Native parasitoids ofDalbulus elimatusandDalbulus maidis(Hemiptera: Cicadellidae) in winter crops of central Mexico

Abstract

AbstractNative parasitoids of the adult Mexican corn leafhopper,Dalbulus elimatus(Ball), and corn leafhopper,Dalbulus maidis(Delong and Wolcott), are described and their rates of parasitism on maize,Zea maysL., common barley,Hordeum vulgareL., and sorghum,Sorghumbicolor(L.) Moench (Poaceae) in central Mexico are determined. The survey was conducted throughout an annual cycle, with sampling of the previous season's crops when they were available. Leafhoppers showing evidence of parasitism were reared individually in the laboratory to obtain adult parasitoids. AdultD. elimatuswere parasitized on winter maize, barley, and sorghum by the flyEudorylas subopacus(Loew) (Diptera: Pipunculidae) and the waspGonatopus bartlettiOlmi (Hymenoptera: Dryinidae), whereas adultD. maidiswere parasitized by these fly and wasp parasitoids on winter maize only. The highest rates of parasitism ofD. elimatusbyE. subopacuswere 57.4% on maize, 39.6% on barley, and 48.8% on sorghum. The highest rate of parasitism ofD. maidisbyE. subopacuswas 20.4% on maize. In contrast, the highest rates of parasitism ofD. elimatusbyG. bartlettiwere 9.4% on maize, 2.7% on barley, and 25.8% on sorghum. The highest rate of parasitism ofD. maidisbyG. bartlettiwas 7.1% on maize. These results indicate that winter crops are habitats ofE. subopacusandG. bartlettiduring the winter season. This is the first report ofD. elimatusandD. maidisbeing parasitized byE. subopacusand ofD. elimatusbeing parasitized byG. bartletti.