Submitted to: American Chemical Society Abstracts
Publication Type: Abstract Only
Publication Acceptance Date: December 29, 2004
Publication Date: March 10, 2005
Citation: Wauchope, R.D., Webster, T.M., Potter, T.L., Wade, L. 2005. Precision spray application for presistence and washoff studies of foliar pesticide residues: Method development. American Chemical Society Abstracts. 229:U86. Technical Abstract: Pesticide spray concentrations in the plant canopy are typically difficult to measure because of large variation in deposition from the typical sprayer. This high variability is a serious problem because a good description of the fate of pesticide residues on plant foliage residues is a fundamental need for predicting food residues and the environmental fate of many pesticides. One approach to this problem is to develop a high precision technique for measuring deposition of pesticide spray solutions on specific locations within the plant canopy. We are investigating a technique that uses a soluble fluorescent dye and digital graphic image analysis along with washoff experiments using both classical residue analysis and fluorescence spectrometry. Preliminary results suggest that we are able to precisely characterize absolute deposit amounts and their variability from point to point in a plant canopy, and as a consequence we are able to measure washoff and foliar persistence of deposits with much greater precision than previously reported.