Project Coordinating Cell, Pesticide Residue Laboratory, All India Network Project on Pesticide Residues, ICAR-Indian Agricultural Research Institute, New Delhi, India.
Project Coordinating Cell, Pesticide Residue Laboratory, All India Network Project on Pesticide Residues, ICAR-Indian Agricultural Research Institute, New Delhi, India.
Regul Toxicol Pharmacol. 2019 Nov;108:104471. doi: 10.1016/j.yrtph.2019.104471. Epub 2019 Sep 4.
Multi-locational supervised field trials were conducted in different agro-climatic regions in India to study dissipation of trifloxystrobin and tebuconazole in tomato after spraying a combination formulation (trifloxystrobin 25% + tebuconazole 50%, 75WG) at recommended doses: (i) single (trifloxystrobin 87.5 g a.i. ha + tebuconazole 175 g a.i. ha) and (ii) double (trifloxystrobin 175 g a.i. ha + tebuconazole 350 g a.i. ha). Fruit samples were extracted with ethyl acetate using a modified QuEChERS method. The residues (parent fungicides + metabolite) were analyzed and confirmed by GC-ECD and GC-MS, respectively. The half-life (t) of trifloxystrobin and tebuconazole in tomato varied from 1.08 to 1.72 and 1.13 -to 1.64 days at single; and 1.27 to 2.13 and 1.24 to 1.96 days at double dose, respectively. Since maximum residue limit (MRL) at pre-harvest interval (PHI) of 5 days is impractical, as tomato is usually harvested and consumed almost everyday after the last spray, the risk assessment was performed at minimum PHI of 1 day. Accordingly, on the basis of supervised field trial data and using OECD MRL calculator, MRL of 0.5 and 1.5 mg kg at single dose were proposed for trifloxystrobin and tebuconazole in/on tomato, respectively.
在印度不同的农业气候区进行了多点监督田间试验，以研究在推荐剂量下（i）单剂（25%三氟苯唑+50%戊唑醇，75 可湿性粉剂，87.5 克三氟苯唑活性成分/公顷+175 克戊唑醇活性成分/公顷）和（ii）双剂（175 克三氟苯唑活性成分/公顷+350 克戊唑醇活性成分/公顷）喷雾后，三氟苯唑和戊唑醇在番茄中的消解情况。使用改良的 QuEChERS 方法，用乙酸乙酯提取果实样本。用 GC-ECD 和 GC-MS 分别分析和确认残留（母体杀菌剂+代谢物）。三氟苯唑和戊唑醇在番茄中的半衰期（t）在单剂下分别为 1.08-1.72 天和 1.13-1.64 天；在双剂量下分别为 1.27-2.13 天和 1.24-1.96 天。由于在 5 天的收获前间隔（PHI）时的最大残留限量（MRL）不切实际，因为番茄通常在最后一次喷雾后几乎每天都会被收获和食用，因此在最小 PHI 为 1 天时进行了风险评估。因此，根据监督田间试验数据并使用经合组织 MRL 计算器，建议在番茄中单剂三氟苯唑和戊唑醇的 MRL 分别为 0.5 和 1.5mg/kg。
