Volatiles induced by the larvae of the Asian corn borer (Ostrinia furnacalis) in maize plants affect behavior of conspecific larvae and female adults

Abstract

Abstract Effects of maize (Zea mays L.) volatiles induced by larvae of the Asian corn borer, Ostrinia furnacalis (Guenée), on the orientation behaviors of Asian corn borer larvae and oviposition of the females were investigated. Nineteen volatile chemicals, with terpenes being the major components, were identified from maize plants attacked by third instar Asian corn borer larvae. Coupled gas chromatographic‐electroantennographic detection (GC‐EAD) analyses revealed some electroantennographic differences between female and male Asian corn borer antennae in response to larvae‐induced maize volatiles; female responded to (E)‐2‐hexenal, nonanal, (Z)‐3‐hexen‐1‐ol and three unknown compounds while the male only responded to (E)‐2‐hexenal, nonanal and one unknown compound. In laboratory orientation bioassays, Asian corn borer neonate larvae were attracted to extracts collected from Asian corn borer‐damaged plants as well as to synthetic farnesene, but were repelled by (Z)‐3‐hexen‐1‐ol. In laboratory oviposition bioassays, gravid females laid fewer eggs on plants damaged by larvae than on mechanically damaged plants or undamaged plants. Adult Asian corn borer females deposited fewer eggs on wax paper treated with (E)‐2‐hexenal or (Z)‐3‐hexen‐1‐ol than on wax paper treated with hexane (control). The results suggest that Asian corn borer can affect the behaviors of conspecific larvae and adults by changing host plant volatiles.