Glycine betaine-based ionic liquids and their influence on bacteria, fungi, insects and plants†

A new group of bioinspired ionic liquids (ILs) based on glycine betaine and natural or synthetic anions was synthesized. The developed synthesis methods enabled the preparation of designed salts with high yields. The melting points for 17 of the 21 betaine-based salts were below 100 degrees C, allowing them to be classified as ionic liquids. Moreover, the solubilities of the novel salts in water and organic solvents of different polarities were examined, and their surface activity was determined. In the greenhouse experiment, all ILs were used as pesticide adjuvants, and their impact on the herbicidal activity of iodosulfuron-methyl was determined. Additionally, the effects of the obtained salts on the deterrent properties towards pests as well as on toxicity to microorganisms and plants were determined. It turned out that most of the ILs were weak feeding deterrents; however, their toxicity to the examined organisms was relatively low. The conclusion is that some of the presented salts are high-quality pesticide adjuvants that are safe for the environment and exhibit potential weak activity towards storage pests. An essential aspect of this work was also the correlation of herbicidal activity with the wettability of hydrophobic surfaces.