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Utility Adjuvants

Published online by Cambridge University Press:  20 January 2017

Patrick M. McMullan*
Affiliation:
Agrobiology Research, Inc., 7777 Walnut Grove Road, Box 57, Memphis, TN 38120

Abstract

Utility adjuvants are adjuvants that are tank-mixed in the spray solution to improve the spray application process, but do not directly influence herbicide efficacy. However, by improving the spray application process, utility adjuvants can indirectly improve herbicide efficacy. There are five primary utility adjuvant types: compatibility agents, deposition agents, drift control agents (sometimes referred to as antidrift agents or drift retardants), defoaming agents, and water conditioning agents, and three secondary utility adjuvant types: acidifying agents, buffering agents, and colorants (dye markers). Herbicides can react either physically or chemically with other spray mixture components to form an unsprayable mixture. Compatibility agents prevent these reactions from occurring. Drift control agents and deposition agents increase the amount of herbicide deposited on target surfaces. The primary function of drift control agents is to reduce the amount of spray solution that moves off-target. Indirectly, the amount of herbicide reaching target surfaces can be increased. A defoaming agent will reduce or prevent foam produced in the spray mixture. Ions in the spray solution can interact with various herbicides, decreasing efficacy. Water conditioning agents will counteract the effect of the ions on herbicides. Water conditioning agents must be added before the herbicide to prevent herbicide–ion interaction. Acidifying and buffering agents function in a similar fashion, reducing or increasing spray solution pH. A buffering agent will maintain a pH range, whereas an acidifying agent will not. Colorants are dyes that are added to the spray solution to produce a visible color on the sprayed area to assist the applicator in applying the herbicide.

Type
Symposium
Copyright
Copyright © Weed Science Society of America 

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References

Literature Cited

ASTM. 1995. Terminology relating to agricultural tank mix adjuvants. In Annual Book of ASTM Standards. Volume 11.05: Biological Effects and Environmental Fate; Biotechnology; Pesticides. Philadelphia, PA. pp. 966967.Google Scholar
Buhler, D. D. and Burnside, O. C. 1983. Effect of water quality, carrier volume, and acid on glyphosate efficacy. Weed Sci. 31: 163169.CrossRefGoogle Scholar
Chamberlain, P. and Rose, S. A. 1998. Effect of non-ionic polyacrylamides on spray droplet size, spray drift, and pesticide efficacy. In McMullan, P. M., ed. Adjuvants for Agrochemicals. Challenges and Opportunities. Proc. Fifth Int. Symp. on Adjuvants for Agrochemicals. Volume I. Memphis, TN. pp. 463467.Google Scholar
Downer, R. A., Mack, R. E., Hall, F. R., and Underwood, A. K. 1998. Roundup Ultra with drift management adjuvants: Some aspects of performance. In McMullan, P. M., ed. Adjuvants for Agrochemicals. Challenges and Opportunities. Proc. Fifth Int. Symp. on Adjuvants for Agrochemicals. Volume I. Memphis, TN. pp. 468474.Google Scholar
Downer, R. A., Wolf, T. M., Chapple, A. C., Hall, F. R., and Hazen, J. L. 1995. Characterizing the impact of drift management adjuvants on the dose transfer process. In Gaskin, R. E., ed. Proc. Fourth Int. Symp. on Adjuvants for Agrochemicals. Rotorua, New Zealand. pp. 138143.Google Scholar
Farris, M. E. 1991. The effect of Penetrator and Penetrator Plus on pesticide deposition, evaporation, and foliage residue in cotton. Proceedings of the Beltwide Cotton Conference, Volume 2. pp. 768771.Google Scholar
Hall, F. R., Downer, R. A., and Bagley, W. E. 1998a. Laboratory and greenhouse studies with an invert suspension. In McMullan, P. M., ed. Adjuvants for Agrochemicals. Challenges and Opportunities. Proc. Fifth Int. Symp. on Adjuvants for Agrochemicals. Volume I. Memphis, TN. pp. 407412.Google Scholar
Hall, F. R., Downer, R. A., and Latting, J. A. 1998b. Improving herbicide efficacy with adjuvant/ammonium sulfate combinations. In McMullan, P. M., ed. Adjuvants for Agrochemicals. Challenges and Opportunities. Proc. Fifth Int. Symp. on Adjuvants for Agrochemicals. Volume I. Memphis, TN. pp. 475480.Google Scholar
Hazen, J. L. and Olsen, R. L. 1995. Agrhô DR-2000 drift reduction adjuvant—atomization performance evaluation under good laboratory practice (GLP) protocols. In Gaskin, R. E., ed. Proc. Fourth Int. Symp. on Adjuvants for Agrochemicals. Rotorua, New Zealand. pp. 126131.Google Scholar
Hewitt, A. J. 1998. The effect of tank mix and adjuvants on spray drift. In McMullan, P. M., ed. Adjuvants for Agrochemicals. Challenges and Opportunities. Proc. Fifth Int. Symp. on Adjuvants for Agrochemicals. Volume I. Memphis, TN. pp. 451462.Google Scholar
Huddleston, E. W., Hewitt, A. J., Ledson, T. M., Sanderson, R., Ross, J. B., and Steiner, R. L. 1995. Polymer formulation and concentration effects on droplet spectra in simulated aerial sprays. In Gaskin, R. E., ed. Proc. Fourth Int. Symp. on Adjuvants for Agrochemicals. Rotorua, New Zealand. pp. 132137.Google Scholar
McMullan, P. M. 1994. Effect of sodium bicarbonate on clethodim or quizalofop efficacy and the role of ultraviolet light. Weed Technol. 8: 572575.CrossRefGoogle Scholar
Matysiak, R. and Nalewaja, J. D. 1999. Temperature, adjuvants, and UV light affect sethoxydim phytotoxicity. Weed Technol. 13: 9499.CrossRefGoogle Scholar
Nalewaja, J. D., Manthey, F. A., Szelezniak, E. F., and Anyska, J. 1989. Sodium bicarbonate antagonism of sethoxydim. Weed Technol. 3: 654658.CrossRefGoogle Scholar
Nalewaja, J. D. and Matysiak, R. 1993. Influence of diammonium sulfate and other salts on glyphosate phytotoxicity. Pestic. Sci. 38: 7784.CrossRefGoogle Scholar
Reichard, D. L., Zhu, H., Downer, R. A., Fox, R. D., Brazee, R. D., Ozkan, H. E., and Hall, F. R. 1996. A system to evaluate shear effects on spray drift retardant performance. Trans. Am. Soc. Agric. Eng. 39: 19931999.CrossRefGoogle Scholar
Richards, M. D., Holloway, P. J., and Stock, D., 1998. Structure-spray retention enhancement relationships for some polymers and polymeric surfactants. In McMullan, P. M., ed. Adjuvants for Agrochemicals. Challenges and Opportunities. Proc. Fifth Int. Symp. on Adjuvants for Agrochemicals. Volume I. Memphis, TN. pp. 7984.Google Scholar
Roberts, J. R., Underwood, A. K., Clark, A., Mack, R. E., Thomas, J. M., and Volgas, G. C. 1997. Dry concentrate (DC) spray adjuvants. In Goss, G. R., Hopkinson, M. J., and Collins, H. M., eds. Pesticide Formulations and Application Systems: 17th Volume, ASTM STP 1328. West Conshohocken, PA: American Society for Testing and Materials. pp. 257266.CrossRefGoogle Scholar
Thelen, K. D., Jackson, E. P., and Penner, D. 1995. Utility of nuclear magnetic resonance for determining the molecular influence of citric acid and an organosilicone adjuvant on glyphosate activity. Weed Sci. 43: 566571.CrossRefGoogle Scholar