EPSPS duplication and mutation involved in glyphosate resistance in the allotetraploid weed species Poa annua L.
EPSPS duplication and mutation involved in glyphosate resistance in the allotetraploid weed species Poa annua L.
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DOI：
10.1002/ps.5284
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发表时间：
2019-06-01
影响因子：
4.1
通讯作者：
Hanson, Bradley D.
中科院分区：
文献类型：
--
作者：
Brunharo, Caio Augusto De Castro Grossi;Morran, Sarah;Hanson, Bradley D.
背景：黄花草是一种在加州广泛分布的冬季一年生杂草。最近，加州一个杏仁果园的种植者报告了草甘膦对该物种的不良控制，该果园有重复使用草甘膦的历史。本研究的目的是评估已开发的S-4稻瘟病系(R)对草甘膦的抗性水平，并确定其抗性机制。结果：全株剂量反应实验证实了R对草甘膦的抗性，与敏感品系(S)相比，R需要比S多18倍的草甘膦才能实现50%的生长减少，这一结果得到了R比S更低的草甘膦积累的支持。没有观察到草甘膦吸收、易位或代谢的差异，表明抗性的非靶点机制不参与抗性表型。在R中EPSPS编码位置106处存在错义单核苷酸多态性，导致亮氨酸被脯氨酸取代。这种多态性仅在棘鱼EPSPS同源物中观察到。结论我们报道了首例与EPSPS重复和106位靶位点突变相关的草甘膦抗性病例，这导致了异源四倍体杂草Poa annua l的高水平草甘膦抗性。本研究获得的数据将有助于开发诊断工具，用于快速鉴定、监测和遏制草甘膦抗性。(c) 2018年化学工业学会
BACKGROUND Poa annua is a widespread winter annual weed species in California. Recently, poor control of this species with glyphosate was reported by growers in an almond orchard in California with a history of repetitive glyphosate use. The objectives of this research were to evaluate the level of glyphosate resistance in a developed S-4 P. annua line (R) and identify the mechanisms of resistance involved. RESULTS Whole-plant dose-response experiments confirmed glyphosate resistance in R, which required 18-fold more glyphosate to achieve a 50% growth reduction compared with a susceptible line (S), results that were supported by the lower shikimate accumulation observed in R compared with S. No differences in glyphosate absorption, translocation, or metabolism were observed, suggesting that non-target-site mechanisms of resistance are not involved in the resistance phenotype. A missense single nucleotide polymorphism was observed in EPSPS coding position 106 in R, resulting in a leucine to proline substitution. This polymorphism was observed exclusively in P. supina EPSPS homeologs. A seven-fold increase in the number of copies of EPSPS alleles was observed in R compared with S. CONCLUSIONS We report the first case of glyphosate resistance associated with both EPSPS duplication and target-site mutation at position 106, leading to high levels of glyphosate resistance in the allotetraploid weed species Poa annua L. Data obtained in this research will be useful for the development of diagnostic tools for rapid glyphosate resistance identification, monitoring and containment. (c) 2018 Society of Chemical Industry