Effects of water stress on plant volatile emission and insect oviposition preference in an agroecosystem

Abstract

1. Drought has become more common and severe in many parts of the world due to climate change. The effect of water stress on insect oviposition preference that is key determinant for their fitness has received less attention.2. Here, we examined how water stress may affect oviposition selection of Ostrinia furnacalis for maize plants in the greenhouse, and tested difference in volatile compounds emitted from treated maize, and electronantennogram and bioassay responses of O. furnacalis to the volatile profiles in maize plants.3. Ostrinia furnacalis were more prone to lay eggs on the well-watered maize. Most plant volatile compounds differed significantly among the three water treatments, including increased emissions of β-caryophyllene, (E)-2-hexenal, and linalool, and decreased emission of (Z)-3-hexen-1-ol when subjected to increasing intensity of drought. Varied volatile profiles of maize may drive oviposition decision of O. furnacalis,because O. furnacalis showed a clear oviposition preference for (Z)-3-hexen-1-ol, while not for β-caryophyllene, (E)-2-hexenal, and linalool, at the concentration of 1000 ppm.5. This study advances understanding of drought effects on plant-insect interactions through volatile profiles. Our finding calls for attention to oviposition selection for insect pest management in agricultural settings, especially in regions under changing precipitation patterns.