Halauxifen-methyl is a new auxin herbicide developed by Corteva Agriscience (Wilmington, DE, USA). It has been suggested that ABF5 may be the target of halauxifen-methyl, as AFB5 mutants of Arabidopsis thaliana are resistant to halauxifen-methyl, which preferentially binds to AFB5. However, the mode of action of halauxifen-methyl has not yet been reported. Therefore, the aim of the present study was to reveal the mode of action of halauxifen-methyl by exploring its influence on indole-3-acetic acid (IAA) homeostasis and the biosynthesis of ethylene and Abscisic Acid (ABA) in Galium aparine. The results showed that halauxifen-methyl could disrupt the homeostasis of IAA and stimulate the overproduction of ethylene and ABA by inducing the overexpression of the 1-aminocyclopropane-1-carboxylate synthase (ACS) and 9-cis-epoxycarotenoid dioxygenase (NCED) genes involved in ethylene and ABA biosynthesis, finally leading to senescence and plant death.

中文翻译：

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新型合成生长素除草剂 Halauxifen-Methyl 的作用方式

Halauxifen-methyl 是 Corteva Agriscience (Wilmington, DE, USA) 开发的一种新型生长素除草剂。有人提出ABF5可能是 halauxifen-methyl 的靶标，因为拟南芥的AFB5突变体对halauxifen-methyl 具有抗性，后者优先与AFB5结合。然而，尚未报道甲基卤代芬的作用方式。因此，本研究的目的是通过探索其对吲哚-3-乙酸 (IAA) 稳态和乙烯和脱落酸 (ABA) 生物合成的影响来揭示卤代芬的作用方式。. 结果表明，halauxifen-methyl 可通过诱导 1-氨基环丙烷-1-羧酸合酶 ( ACS ) 和 9-cis-环氧类胡萝卜素双加氧酶 ( NCED ) 基因的过度表达来破坏 IAA 的稳态并刺激乙烯和 ABA 的过量产生。在乙烯和 ABA 的生物合成中，最终导致植物衰老和死亡。