スギ葉のモノテルペン放出に葉温と光強度が与える影響

抄録

We conducted laboratory and field measurements of monoterpene emissions from leaves of the Japanese conifer tree species (Cryptomeria japonica), which is one of the major tree species in Japan. To measure and identify monoterpenes emitted from the leaves, single branches of the trees were enclosed in a transparent PFA bag. In the laboratory experiment the photosynthetic photon flux density (PPFD) was controlled by changing the height of a metal halide lamp. The leaf temperature was controlled using a constant-temperature unit. Monoterpenes emitted by C. japonica were dominated by sabinene and α-pinene. The obtained data sets revealed that the emission rates of C. japonica highly correlated with leaf temperature, but did not correlate with PPFD. In the field measurements the basal emission rate (E_S) calculated by a temperature-dependent model ranged from 0.60 and 3.16 μg g^-1 h^-1. The compositions of monoterpene emission and the (E_S) values from leaves of young C. japonica were different between seasons.