Effect of the juvenile hormone analogue fenoxycarb applied via the host on the parasitoid Phanerotoma (Phanerortoma) ocularis Kohl (Hym. Braconidae)

Abstract Concentrations of 0.001, 0.005, 0.01, 0.05 and 0.1 μg/ml of fenoxycarb (Ro 13-5223) were applied topically to larvae of Ephestia kuehniella Zeller parasitized by Phanerotoma (Phanerotoma) ocularis Kohl. The effect of the treatment and concentration on parasitism rates, preimaginal mortality and emergence rates of the parasitoid were studied comparatively for each larval instar of the host considered. The preimaginal mortality was high when the fenoxycarb was applied on the first larval instar of the host (23–46%) and more higher when applied to the sixth larval instar of the host (40–86%). Consequently, fenoxycarb treatment of the last larval instar of the host produced a reduction…