Rapid Detection of Horseweed and Black Picker Sensitivity Levels to Saflufenacil

ABSTRACT: Resistance to herbicides is one of the main factors responsible for weed control failures. Once uncontrolled and stressed, resistant weeds demand a new application of herbicides from different modes of action, which results in higher monetary costs and environmental impact. Knowledge of weed sensitivity levels to herbicides before making decisions for their management in the field is paramount to increasing the efficiency of integrated weed management. Thus, methods that allow the rapid determination of sensitivity levels can help to the correct recommendation before the application, and thus, favor the greater technical, economic and environmental efficiency of weed management. The objective of this work was to validate a rapid method to detect the levels of sensitivity of black picker (Bidens pilosa) and horseweed (Conyza sumatrensis) to saflufenacil. Dose-response experiments were performed in growth chamber, greenhouse and field. The control provided by different doses of the saflufenacil herbicide was evaluated in each environment, and the results correlated within each species. The results showed a significant positive correlation for the results obtained in growth chamber and greenhouse for black picker and horseweed. These results indicate that the method developed in the growth chamber can replace greenhouse tests for determination of the sensitivity of black picker and horseweed to saflufenacil.

摘要：除草剂抗性是导致杂草防控失败的主要因素之一。若抗性杂草未得到有效防控且处于胁迫状态，则需使用不同作用机制的除草剂进行二次施药，这将提升经济成本并加剧环境影响。在田间制定杂草防控方案前，掌握杂草对除草剂的敏感性水平，对提升综合杂草管理效率至关重要。因此，能够快速测定敏感性水平的方法，有助于在施药前给出正确的用药建议，进而提升杂草防控的技术、经济与环境综合效益。本研究旨在验证一种快速检测三叶鬼针草（black picker，Bidens pilosa）与苏门白酒草（horseweed，Conyza sumatrensis）对沙氟芬（saflufenacil）敏感性水平的方法。本研究在生长箱、温室与田间开展了剂量-反应试验，在各试验环境中评估不同剂量的沙氟芬除草剂对杂草的防控效果，并针对每个物种的试验结果进行相关性分析。结果显示，三叶鬼针草与苏门白酒草在生长箱与温室中得到的试验结果存在显著正相关。上述结果表明，本研究在生长箱中建立的检测方法，可替代温室试验，用于测定三叶鬼针草与苏门白酒草对沙氟芬（saflufenacil）的敏感性水平。