Leaf volatiles from nonhost deciduous trees : Variation by tree species, season and temperature, and electrophysiological activity in Ips typographus
The leaf volatiles emitted from four nonhost tree species of lps typographus, i.e. Betula pendula, B. pubescens, Populus tremula, and Sambucus nigra, were collected outdoors by headspace sampling in situ and analyzed by GC-MS. Three major classes of compounds, aliphatics [mainly green-leaf volatiles (GLVs)], monoterpenes, and sesquiterpenes, existed in all the deciduous tree species investigated.