Limited research has focused on factors affecting pesticide losses from ornamental plant production nurseries. This project evaluated the effects of overhead irrigation or simulated rainfall intensity and formulation and application methods on the losses of acephate, bifenthrin, and imidacloprid in drainage water. The liquid formulation of each respective pesticide was applied to individual replicates (potted Ilex cornuta Lindl. & Paxton plant on a drainage collection saucer) as substrate-applied drenches or foliar sprays (acephate and bifenthrin only). Granular formulations of acephate and imidacloprid were spread across the tops of media in pots. After application of treatments, irrigation or simulated rainfall was applied daily for 19 consecutive days at rates of 42.3 ± 4.57, 56.7 ± 7.92, and 95.4 ± 19.47 ml min-1 , and drainage water from individual replicates was collected for analysis. Irrigation or simulated rainfall intensity had no effects on losses of the pesticides under the conditions tested. Concentrations in drainage of all three pesticides were highest from the drench applications, whereas respective foliar spray applications resulted in the lowest active ingredient concentrations in drainage. The percentage of active ingredient lost in drainage water ranged from a minimum of 0.2 ± 0.05% (mean ± SE) for granular acephate to a maximum of 19.5 ± 3.14% (mean ± SE) for the imidacloprid drench. Most pesticide losses occurred within the first 2 d after application of drenches or sprays. Granular formulations had a longer period of release, indicating a risk of loss from overirrigation during an extended period. Results emphasize the need for careful water management after applications.

中文翻译：

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容器化观赏植物排水中特定农药的损失

有限的研究集中于影响观赏植物生产苗圃农药损失的因素。本项目评估了高架灌溉或模拟降雨强度以及配方和应用方法对排水中乙酰甲胺磷、联苯菊酯和吡虫啉损失的影响。将每种相应农药的液体制剂作为基质施用的浸液或叶面喷洒（仅乙酰甲胺磷和联苯菊酯）施用于单独的重复（盆栽 Ilexcornuta Lindl. & Paxton 植物在排水收集碟上）。将乙酰甲胺磷和吡虫啉的颗粒制剂散布在盆中培养基的顶部。施用处理后，连续 19 天每天以 42.3 ± 4.57、56.7 ± 7.92 和 95.4 ± 19.47 ml min-1 的速率施用灌溉或模拟降雨，并收集来自各个重复的排水进行分析。在测试条件下，灌溉或模拟降雨强度对农药的损失没有影响。所有三种农药在排水中的浓度在淋施中最高，而各自的叶面喷洒导致在排水中的活性成分浓度最低。排水中活性成分损失的百分比范围从颗粒乙酰甲胺磷的最小 0.2 ± 0.05%（平均值 ± SE）到吡虫啉淋水的最大 19.5 ± 3.14%（平均值 ± SE）。大多数农药损失发生在喷洒或喷洒后的前 2 天内。颗粒制剂具有较长的释放期，表明在较长时期内有因过度灌溉而损失的风险。