Volatiles from Eucalyptus Trunks and Forest Floor Humus Influence the Habitat Transfer, Host Selection, and Aggregation of Endoclita signifer Larvae

Endoclita signifer is a major wood-boring pest of eucalyptus trees in China, and its third instar larvae can accurately find infest mixed-species forests, although it also feed on another 51 tree species the same planted area. A total 34 volatile compounds were identified from trunks, including non-infested infested trunks with single or multiple (more than three) larval entrance cover packets, forest floor humus. Of these, o-cymene showed strong gas chromatography-electroantennographic detection (GC-EAD) activity significant attraction E. larvae. Higher abundance alpha-phellandrene, o-cymene, unique 2-phenyl-2-propanol profile indicated that they herbivore-induced plant volatiles (HIPVs). The significantly higher to blends, especially those volatiles. blend three HIPVs, α-pinene, D-limonene, n-butyl ether may serve as an attractant for control plantations. Further, exposure some these which elicited electroantennogram behavioral responses, influenced expressions olfactory proteins. Our results show recognize host are attracted trunk by HIPVs when shift their habitats humus trunks.