育苗箱施用または湛水散布したイソプロチオランおよびフィプロニルの田面水，土壌，および稲体における挙動

We investigated the behavior of isoprothiolane and fipronil after nursery-box application and that of isoprothiolane after submerged application in an experimental paddy field. The concentrations of the pesticides and their metabolites were monitored in paddy water, soil, and rice plants. The distribution profile for isoprothiolane mass in the field differed greatly between the nursery-box and submerged applications. The nursery-box-applied pesticides were mostly distributed in soil near the transplanted rice seedlings (root zone), versus little distribution in paddy water and rice plants (