|El-sayed, Ashraf - New Zealand Institute Of Plant & Food Research|
|Byers, John - Hebrew University Of Jerusalem|
|Judd, Gary - Agriculture And Agri-Food Canada|
|Suckling, David - New Zealand Institute Of Plant & Food Research|
Submitted to: Scientific Reports
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 11/1/2016
Publication Date: 11/28/2016
Citation: El-Sayed, A., Knight, A.L., Byers, J., Judd, G., Suckling, D. 2016. Caterpillar-induced plant volatiles attract conspecific adults in nature. Scientific Reports. doi:10.1038/srep37555.
Interpretive Summary: Effective, low-cost monitoring of tree fruit pests is an important component of developing integrated programs which can minimize the use of insecticides. Researchers at the USDA, ARS, Yakima Agricultural Research Laboratory, Wapato, WA in collaboration with researchers in New Zealand and Canada evaluated volatiles released by apple damaged by insect larvae and found that two compounds in combination with acetic acid were attractive for both moth sexes of several important moth pest of orchards in both New Zealand and North America. Information from this research supports the continued effort to develop even more effective lures that can be used in trap-based monitoring program for important moth pests in tree fruits.
Technical Abstract: Plants release volatiles in response to caterpillar feeding that attracts natural enemies of the herbivores, a tri-trophic interaction which has been considered an indirect plant defence against herbivores. The caterpillar-induced plant volatiles have been reported to repel or attract conspecific adult herbivores. However to date, no volatile signals have been chemically identified where conspecific adults were either repelled or attracted under field conditions. Apple seedlings uniquely released seven compounds including acetic acid, acetic anhydride, benzyl alcohol, benzyl nitrile, indole, 2-phenylethanol, and (E)-nerolidol only when infested by larvae of the light brown apple moth, Epiphyas postvittana. In field tests in New Zealand, a blend of two of these, benzyl nitrile and acetic acid, attracted a large number of conspecific male and female adult moths. In North America, male and female adults of the tortricid, oblique-banded leafroller, Choristoneura rosaceana, were most attracted to a blend of 2-phenylethanol and acetic acid. Both sexes of the eye-spotted bud moth, Spilonota ocellana, were highly attracted to a blend of benzyl nitrile and acetic acid. This study provides the first identification of caterpillar-induced plant volatiles that attract conspecific adult herbivores under natural conditions, challenging the expectation of herbivore avoidance by these induced volatiles.