Herbicide safeners and synergists

Herbicide safeners, also termed antidotes in some texts, are chemicals that, when applied before or with herbicides, increase the tolerance of a cereal crop to a herbicide. This activity has been known since the 1970s and the safening effect is not seen on the weeds. A list of herbicide safeners available as commercial products is given in Table 4.2. As some safeners may show structural homology with herbicides, it was previously thought that they competed with the herbicide molecule for the...

Phases of herbicide metabolism

Herbicide metabolism has been well documented in the last two decades and much progress has been made in our understanding of the enzyme systems involved and where they act in the plant cell. The four phases commonly observed are as follows Some herbicides have been shown to undergo bioactivation within plant cells, where a pro-herbicide is converted to a phytotoxic agent by the action of plant enzymes. Before this activation they may be less or non-phytotoxic, so the plant can be instrumental...