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Mechanism of action and selectivity of a novel herbicide, fenquinotrione.

ABSTRACT: Fenquinotrione is a novel herbicide that can control a wide range of broadleaf and sedge weeds with excellent rice selectivity. We revealed that fenquinotrione potently inhibited the 4-hydroxyphenylpyruvate dioxygenase (HPPD) activity in Arabidopsis thaliana with an IC₅₀ of 44.7 nM. The docking study suggested that the 1,3-diketone moiety of fenquinotrione formed a bidentate interaction with Fe(II) at the active site. Furthermore, π-π stacking interactions occurred between the oxoquinoxaline ring and the conserved Phe409 and Phe452 rings, indicating that fenquinotrione competes with the substrate, similar to existing HPPD inhibitors. A more than 16-fold difference in the herbicidal activity of fenquinotrione in rice and the sedge, Schoenoplectus juncoides, was observed. However, fenquinotrione showed high inhibitory activity against rice HPPD. Comparative metabolism study suggested that the potent demethylating metabolism followed by glucose conjugation in rice was responsible for the selectivity of fenquinotrione.

SUBMITTER: Yamamoto S

PROVIDER: S-EPMC8422254 | biostudies-literature | 2021 Aug

REPOSITORIES: biostudies-literature

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Mechanism of action and selectivity of a novel herbicide, fenquinotrione.

Yamamoto Shunsuke S Tanetani Yoshitaka Y Uchiyama Chihiro C Nagamatsu Atsushi A Kobayashi Masami M Ikeda Mitsumasa M Kawai Kiyoshi K

Journal of pesticide science 20210801 3

Fenquinotrione is a novel herbicide that can control a wide range of broadleaf and sedge weeds with excellent rice selectivity. We revealed that fenquinotrione potently inhibited the 4-hydroxyphenylpyruvate dioxygenase (HPPD) activity in <i>Arabidopsis thaliana</i> with an IC<sub>50</sub> of 44.7 nM. The docking study suggested that the 1,3-diketone moiety of fenquinotrione formed a bidentate interaction with Fe(II) at the active site. Furthermore, π-π stacking interactions occurred between the ...[more]

PMID: 34566458

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Mechanism of action and selectivity of a novel herbicide, fenquinotrione.

Publications

Mechanism of action and selectivity of a novel herbicide, fenquinotrione.

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