻¹ from both the treatments.