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The Basis of Bentazon Antagonism on Sethoxydim Absorption and Activity

  • Gunawan Wanamarta (a1), Donald Penner (a1) and James J. Kells (a1)


The antagonistic effect of bentazon on sethoxydim adsorption and activity was studied in quackgrass. The diffusion of 14C-sethoxydim into and through an isolated tomato fruit cuticle was inhibited in the presence of the sodium salt of bentazon. Bentazon also increased the partitioning of 14C-sethoxydim into CH2Cl2 and water; however, it decreased partitioning into ethyl acetate. Removal of epicuticular wax from quackgrass leaf surfaces did not prevent the antagonism. Addition of sodium acetate or sodium bicarbonate to the sethoxydim spray solution at 10 mM reduced uptake of 14C-sethoxydim by quackgrass similar to the effect of bentazon. Sodium ions in the bentazon formulation appeared responsible for the antagonism by exchanging with the H+ of the sethoxydim hydroxyl group to form a more polar sodium salt of sethoxydim. The addition of Li+, K+, Cs+, Ca++, and Mg++ cations associated with a weak acid also reduced 14C-sethoxydim absorption. Addition of organic acids to the spray solution overcame the antagonism by preventing the formation of sodium salt of sethoxydim. In the field, the addition of a 3000 ppm sodium acetate solution delivering 0.56 kg/ha produced the same antagonism as bentazon on quackgrass control with sethoxydim.



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1. Bayer, D. E. and Lumb, J. M. 1973. Penetration and translocation of herbicides. Pages 387439 in van Valkenburg, W., ed. Pesticide Formulations. Marcel-Dekker, New York.
2. Buhler, D. D. and Burnside, O. C. 1983. Effect of water quality, carrier volume, and acid on glyphosate phytotoxicity. Weed Sci. 31:163169.
3. Bukovac, M. J., Sargent, J. A., Powell, R. G., and Blackman, G. E. 1971. Studies on foliar penetration. VIII. Effects of chlorination on the movements of phenoxyacetic and benzoic acids through cuticles isolated from the fruits of Lycopersicon esculentum L. J. Exp. Bot. 22:598612.
4. Campbell, J. R. and Penner, D. 1982. Compatibility of diclofop and BAS 9052 with bentazon. Weed Sci. 30:458462.
5. Hartzler, R. G. and Foy, C. L. 1983. Compatibility of BAS 9052 OH with acifluorfen and bentazon. Weed Sci. 31:597599.
6. Orgell, W. H. 1955. Isolation of plant cuticle with pectic enzymes. Plant Physiol. 30:7880.
7. Putnam, A. R. and Penner, D. 1974. Pesticide interactions in higher plants. Residue Rev. 50:73110.
8. Rhodes, G. N. Jr. and Coble, H. D. 1984. Influence of application variables on antagonism between sethoxydim and bentazon. Weed Sci. 32:436441.
9. Rhodes, G. N. Jr. and Coble, H. D. 1984. Influence of bentazon on absorption and translocation of sethoxydim in goosegrass (Eleusine indica L.). Weed Sci. 32:595597.
10. Robertson, M. M. and Kirkwood, R. C. 1969. The mode of action of foliage applied translocated herbicides with particular reference to the phenoxy acid compounds. Weed Res. 9:224240.
11. Sandberg, C. L., Meggitt, W. F., and Penner, D. 1978. Effect of diluent volume and calcium on glyphosate phytotoxicity. Weed Sci. 26:476479.
12. Stahlman, P. W. and Phillips, W. M. 1979. Effects of water quality and spray volume on glyphosate phytotoxicity. Weed Sci. 27:3841.
13. Turner, D. J. and Loader, M.P.C. 1978. Complexing agents as herbicide additives. Weed Res. 18:199207.
14. Wanamarta, G., Penner, D., and Kells, J. J. 1989. Identification of efficacious adjuvants for sethoxydim and bentazon. Weed Technol. 3:6066.


The Basis of Bentazon Antagonism on Sethoxydim Absorption and Activity

  • Gunawan Wanamarta (a1), Donald Penner (a1) and James J. Kells (a1)


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