References

Anderson, M. and Gronwald, J. (1991) Atrazine resistance in a velvetleaf (Abutilion theophrasti) biotype due to enhanced glutathione S-transferase activity. Plant Physiology 96, 104-109. Barnwell, P. and Cobb, A.H. (1989) Physiological studies of mecoprop-resistance in chickweed (Stellaria media L.). WeedResearch 29, 135-140. Bernasconi, P., Woodworth, A.R., Rosen, B.A., Subramanian, M.V. and Siehl, D.L. (1995) A naturally occurring point mutation confers broad range tolerance to herbicides...

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...

How treated plants die

It is not clearly understood how treated plants die following ALS inhibition. The diminution of the branched-chain amino acid pool will contribute to a cessation of protein synthesis, but although nanomolar concentrations of herbicide can inhibit ALS within minutes in vitro, it may take up to two months for the death of intact weeds in the field. Addition of the three branched-chain amino acids to culture media alleviates symptoms of ALS-)nhibiting herbicides (Ray, 1984 Shaner and Reider, 1986...

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...