Assessment of variable agroclimatic impact on dissipation kinetics of ready-mix fungicide formulation in green chili for harmonization of food safety

Multi-locational supervised field trials were conducted with ready-mix formulation of two fungicides, tricyclazole (18%) + mancozeb (62%) in green chili (Capsicum annuum) to assess the impacts of variable weather conditions on the residual profile for more realistic food safety evaluation. Liquid chromatography-Electrospray Ionization-Mass Spectrometry [LC-ESI(+ve)-MS/MS] and Ultraviolet Visible (UV-Vis) spectrophotometer have been employed for tricyclazole and mancozeb determination respectively. Tricyclazole was extracted in acetone: water (9:1) with dispersive solid phase extraction (d-SPE) cleaned up whereas mancozeb was digested in concentrated HCl and SnCl₂. The developed method was successfully validated as per SANTE/12682/2019 guidelines. On green chilli, 225 + 775 g a.iha⁻¹(active ingredient per hectare) (1250 g formulation-ha⁻¹) and 450 + 1550 g a.iha⁻¹ (active ingredient per hectare) (2500 g formulation-ha⁻¹) of a combined formulation of tricyclazole (18%) and mancozeb (62%), WP, were employed as the recommended dose (T1) and double the recommended dose (T2), respectively. The initial depositions of tricyclazole were varied from 0.47 to 0.74 and 1.30–2.33 mg kg⁻¹ and for mancozeb ranged from 0.93 to 1.31 and 2.68–4.13 mg kg⁻¹ at the respective doses. The respective half-life (days) values of tricyclazole and mancozeb were 1.65–2.41 and 1.20–1.66 irrespective of doses and locations. The maximum residue limit (MRL) of 0.05 mg kg⁻¹ for tricyclazole in green chili has been proposed for Food Safety and Standard Authority of India (FASSAI), India with recommended pre-harvest intervals (PHI) of 12 days. The third location (Anand Agricultural University, Anand, Gujarat) with the least rainfall and humidity has recorded the highest initial deposition, persistence, half-life, and PHI. The ready-mix fungicide has also increased fresh yield up to 22–34%. All these data may provide valuable information on the safe use and promotion of fungicides mixture.