Egg parasitoids of the corn leafhopper, Dalbulus maidis, in the southernmost area of its distribution range

J Insect Sci. 2013:13:10. doi: 10.1673/031.013.1001.

Abstract

Egg parasitoids of the corn leafhopper, Dalbulus maidis (DeLong and Wolcott) (Hemiptera: Cicadellidae), were surveyed exposing sentinel eggs of the leafhopper along a latitudinal transect of 600 km in Argentina, the southernmost area of its distribution range. Four parasitoid species were obtained: the mymarids Anagrus breviphragma Soyka (Hymenoptera: Mymaridae), Anagrus flaveolus Waterhouse, and Polynema sp., and the trichogrammatid Pseudoligosita longifrangiata (Viggiani) (Hymenoptera: Trichogrammatidae). The low parasitism rate, low species richness, and high proportion of generalist egg parasitoids were quite clear in the southern distribution limit of the vector, in contrast to regions where corn crops are available all year round and there are continuous and overlapping generations of the pest. Further studies need to be done in order to determine the native host of the above egg parasitoids, the seasonal abundance, and the possible occurrence of other species affecting D. maidis populations in the studied area.

Los parasitoides de huevos de la chicharrita del maíz, Dalbulus maidis (DeLong and Wolcott), fueron estudiados exponiendo huevos trampas a lo largo de una transecta de 600 Km en Argentina, en su rango de distribución más austral. Cuatro especies de parasitoides fueron obtenidos: los mimaridos Anagrus breviphragma Soyka, Anagrus flaveolus Waterhouse, y Polynema sp., y el tricogrammatido Pseudoligosita longifrangiata (Viggiani). Una baja tasa de parasitoidismo, una baja riqueza de especies y una alta proporción de parasitoides de huevos generalistas, son bastante claros o evidentes en el limite de distribucion mas al sur de D. maidis, en contraste con las regiones donde el cultivo del maiz esta disponible durante todo el ano y las generaciones de la plaga son continuas y se superponen.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Chile
  • Female
  • Hemiptera / parasitology*
  • Ovum / parasitology*