Date of this Version
Aerial and overhead center-pivot irrigation system (chemigated) applications of chlorpyrifos 4 emulsifiable concentrate (EC) and fenvalerate 2.4EC significantly reduced numbers of first- and second-generation European corn borer, Ostrinia nubilalis Hubner, larvae in field corn, Zea mays L. The number of first-generation O. nubilalis larvae, pupae, or cavities per plant in plots chemigated with chlorpyrifos in 1984 was significantly less than in plots where chlorpyrifos was applied aerially. A similar trend was observed for fenvalerate in 1985. No significant differences among application methods were observed for second-generation O. nubilalis treatments. Chlorpyrifos and fenvalerate were effective O. nubilalis control agents but efficacy differences between these two insecticides were variable. Corn yields did not vary significantly among application methods.