Tabanone was most active on duckweed species but was
much less effective against garden lettuce and garden onion.
This difference may be due to its lipophilic physicochemical
properties. Indeed, tabanone has a calculated (ACD Labs,
Toronto, Ontario, Canada M6C 1T4) log P value of 3.588.
Its low water solubility prevented it from dissolving in the
duckweed growth medium and instead formed a film on the
surface. Therefore, the actual concentration on the surface of
the medium was probably much higher than the intended
final concentration, resulting in an artificially higher level of activity. However, in soil, one would expect such a lipophilic
compound to adhere to soil particles, producing microenvironments
of high concentration, similar to that of highly
lipophilic, soil-applied herbicides (e.g., dinitroanilines).