Agricultural spray adjuvant
Encyclopedia
In agriculture, an adjuvant is broadly defined as any substance added to the spray tank, (separate from the pesticide formulation) that will improve the performance of the pesticides, herbicides, feeding stimulants etc. The water molecule has a high surface tension and this leads to formation of water droplets when sprayed on a waxy surface. This results in pesticides not being able to spread evenly, leaving an irregular coverage resulting in higher use of pesticides. A spray drop must be able to wet the foliage and spread out or cover an area of the leaf for the pesticide to perform its pest control function. The adjuvant acts here by reducing the surface tension of the water on the surface of the spray drop and by reducing the interfacial tension between the spray drop and surface of the leaf. This requires an adjuvant that will preferentially aggregate at these surfaces. This may not be done effectively by the surfactants that form and stabilize the oil/water emulsion from the concentrate formulation.
The Pesticides Safety Directorate
(PSD) defines an adjuvant as a substance other than water which is not in itself a pesticide
but which enhances or is intended to enhance the effectiveness of the pesticide with which it is used. Adjuvants for use with agricultural pesticides have been categorised as extenders, wetting agents, sticking agents and fogging agents.
The American Society of Testing and Materials (ASTM) provides definitions for most commonly used agricultural spray adjuvant terms. These definitions can be found in their Standard E-1519, and are developed and maintained by ASTM subcommitee E35.
The Chemical Producers and Distributors Association offers participating companies the ability to self-certify their spray adjuvant products in the USA.
The Pesticides Safety Directorate
Pesticides Safety Directorate
The Pesticides Safety Directorate was an agency of the Department for Environment, Food and Rural Affairs . It was based in York with about 200 scientific, policy and support staff and was responsible for the authorisation of plant protection products and, from 2005, detergents, in the United...
(PSD) defines an adjuvant as a substance other than water which is not in itself a pesticide
Pesticide
Pesticides are substances or mixture of substances intended for preventing, destroying, repelling or mitigating any pest.A pesticide may be a chemical unicycle, biological agent , antimicrobial, disinfectant or device used against any pest...
but which enhances or is intended to enhance the effectiveness of the pesticide with which it is used. Adjuvants for use with agricultural pesticides have been categorised as extenders, wetting agents, sticking agents and fogging agents.
The American Society of Testing and Materials (ASTM) provides definitions for most commonly used agricultural spray adjuvant terms. These definitions can be found in their Standard E-1519, and are developed and maintained by ASTM subcommitee E35.
The Chemical Producers and Distributors Association offers participating companies the ability to self-certify their spray adjuvant products in the USA.