|Book Title:||PESTICIDE FORMULATIONS AND APPLICATION SYSTEMS: 23RD VOLUME|
|Author:||de Ruiter, H|
|Book Group Author:||NA|
The herbicide 2,4-D is an important herbicide at a global level. In 1999, the herbicide was ranked as the fifth herbicide in the United States regarding sales. The 2,4-D amine salts are generally not applied in combination with adjuvants. An effective and inexpensive adjuvant, either as built-in or as tank-mix adjuvant, can create a new product with benefits for the user and the environment. Such a product can be an alternative for the 2,4-D esters requiring emulsion-type formulations. The objective of this study is to investigate whether a review of published data, insight in the adjuvant-action and knowledge of the weed species may result in a list of adjuvant types being effective for 2,4-D amine salts. The lipophilicity of the 2,4-D molecule depends on the pH-dependent dissociation of the carboxylic group. Both hydrophilic and lipophilic adjuvants can be effective for 2,4-D amine salts. It will be discussed in how far this is related to the pH-dependent ionic character of 2,4-D. Ion-pair formation by association of the 2,4-D anion with a cationic counter ion as a tool for improving herbicide performance will be discussed. Calcium ions in the water used as carrier may reduce the performance of 2,4-D. It will be discussed in how far adjuvants may overcome this antagonistic effect of calcium.
|Organization:||Amer Soc Testing & Mat, E35 22 Subcomm|
|Publisher:||AMERICAN SOCIETY TESTING AND MATERIALS|
2,4-D; 2,4-dichlorophenoxy acetic acid; 2,4-D amine; adjuvant; surfactant; pH; ion-pair
|Source:||Web of Science|