ABSTRACT
Monoterpenes emitted from trees play important roles in atmospheric chemistry through the formation of secondary organic aerosols and photochemical oxidants. Because monoterpene emissions from broad-leaved trees have rarely been studied in Japan, we measured the monoterpene emission rates of 20 Acer and 14 Fagaceae species. If a good correlation is found between the monoterpene precursor (geranyl diphosphate, GDP) content and monoterpene emission rate, the GDP content analysis in leaves may be an optional and simplified method to estimate monoterpene emission capacity of trees. To test this hypothesis, we investigated the relationship between GDP content in leaves and monoterpene emission rate of 13 tree species. Six Acer and 7 Fagaceae species were found to be monoterpene emitters. Although all of the measured trees contained GDP in their leaves, the presence or absence of monoterpene emissions was different for different species. Among the monoterpene emitters, no clear relationship was found between the basal emission rate (temperature: 30°C, photosynthetic photon flux density: 1000 μmol m−2 s−1) and GDP content. The ratio of the basal emission rate to GDP content differed between tree species. Our study demonstrated that the GDP content did not relate to the presence or absence of monoterpene production and its emission rate. We suggest that the activity or expression of monoterpene synthase may affect monoterpene emissions from Acer and Fagaceae species.
Acknowledgments
This work was supported by The Botanical Research Grant of ICHIMURA Foundation for New Technology. We appreciate the helpful discussion with Dr. Sohei ITO and Shogo NAKANO at University of Shizuoka.
Disclosure statement
No potential conflict of interest was reported by the authors.