Oviposition behavior of Ostrinia nubilalis (Lepidoptera: Crambidae) in response to potential intra- and interspecific interactions

Abstract

Oviposition behavior is an important mechanism for establishing spatial distribution and mitigating potential interactions among community members. We studied the oviposition behavior of the European corn borer, Ostrinia nubilalis Hübner, in the presence of conspecific larvae, the aphid Rhopalosiphum maidis (Fitch), and corn pollen to determine whether these potential interacting factors affect the distribution of European corn borer egg masses laid on sweet corn in field cages. We found that ovipositing females in the field differentiate between adjacent corn plants in response to conspecific larvae. We also found that European corn borers laid significantly fewer egg masses on plants with large aphid colonies compared with adjacent plants with few aphids. Furthermore, fewer egg masses were laid on the top one third of the plant where the aphid colonies were located. We also tested for a fitness advantage of European corn borer's oviposition behavior in response to aphids and found that neonate larvae inoculated on plants with small aphid colonies had higher establishment (survivorship + retention) than larvae on plants with large aphid colonies. Pollen, disentangled from any effects of differential plant stage, did not seem to affect oviposition behavior. These results may have important implications for understanding the spatial distribution and interaction of European corn borer, its natural enemies, and potential management strategies.