none Two blends of fall armyworm, Spodoptera frugiperda (J.E. Smith), pheromonal components were evaluated in the laboratory for possible close-range effects on mating and oviposition by Cotesia marginiventris (Cresson). Neither a two- nor a five-component blend had any significant effect on mating or parasitization of S. frugiperda larvae by this parasitoid. Dosages fo 200, 400, and 800 mu g were tested.