College of Plant Protection, Nanjing Agricultural University, Nanjing 210095, China; Key Laboratory of Integrated Pest Management on Crops in East China (Nanjing Agricultural University), Ministry of Agriculture, China.
Dow Agrosciences, Shanghai 201210, China.
Pestic Biochem Physiol. 2017 Nov;143:306-311. doi: 10.1016/j.pestbp.2016.11.001. Epub 2016 Nov 12.
Chinese sprangletop (Leptochloa chinensis (L.) Nees) is a serious grass weed in rice paddies. In some areas, L. chinensis has become resistant to the herbicide cyhalofop-butyl because of its frequent and extensive use over the past five years. In this study, whole-plant dose-response assays were conducted, and a L. chinensis population (ZHYH) had a 75.8-fold resistance index to cyhalofop-butyl. Molecular analyses revealed that this resistance was attributed to a tryptophan (Trp)-2027-to-cysteine (Cys) substitution in the CT domain of the ACCase gene. To our knowledge, this is the first report revealing the mechanism underlying cyhalofop-butyl resistance in L. chinensis. Furthermore, a derived cleaved amplified polymorphic (dCAPS) assay was developed to rapidly detect the Trp-2027-Cys mutation. Of the 100 ZHYH plants analyzed, 52 were heterozygous mutants and 48 were susceptible homozygous plants. In addition, the cyhalofop-butyl-resistant L. chinensis was cross-resistant to aryloxyphenoxypropionate and phenylpyrazoline herbicides, but not to cyclohexanedione, acetolactate synthase-inhibiting, protoporphyrinogen oxidase, and urea herbicides, and had only slight resistance to the hormonal herbicide quinclorac.
中国看麦娘（Leptochloa chinensis (L.) Nees）是稻田中一种严重的杂草。在过去五年中，由于频繁且广泛地使用草甘膦丁酯除草剂，一些地区的中国看麦娘已经对该除草剂产生了抗性。本研究进行了全株剂量反应试验，发现一个中国看麦娘种群（ZHYH）对草甘膦丁酯的抗性指数达到了 75.8 倍。分子分析表明，这种抗性归因于 ACCase 基因 CT 结构域中色氨酸（Trp）2027 突变为半胱氨酸（Cys）。据我们所知，这是首次报道揭示中国看麦娘对草甘膦丁酯产生抗性的机制。此外，还开发了一种衍生的切割扩增多态性（dCAPS）检测方法，用于快速检测 Trp-2027-Cys 突变。在分析的 100 株 ZHYH 植物中，有 52 株为杂合突变体，48 株为敏感纯合植株。此外，抗草甘膦丁酯的中国看麦娘对芳氧苯氧丙酸类和苯氧嘧啶类除草剂具有交叉抗性，但对环己二酮、乙酰乳酸合成酶抑制剂、原卟啉原氧化酶和尿素类除草剂没有抗性，对激素除草剂氯喹啉酸仅有轻微抗性。
