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Published on: September 7, 2015
Rapid vacuolar sequestration: the horseweed glyphosate resistance mechanism
Xia Ge1, D André d'Avignon, Joseph J H Ackerman
1Department of Chemistry, Washington University, St Louis, MO 63130, USA.
Background:
Glyphosate-resistant (GR) weed species are now found with increasing frequency and threaten the critically important glyphosate weed-management system [corrected].
Results:
The reported (31)P NMR experiments on glyphosate-sensitive (S) and glyphosate-resistant (R) horseweed, Conyza canadensis (L.) Cronq., show significantly more accumulation of glyphosate within the R biotype vacuole.
Conclusions:
Selective sequestration of glyphosate into the vacuole confers the observed horseweed resistance to glyphosate. This observation represents the first clear evidence for the glyphosate resistance mechanism in C. canadensis.
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