Choline-based ionic liquids as adjuvants in pesticide formulation

Abstract Current research focusing on using compounds of natural origin has led to the synthesis of new biobased ionic liquids (ILs) with surface-activity containing a dodecyl(2-hydroxyethyl)dimethylammonium cation and anions of natural ( d -gluconate, α-ketoglutarate, l -pyroglutamate, cholate or glycolate) or synthetic origin (dioctyl sulfosuccinate or bis(2-ethylhexyl)phosphate). The influence of the anion on the physicochemical properties (thermal stability, phase transitions, solubility, surface-activity, refractive index) was examined. Subsequently, the obtained ILs' impacts as herbicide additives were assessed on a common windgrass (Apera spica-venti L. Beauv) using the greenhouse test, and the toxicity of the compounds toward bacteria, fungi, and plants was evaluated. We established that the surface wettability of tank mixes and their biological activity were correlated. This discovery may greatly facilitate the design of new, biocompatible adjuvants of low toxicity, which can be particularly useful as additives to plant protection products in organic farming.