A survey of the prevalence of rigid ryegrass (Lolium rigidum) resistant to ACCase and ALS herbicides was conducted in major-cereal growing regions in the north of Tunisia. Randomly collected ryegrass populations were assessed, using the Syngenta RISQ®test, for resistance to clodinafop-propargyl, iodosulphuron + mesosulphuron and pinoxaden. Of the 177 tested populations, 58% exhibited resistance to clodinafop-propargyl and 52% to iodosulphuron + mesosulphuron, with 40% exhibiting resistance to both herbicides. Significant variations in the frequencies of rigid ryegrass resistant to clodinafop-propargyl and/or iodosulphuron + mesosulphuron were observed between surveyed regions which may be the result of differences in the history of herbicide use. Over 50% of resistant populations contained 60% of resistant plants or more, indicating the extent of resistance evolution in these regions. Our study demonstrates that the extent of resistance to ACCase and ALS-inhibiting herbicides in rigid ryegrass is widespread in major cereal-growing regions of Tunisia. Therefore, weed management must be focused on reducing the frequency of herbicide application, using multiple herbicide mechanisms of action, rotating different modes of action and integrating alternative control options.

中文翻译：

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突尼斯北部谷类作物刚性黑麦草种群对 ACCase 和 ALS 抑制性除草剂的抗性现状

硬质黑麦草患病率调查（黑麦草) 在突尼斯北部的主要谷物种植区进行了对 ACCase 和 ALS 除草剂的抗性研究。使用先正达 RISQ 评估随机收集的黑麦草种群®测试，对炔草酯、碘磺隆+甲磺隆和吡诺沙丁的耐药性。在 177 个测试种群中，58% 对炔草酯具有抗性，52% 对碘磺隆 + 甲磺隆具有抗性，40% 对这两种除草剂均表现出抗性。在调查区域之间观察到对炔草酯和/或碘磺隆+甲磺隆耐药的硬质黑麦草的频率存在显着差异，这可能是除草剂使用历史不同的结果。超过 50% 的抗性种群包含 60% 或更多的抗性植物，表明这些地区的抗性进化程度。我们的研究表明，硬质黑麦草对 ACCase 和 ALS 抑制性除草剂的抗性程度在突尼斯的主要谷物种植区普遍存在。所以，