Liu Wenjie, Harrison Dion K, Chalupska Dominika, Gornicki Piotr, O'donnell Chris C, Adkins Steve W, Haselkorn Robert, Williams Richard R
Agricultural Molecular Biotechnology Laboratory, School of Agronomy and Horticulture, University of Queensland, Gatton 4343, Queensland, Australia.
Proc Natl Acad Sci U S A. 2007 Feb 27;104(9):3627-32. doi: 10.1073/pnas.0611572104. Epub 2007 Feb 20.
Grass weed populations resistant to aryloxyphenoxypropionate (APP) and cyclohexanedione herbicides that inhibit acetyl-CoA carboxylase (ACCase; EC 6.4.1.2) represent a major problem for sustainable agriculture. We investigated the molecular basis of resistance to ACCase-inhibiting herbicides for nine wild oat (Avena sterilis ssp. ludoviciana Durieu) populations from the northern grain-growing region of Australia. Five amino acid substitutions in plastid ACCase were correlated with herbicide resistance: Ile-1,781-Leu, Trp-1,999-Cys, Trp-2,027-Cys, Ile-2,041-Asn, and Asp-2,078-Gly (numbered according to the Alopecurus myosuroides plastid ACCase). An allele-specific PCR test was designed to determine the prevalence of these five mutations in wild oat populations suspected of harboring ACCase-related resistance with the result that, in most but not all cases, plant resistance was correlated with one (and only one) of the five mutations. We then showed, using a yeast gene-replacement system, that these single-site mutations also confer herbicide resistance to wheat plastid ACCase: Ile-1,781-Leu and Asp-2,078-Gly confer resistance to APPs and cyclohexanediones, Trp-2,027-Cys and Ile-2,041-Asn confer resistance to APPs, and Trp-1,999-Cys confers resistance only to fenoxaprop. These mutations are very likely to confer resistance to any grass weed species under selection imposed by the extensive agricultural use of the herbicides.
对抑制乙酰辅酶A羧化酶（ACCase；EC 6.4.1.2）的芳氧苯氧丙酸酯（APP）和环己二酮类除草剂产生抗性的禾本科杂草种群，是可持续农业面临的一个主要问题。我们研究了来自澳大利亚北部谷物种植区的9个野燕麦（Avena sterilis ssp. ludoviciana Durieu）种群对ACCase抑制性除草剂的抗性分子基础。质体ACCase中的5个氨基酸替换与除草剂抗性相关：Ile-1,781-Leu、Trp-1,999-Cys、Trp-2,027-Cys、Ile-2,041-Asn和Asp-2,078-Gly（根据黑麦草质体ACCase编号）。设计了一种等位基因特异性PCR检测方法，以确定这些5种突变在疑似具有ACCase相关抗性的野燕麦种群中的流行情况，结果是，在大多数但并非所有情况下，植物抗性与这5种突变中的一种（且仅一种）相关。然后，我们使用酵母基因替换系统表明，这些单点突变也赋予了小麦质体ACCase除草剂抗性：Ile-1,781-Leu和Asp-2,078-Gly赋予对APPs和环己二酮类除草剂的抗性，Trp-2,027-Cys和Ile-2,041-Asn赋予对APPs的抗性，而Trp-1,999-Cys仅赋予对精恶唑禾草灵的抗性。在除草剂广泛农业使用所施加的选择压力下，这些突变很可能赋予任何禾本科杂草物种抗性。
