We compared the role of instantaneous temperature and temperature history in the determination of α-pinene emissions in Mediterranean conifer Pinus halepensis that stores monoterpenes in resin ducts, and in Mediterranean broad-leaved evergreen Quercus ilex that lacks such specialized storage structures. In both species, α-pinene emission rates (E) exhibited a significant exponential correlation with leaf temperature and the rates of photosynthetic electron transport (JCO 2 +O 2 ) started to decrease after an optimum at approximately 35 o C. However, there was a higher dependence of E on mean temperature of previous days than on mean temperature of current day for P. halepensis but not for Q. ilex. JCO 2 +O 2 showed a maximum relationship to mean temperature of previous 3 and 5 days for P. halepensis and Q. ilex respectively. We conclude that although the best correlation of emission rates were found for instantaneous foliar temperatures, the effect of accumulated previous temperature con

Our research on volatile compound emissions has been supported by the funding from the European Science Foundation (Programme VOCBAS), the European Commission Marie Curie research training network ISONET (MC-RTN-CT-2003 504720), the Spanish Government (CGL2006-04025/BOS and ConsoliderIngenio Montes CSD 2008-00040), the Catalan Government (SGR 2009-458), the Spanish National Research council (CSIC-PIF08- 006-3), the Estonian Science Foundation (grant 7645) and the Estonian Ministry of Education and Science (SF1090065s07)

6 páginas,4 figuras.

Peer reviewed