Herbicide selectivity glutathione conjugation

Shimabukuro, R.H., G.L. Lamoureux, and D.S. Frear. (1978). Glutathione conjugation A mechanism for herbicide detoxification and selectivity in plants, pp. 133-149. In Pallos, F.M. and J.E. Casida, eds., Chemistry and Action of Herbicide Antidotes. New York Academic Press Inc. 

Propachlor Is metabolized by this route In both a resistant and a susceptible species (Equation 16). Glutathione conjugation of propachlor occurs very rapidly Un vitro in the absence of GST enzymes (78) and It Is not clear whether differences In GSH and/or GST concentratlois influence the selectivity of propachlor and related herbicides. The concentration of GSH In higher plants Is estimated... 

Figure 9.5 The metabohsm of glutathione and homoglutathione conjugates in higher plants. [Reproduced from G. L. Lamoreux, R. H. Shimabukuro, and D. S. Frear Glutathione and Glucoside Conjugation in Herbicide Selectivity , in J. C. Caseley, G. W. Cussans, and R. K. Atkin, Eds., Herbicide Resistance in Weeds and Crops, Butterworth-Heinemann Ltd., Oxford, pp. 227-262. Copyright 1991, with permission from Elsevier.]...

The same biotypes, Peldon A1 and Lines. El, are also resistant to the gramini-cide fenoxaprop, which is used for selective control of A. myosuroides and other grass weeds in cereals, mainly wheat. On a whole plant level. Lines. El was more resistant than Peldon Al. The selectivity of this herbicide has been attributed to rapid detoxification by GST-catalyzed conjugation in the cereal species. In both resistant A. myosuroides biotypes GST activities towards fenoxaprop were found to be increased to a similar degree, when compared with a susceptible biotype. This was due to increased expression of a constitutive GST and to expression of two novel GST isoenzymes. Furthermore, glutathione levels were increased in the resistant biotypes, in Peldon more than in Lines. The data pointed to an involve-... 

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