Australian Herbicide Resistance Initiative, School of Plant Biology, Institute of Agriculture, University of Western Australia, Crawley, WA, Australia.
Pest Manag Sci. 2012 May;68(5):757-63. doi: 10.1002/ps.2323. Epub 2012 Jan 30.
Hordeum populations are becoming increasingly difficult to control in cropping fields. Two herbicide-resistant H. leporinum populations were identified during a random crop survey after herbicides were applied. The study aimed to determine the herbicide resistance profile of these H. leporinum biotypes to a range of herbicides used for their control.
Based on dose-response studies, one H. leporinum population was very highly resistant to sulfosulfuron and sulfometuron (both sulfonylurea herbicides) and also displayed low-level resistance to imazamox (an imidazolinone herbicide). Reduced sensitivity of the ALS enzyme was identified with in vitro activity assays. Gene sequence analysis revealed a proline-to-threonine substitution at amino acid position 197 of ALS, which is likely to be the molecular basis for resistance in this population. Herbicide screening also revealed a different H. leporinum population with resistance to the bipyridyl herbicide paraquat.
This study established the first cases of (1) sulfonylurea-to-imidazolinone cross-resistance and (2) field-evolved paraquat resistance in a Hordeum species in Western Australia.
在施用除草剂后，通过随机作物调查发现，大麦属种群越来越难以控制。
基于剂量反应研究，一个大麦属种群对磺酰脲类除草剂啶嘧磺隆和甲磺隆（均为磺酰脲类除草剂）表现出高度抗性，同时对咪唑啉酮类除草剂咪草烟（imidazolinone herbicide）表现出低水平抗性。体外活性测定显示 ALS 酶的敏感性降低。基因序列分析显示 ALS 第 197 位氨基酸由脯氨酸突变为苏氨酸，这可能是该种群抗性的分子基础。除草剂筛选还发现了另一个对吡啶类除草剂百草枯具有抗性的大麦属种群。
本研究首次在西澳大利亚的大麦属物种中发现了（1）磺酰脲类-咪唑啉酮类交叉抗性和（2）田间进化的对百草枯的抗性。
