In Argentina,Loliumspp. occur in 40% of winter cereal crops from the Pampas. Several years ago, cases of glyphosate-resistant perennial ryegrass (Lolium perenneL.) were detected, and the use of acetyl-CoA carboxylase (ACCase)-inhibiting herbicides to eradicate these plants has been considered. The aim of this study was to evaluate the sensitivity of a putative pinoxaden-resistantL. perennepopulation to ACCase-inhibiting herbicides. Around 80% of plants from the putative resistant population survived at a recommended dose of pinoxaden, and they produced viable seeds. The resistance indices (RIs) to pinoxaden were 5.1 and 2.8 for plant survival and seed production, respectively. A single point mutation that conferred a Asp-2078-Gly substitution in ACCase was the source of the resistance. To match the plant control achieved in the susceptible population, the resistant population required 5.4- and 10.4-fold greater doses of clethodim and quizalofop, respectively. RIs for viable seed production when treated with clethodim and quizalofop were 3.3 and 6.6, respectively. The Asp-2078-Gly mutation endowed significant levels of resistance to pinoxaden, clethodim, and quizalofop. For three herbicides, the level of resistance of a pinoxaden-resistantL. perennepopulation to ACCase inhibitors was evaluated, based on an evaluation of dose response for plant survival and seed production. The RIs were higher for plant survival than for seed production. In Argentina, the selection pressure associated with clethodim and haloxifop preplant application and pinoxaden use on wheat (Triticum aestivumL.) and barley (Hordeum vulgareL.) crops, would have favored the propagation of the Asp-2078-Gly mutation with its associated resistance.

中文翻译：

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阿根廷多年生黑麦草 (Lolium perenne) 靶位点突变对乙酰辅酶 A 羧化酶抑制除草剂的交叉抗性

在阿根廷，黑麦草spp. 潘帕斯草原 40% 的冬季谷类作物中发生。几年前，抗草甘膦多年生黑麦草案例（黑麦草L.) 被检测到，并且已经考虑使用抑制乙酰辅酶A 羧化酶 (ACCase) 的除草剂来根除这些植物。本研究的目的是评估推定的匹诺沙丁耐药性的敏感性L. perenneACCase抑制除草剂的人群。大约 80% 的假定抗性种群的植物在推荐剂量的匹诺沙登下存活，并且它们产生了有活力的种子。植物存活和种子生产对匹诺沙丁的抗性指数 (RIs) 分别为 5.1 和 2.8。赋予 ACCase 中 Asp-2078-Gly 取代的单点突变是抗性的来源。为了与易感人群中实现的植物控制相匹配，抗性人群分别需要 5.4 倍和 10.4 倍剂量的烯草酮和喹唑啉。当用烯草酮和喹草灵处理时，可存活种子生产的 RI 分别为 3.3 和 6.6。Asp-2078-Gly 突变赋予了对匹诺沙丁、烯草酮和喹唑啉的显着水平的抗性。对于三种除草剂，L. perenne基于对植物存活和种子生产的剂量反应的评估，评估了群体对 ACCase 抑制剂的影响。植物存活的 RI 高于种子生产的 RI。在阿根廷，种植前施用烯草酮和氟噻草胺以及在小麦上使用匹诺沙丁的选择压力（小麦L.) 和大麦 (大麦L.) 作物，将有利于 Asp-2078-Gly 突变及其相关抗性的传播。