Olivia McClure, Blanchard, Tobie M., Gould, Frances I.
An LSU AgCenter researcher is getting closer to developing a better way to clean sprayers that are used to apply farm chemicals.
Zhijun Liu has spent the past two years working to formulate a plant-based solution that effectively removes pesticide residue. Sprayers must be thoroughly cleaned to get rid of leftover product, which can damage the equipment itself as well as subsequent crops being sprayed.
The cleaning process is difficult and time consuming, however. Many pesticides — especially those that are emulsifiable concentrate formulations, meaning they include solvents and surfactants — are not water soluble. Water alone will not completely wash away those products.
Commercially available cleaning products can help, but they still do not remove all the residue, Liu said.
In testing his plant-based cleanout solution, Liu has found that residues of 2,4-D herbicides vary considerably depending on which form of the ingredient the product contains.
2,4-D in the form of amine salt is water soluble, so its residue is easier to remove, Liu said. Acid formulated to a suspension concentrate is more difficult to clean, and acid ester formulated to an emulsifiable concentrate is even harder.
In each of those situations, Liu said, his cleanout solution removes leftover herbicide better than water.
Liu also has learned that cleaning results can vary by product brand.
“Formulating ingredients can be different due to proprietary nature,” Liu said. “For example, Sterling Blue by Winfield Solutions, Engenia by BASF and XtendiMax by Monsanto all use dicamba salt as the active ingredient, but formulating ingredients are proprietary. It is the formulating ingredients that could make a difference in retaining dicamba residues.”
Liu has been fine-tuning his formulation based on his findings and is now getting ready for additional testing.
“Significant progress has been made, and it is time to move the work from the lab to fields,” he said. “If the field testing validates, the next step would be to approach product manufacturers and explore university-industry collaborations.”
The LSU AgCenter and the LSU College of Agriculture