Increase in isoprene and monoterpene emissions after re-watering of droughted Quercus ilex seedlings

Biologia Plantarum (Impact Factor: 1.69). 01/2009; 53(2):351-354. DOI: 10.1007/s10535-009-0065-4

ABSTRACT We followed the diurnal cycles of isoprenoid emissions from Quercus ilex seedlings under drought and after re-watering. We found that Quercus ilex, generally considered a non-isoprene emitter, also emitted isoprene although at low rates. The emission rates of isoprene
reached 0.37 ± 0.02 nmol m−2 s−1 in controls, 0.15 ± 0.03 nmol m−2 s−1 under drought and 0.35 ± 0.04 nmol m−2 s−1 after re-watering, while emission rates of monoterpenes reached 11.0 ± 3.0, 7.0 ± 1.0 and 23.0 ± 5.0 nmol m−2 s−1, respectively. Emission rates recovered faster after re-watering than photosynthetic rate and followed diurnal changes in
irradiance in controls and under drought, but in leaf temperature after re-watering.

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