|Cox, Lucia - UNIVERSITY OF MINNESOTA|
|Yen, Pau - BAYER CORPORATION|
Submitted to: Agronomy Abstracts
Publication Type: Abstract Only
Publication Acceptance Date: November 4, 1996
Publication Date: N/A
Technical Abstract: Sorption-desorption of imidacloprid and the guanidine, guanidine-olefin, and urea metabolites in 3 soils was determined. Initial solution concentrations were 0.05-1.5 ug mL**1. Freundlich sorption Kfs were imidacloprid-guanidine greater than imidacloprid-olefin greater than imidacloprid greater than imidacloprid-urea in the 3 soils. Kf correlated to soil OC content with Kf-oc for imidacloprid-urea equals 203; imidacloprid equals 412; imidacloprid-olefin equals 2740; and imidacloprid- quanidine equals 3200. Freundlich isotherm slopes were significantly less than 1. Desorption was hysteretic for all chemicals in all soils. Sorption of imidacloprid determined at half its solubility (250 ug mL**-1) (Koc equals 77) greatly overpredicts potential leaching compared to Koc determined at field application rates (kf-oc equals 412).