Volatile and Within-Needle Terpene Changes to Douglas-fir Trees Associated With Douglas-fir Beetle (Coleoptera: Curculionidae) Attack.

摘要: Mass attack by tree-killing bark beetles (Curculionidae: Scolytinae) brings about large chemical changes in host trees that can have important ecological consequences. For example, mountain pine beetle ( Dendroctonus ponderosae Hopkins) increases emission of terpenes lodgepole Pinus contorta Dougl. ex Loud.), affecting foliage flammability with consequences for wildfires. In this study, we measured to Douglas-fir Pseudotsuga menziesii var. glauca (Mirb.) Franco) response pseudotsugae as die and crowns transitioned from green/healthy, green-infested (year attack), yellow after red (2 yr attack). We found differences volatile within-needle terpene concentrations among crown classes variation across a growing season. general, emissions total individual were greater needles than green needles. increased compounds linked tree other conifer species known attract (e.g., α -pinene, camphene, D-limonene). There was little relationship between air temperature or terpenes, suggesting passive dead foliage) does not fully explain emissions. The potential physiological causes these beetle-associated are discussed.