Mesotrione: a new selective herbicide for use in maize.
Mesotrione is a new herbicide being developed for the selective pre- and post-emergence control of a wide range of broad-leaved and grass weeds in maize (Zea mays). It is a member of the benzoylcyclohexane-1,3-dione family of herbicides, which are chemically derived from a natural phytotoxin obtained from the Californian bottlebrush plant, Callistemon citrinus. The compound acts by competitive inhibition of the enzyme 4-hydroxyphenylpyruvate dioxygenase (HPPD), a component of the biochemical pathway that converts tyrosine to plastoquinone and alpha-tocopherol. Mesotrione is an extremely potent inhibitor of HPPD from Arabidopsis thaliana, with a Ki value of c 6-18 pM. It is rapidly taken up by weed species following foliar application, and is distributed within the plants by both acropetal and basipetal movement. Maize is tolerant to mesotrione as a consequence of selective metabolism by the crop plant. Slower uptake of mesotrione, relative to susceptible weed species, may also contribute to its utility as a selective herbicide for use in maize.
Mitchell
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G
Zeneca Agrochemicals, Jealott's Hill International Research Centre, Bracknell, Berkshire RG42 6ET, UK. glynn.g.mitchell@aguk.zeneca.com
Bartlett
D W
DW
Fraser
T E
TE
Hawkes
T R
TR
Holt
D C
DC
Townson
J K
JK
Wichert
R A
RA
D015111:4-Hydroxyphenylpyruvate Dioxygenase / Q000037:antagonists & inhibitors*; D003512:Cyclohexanones / Q000138:chemical synthesis / Q000737:chemistry / Q000378:metabolism / Q000494:pharmacology*; D004791:Enzyme Inhibitors / Q000138:chemical synthesis / Q000378:metabolism / Q000494:pharmacology*; D006540:Herbicides / Q000138:chemical synthesis / Q000737:chemistry / Q000378:metabolism / Q000494:pharmacology*; D015394:Molecular Structure; D018515:Plant Leaves / Q000378:metabolism; D010944:Plants / Q000187:drug effects* / Q000378:metabolism; D013329:Structure-Activity Relationship; D003313:Zea mays / Q000378:metabolism*
D003512:Cyclohexanones; D004791:Enzyme Inhibitors; D006540:Herbicides; C432907:mesotrione; D015111:4-Hydroxyphenylpyruvate Dioxygenase