Agrochemical adjuvants

Agrochemical adjuvants are widely used to improve agrochemical applications. Improvement can be interpreted as better weed/disease control or reducing active ingredient per hectare , or even reducing amount of water to spray per hectare . Claims related to the adjuvant function vary from wetter , spreader , sticker , penetrator to synergist . 

Surfactants are often used in agrochemical formulations as adjuvants, e.g. as wetting agents to improve the physico-chemical characteristics of the solution and to increase the uptake of active ingredients (e.g. pesticides) [6-8]. The surfactants can be included in pesticide products and/or added to the tank mix prior to use however, they rarely exceed 1% of the total applied spray. Examples of typical surfactants used in agrochemical formulations are shown in Table 2.8.3 [9]. 

The total world consumption of surfactants as agricultural adjuvants was estimated to be 60,000 t in 1993 [10], and this figure is expected to continue to increase as more concerted efforts are made to reduce the amounts of crop protection chemicals used. Indeed, whilst figures in 1995 showed the worldwide adjuvant market valued at only 3% that of the corresponding agrochemicals, the increase in use per annum was 5% as compared with 1.5% per annum for the agrochemicals [9]. 

J.A. Zabkiewicz, W.A. Forster, L.S. Bonnington and W. Henderson, Proc. 6th International Symposium on Adjuvants for Agrochemicals, Amsterdam, August 13—17, 2001. 

Sun JS, Foy CL (1996) Structurally related organosilicone surfactants, their physicochemical properties and effects on uptake and efficacy of primisulfuron in velvetleaf (Abutilon theophrasti Medicus). FRI Bulletin 193 225-230 (Proceedings of the fourth international symposium on adjuvants for agrochemicals, 1995)... 

Rogiers, L.M. (1995). Adjuvants and efficacy, in New Trends in the Formulation of Adjuvants, Proceedings of the 4th International Symposium on Adjuvants for Agrochemicals, 3-6 October, 1995, Melbourne, Australia, Forest Research Institute Bulletin, No. 193, R.E. Gastein (Ed.), New Zealand Forest Research Institute, Toturua, New Zealand,... 

Anderson NH and Hall DJ The role of dynamic surface tension in the retention of surfactant on pea plants, Adjuvants and Agrochemicals, Volume 2 Recent Development, Application, and Bibliography of Agroadjuvants, pp. 51-62, Chow, P.N.P., Grant, C., Hinshalwood, A.M. and Simundsson, E. (eds) (1989). 

Kudsk P The effect of adjuvants on the rainfastness of thifensulfuron and tribenuron, In Adjuvants for Agrochemicals, Foy CL (ed.), Wiley Interscience, UK (1992). 

Work has been carried out to determine the physical and chemical properties in relation to agrochemical formulations and especially their adjuvant effect on plant protection agents. Polyethoxy tallow amine was used as a model adjuvant for comparative purposes. The knowledge from extensive studies of physical and chemical properties shows that... 

Holloway, P.J. Improving agrochemical performance Possible mechanisms for adjuvancy, in D.A. Knowles (ed.). Chemistry and Technology of Agrochemical Formulations, Kluwer, Dordrecht, 1998, pp. 232-263. 

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