Henriet F, Deloy S, Pigeon O, Moreau J-M
Pesticide Research Department, Walloon Agricultural Research Centre (CRA-W), rue du Bordia 11, BE-5030 Gembloux, Belgium.
Commun Agric Appl Biol Sci. 2005;70(4):1013-22.
During the 2000-2001 season a field trial was conducted with the aim of quantifying the distribution and persistence of epoxiconazole and kresoxlm-methyl in the different leaf layers of winter wheat plants. In the case of applications before flag leaf emergence, the redistribution of the two active ingredients in the newly formed leaves following the applications was also measured. Allegro (125 g/L epoxiconazole and 125 g/L kresoxim-methyl, SC) was applied at the manufacturer's recommended rate (1 L/ha) either in a single treatment at stages GS32, GS39 and GS59 or in 2, 3 or 4 split applications. Following spraying, leaf samples were collected over time, from each leaf layer, and the two active ingredients were quantified by gas chromatography with electron capture detection (GC-ECD). Fungicide distribution varies according to time of application. A descending gradient through the leaves was observed in the case of application at GS59. When sprayed at stage GS39, on the other hand, the second leaf intercepted more fungicide than the flag leaf. Kresoxim-methyl was found to degrade faster than epoxiconazole. With split treatments, the last spraying appears to be very significant in terms of final fungicide quantities. Redistribution appears possible, especially in the case of epoxiconazole, though in very small quantities.
在2000 - 2001年生长季进行了一项田间试验，目的是量化戊唑醇和醚菌酯在冬小麦植株不同叶层中的分布及持效性。对于在旗叶抽出前施药的情况，还测定了施药后两种活性成分在新形成叶片中的再分布情况。以制造商推荐剂量（1升/公顷）施用爱苗（125克/升戊唑醇和125克/升醚菌酯，悬浮剂），在GS32、GS39和GS59阶段进行单次施药，或进行2次、3次或4次分开施药。喷雾后，随时间从各叶层采集叶片样本，通过带有电子捕获检测的气相色谱法（GC - ECD）对两种活性成分进行定量分析。杀菌剂的分布因施药时间而异。在GS59阶段施药时，观察到叶片中存在自上而下的梯度分布。另一方面，在GS39阶段喷雾时，第二片叶截留的杀菌剂比旗叶更多。发现醚菌酯比戊唑醇降解得更快。对于分开施药处理，就最终的杀菌剂含量而言，最后一次喷雾似乎非常重要。再分布似乎是可能的，尤其是对于戊唑醇，不过量非常小。
