Institute of Sugar Beet Research, Department of Phytopathology, Göttingen, Germany.
Pest Manag Sci. 2010 Sep;66(9):1011-7. doi: 10.1002/ps.1975.
Resistance to photosystem II inhibitors-triazines (atrazine) and triazinones (metamitron, metribuzin)-in Chenopodium album L. is caused by the serine 264 to glycine mutation in the D1 protein. This mutation has been detected in C. album collections from Belgium with unsatisfactory metamitron efficacy in the field and was confirmed in greenhouse resistance bioassays. Incomplete herbicide efficacy in practice can also be caused by reduced uptake due to environmental conditions. Hence, for reliable differentiation and resistance identification, a rapid method for mutation detection in the target gene psbA is required.
Dose-response curves obtained in herbicide greenhouse assays with metamitron-resistant and -susceptible reference biotypes showed that a dose of 2 L ha(-1) metamitron was suitable for discrimination. A psbA PCR-RFLP was developed, based on the presence of a FspBI restriction enzyme recognition site, covering D1 codon 264 in susceptible genotypes. A paper-based DNA extraction allowed direct processing of leaf samples already in the field. In order to detect the mutation even in mixed seed samples, a nested PCR-RFLP was also developed.
The method allows exhaustive surveys screening C. album leaf or seed samples for the occurrence of the D1 Ser264Gly mutation to confirm or disprove metamitron resistance in the case of unsatisfactory control.
苯并噻二嗪类（莠去津）和三嗪酮类（甲胂威、扑灭通）类除草剂对鸭跖草的抗药性是由 D1 蛋白中丝氨酸 264 突变为甘氨酸引起的。该突变已在比利时的鸭跖草种群中被检测到，田间甲胂威效果不理想，并在温室抗性生物测定中得到证实。由于环境条件导致吸收减少，实际中除草剂效果不完全也可能是由吸收减少引起的。因此，需要一种快速的方法来检测靶基因 psbA 中的突变，以进行可靠的区分和抗性鉴定。
用甲胂威抗性和敏感参考生物型进行温室除草剂测定得到的剂量-反应曲线表明，2 L ha(-1)的甲胂威剂量适合用于区分。基于 FspBI 限制性内切酶识别位点的存在，开发了一种 psbA PCR-RFLP，可覆盖敏感基因型中 D1 密码子 264。基于纸张的 DNA 提取允许直接处理现场的叶片样本。为了即使在混合种子样本中也能检测到突变，还开发了一种嵌套 PCR-RFLP。
该方法允许对鸭跖草叶片或种子样本进行全面调查，以筛选 D1 Ser264Gly 突变的发生情况，从而在控制效果不理想的情况下证实或否定甲胂威的抗性。
