Competition Between Anisopteromalus calandrae and Choetospila elegans (Hymenoptera: Pteromalidae) at Different Parasitoid Densities on Immature Maize Weevils (Coleoptera: Curculionidae) in Corn

Immature maize weevils, Sitophilus zeamais Motschulsky, in corn were exposed to Anisopteromalus calandrae (Howard) alone, Choetospila elegans Westwood alone, or a combination of both species. Anisopteromalus calandrae was much more efficient at parasitizing immature maize weevils in corn than was C. elegans. The combination of A. calandrae plus C. elegans had similar effects as A. calandrae alone on total maize weevil mortality for equal numbers of parasitoids. Under interspecific competition, the emergence of C. elegans progeny and their sex ratio (percentage female) were significantly reduced in the presence of A. calandrae, but A. calandrae was not affected substantially by C. elegans.