Key Laboratory of Weed and Rodent Biology and Management, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing 100193, PR China.
Key Laboratory of Weed and Rodent Biology and Management, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing 100193, PR China.
Pestic Biochem Physiol. 2017 Nov;143:201-206. doi: 10.1016/j.pestbp.2017.09.012. Epub 2017 Sep 23.
The evolution of weed-resistant species threatens the sustainable use of glyphosate, which is the most important herbicide widely used in agriculture worldwide. Moreover, the high glyphosate resistance (>180-fold based on LD) of Eleusine indica found in Malaysia, which carries a double mutation in its 5-enolpyruvylshikimate-3-phosphate synthase (EPSPS), made the control of this species more difficult. By contrast, the same species carrying the same double mutation in EPSPS (T102I+P106S) but found in China only shows a resistance level of not more than 14-fold based on GR. The resistance level of this population is four times higher than that of the population carrying a single mutation (P106L). Although the members of this population survive under a high glyphosate dosage of 10,080gaeha, their growth was significantly inhibited by glyphosate under the recommend dose (840gaeha), where in the fresh weight was 85.4% of the control. EPSPS expression, relative copy number, and EPSPS activity in this population were similar to those of the susceptible population. In addition, the expression of two glutathione transferase (GST) genes (GST-U8 and GST-23) and the enzyme activity of the GST in this population did not significantly differ from those of the susceptible population. This finding is important in elucidating the resistance of the naturally evolved glyphosate-resistant (GR) weed species carrying a double mutation in EPSPS to glyphosate.
杂草抗药性的进化威胁到草甘膦的可持续使用，草甘膦是全球农业中使用最广泛的最重要的除草剂。此外，在马来西亚发现的节节麦对草甘膦具有高抗药性（基于 LD 超过 180 倍），其 5-烯醇丙酮酰莽草酸-3-磷酸合酶（EPSPS）发生双重突变，这使得对该物种的控制更加困难。相比之下，在同样携带 EPSPS 中相同双重突变（T102I+P106S）的同一物种（但在中国发现），仅根据 GR 显示的抗药性水平不超过 14 倍。该种群的抗药性水平比携带单个突变（P106L）的种群高四倍。尽管该种群的成员在 10080gaeha 的高草甘膦剂量下存活，但在推荐剂量（840gaeha）下，草甘膦明显抑制了它们的生长，其鲜重仅为对照的 85.4%。该种群的 EPSPS 表达、相对拷贝数和 EPSPS 活性与敏感种群相似。此外，该种群中两个谷胱甘肽转移酶（GST）基因（GST-U8 和 GST-23）的表达和 GST 酶活性与敏感种群没有显著差异。这一发现对于阐明携带 EPSPS 双重突变的自然进化的草甘膦抗性（GR）杂草物种对草甘膦的抗性具有重要意义。
