Natural distribution of parasitoids of Spodoptera frugiperda (Lepidoptera: Noctuidae) larvae in Argentina

MURÚA, M. G., MOLINA-OCHOA, J. AND HIDALGO, P.

JOURNAL OF INSECT SCIENCE

University of Wisconsin Digital Collections Center and the UW-Madison Libraries' Office of Scholarly Communication and Publishing

Año: 2009 vol. 9 p. 1 - 17

1536-2442

To develop a better understanding of the natural distribution and to update the knowledge of the incidence of the complex of parasitoids of the fall armyworm (FAW), Spodoptera frugiperda (Smith), samplings in whorl-stage corn were carried out in provinces of Argentina from 1999 to 2003. FAW larvae were collected from corn in localities of the provinces of Tucumán, Salta, Jujuy, Santiago del Estero, La Rioja, Córdoba, San Luis, Chaco and Misiones. In each locality 30 corn plants were sampled and only larvae located in those plants were collected. The parasitoids that emerged from FAW larvae were identified and counted. The abundance of the parasitoids and the parasitism rate were estimated. The FAW parasitoids collected were Campoletis grioti (Blanchard), Chelonus insularis (Cresson), Archytas marmoratus (Town.) and/or A. incertus (Macquart), Ophion sp., Euplectrus platyhypenae Howard, and Incamyia chilensis (Blanchard). C. grioti was the most abundant and frequent during the five-year survey. Similar diversity of parasitoids was obtained in all the provinces, with the exception of I. chilensis and E. platyhypenae which were recovered only in the province of Salta. In the Northwestern region, in Tucumán, C. grioti and species of Archytas were the most abundant and frequent parasitoids. On the contrary, in Salta and Jujuy Ch. insularis was the parasitoid most abundant and frequently recovered. The parasitism rate obtained in Tucumán, Salta and Jujuy provinces were 21.96%, 17.87% and 6.63% respectively with an average of 18.93%. Our results demonstrate that hymenopteran and dipteran parasitoids of FAW occurred differentially throughout the Argentinian provinces and played an important role on the natural control of the FAW larval population.