Abstract
A new insect growth regulator, PH 60-40 [N-(4-chlorophenyl)-N′-(2,6-difluorobenzoyl) urea] was tested on the mature larvae of the stable fly, Stomoxys calcitrans (L.), by a fly medium method and by hens as a feed additive. One ppm of PH 60-40 in the fly breeding medium gave almost complete inhibition of the cuticle formation of the flies during pupal metamorphosis. PH 60-40 also satisfactorily suppressed adult emergence from chicken manure at the same concentrations. Thus, PH 60-40 seems to be efficient for control of the stable fly.
