|| 要旨トップ | 本企画の概要 |||日本生態学会第65回全国大会 (2018年3月、札幌) 講演要旨
シンポジウム S14-7 （Presentation in Symposium）
The recent increase of ground-level ozone (O3) may affect the quality of leaves and consequently affect the degree of grazing by insects. Using a free-air O3 enrichment system, we found lower grazing damages on leaves of Japanese white birch by alder leaf beetle under elevated O3. Contrary to the result found in the field, choice and non-choice style of feeding experiments showed that leaves exposed to elevated O3 were preferred by the leaf beetles due to lower defensive chemical production. To clarify this contradictory phenomenon, we pointed out the possibility of BVOC (Biogenic Volatile Organic Compounds) working as signal chemicals for insects to locate their host plants. In this research, two groups of BVOC, monoterpene (MT, C10H16) and sesquiterpene (SQT, C15H24) were of interest. Although many compounds were emitted from leaves of the birch, both MT and SQT had no significant difference in the basal emission rate regardless of O3 exposure. Therefore, BVOC emission in itself does not work as a factor that changes grazing activity of the leaf beetles, however, the blend ratio of BVOC should be considered. Under elevated O3, BVOC dynamics should be studied considering the reaction with O3 after emitted into the atmosphere.