Zur Wirkung zweier Juvenilhormon-Analogen auf die Baumwolleule Spodoptera littoralis (Boisd.) (Lep., Noctuidae)

Effects of two juvenile hormone mimics on the Egyptian Cotton Leaf-Worm, Spodoptera littoralis (Boisd.) (Lep., Noctuidae)Two analogues of insect juvenile hormone were tested for effects on eggs, 6th instars, and pupae ofSpodoptera littoralis (Boisd.). These were 3,7-dimethyl-6-epoxy-2-nonene-1-oxy (3,4-methylene-dioxybenzene), and 3,7-dimethyl-6-epoxy-2-nonene-1-oxy (4-chlorobenzene). The purpose was to observe effects of these chemical on fecundity, metamorphosis, and survival. Against 24-hour-old eggs the chloro-derivative was much more potent inhibitor of embryonic development than its methylene dioxy-analogue. Against 6th instar larvae these two compounds were equipotent in resulting intermediate forms incapable of survival. Against pupae these two analogues at 6–8 g/insect caused deformities and reduced fecundity and fertility of the survival adults to more than 90% of their normal levels.