<?xml version="1.0" encoding="UTF-8"?><xml><records><record><source-app name="Biblio" version="7.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Loreto, F</style></author><author><style face="normal" font="default" size="100%">Ciccioli, P</style></author><author><style face="normal" font="default" size="100%">Cecinato, A</style></author><author><style face="normal" font="default" size="100%">Brancaleoni, E</style></author><author><style face="normal" font="default" size="100%">Frattoni, M</style></author><author><style face="normal" font="default" size="100%">Fabozzi, C</style></author><author><style face="normal" font="default" size="100%">Tricoli, D</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Evidence of the photosynthetic origin of monoterpenes emitted by Quercus ilex L leaves by C-13 labeling</style></title><secondary-title><style face="normal" font="default" size="100%">PLANT PHYSIOLOGY</style></secondary-title></titles><keywords><keyword><style  face="normal" font="default" size="100%">alpha-pinene</style></keyword><keyword><style  face="normal" font="default" size="100%">C-13 labeling</style></keyword><keyword><style  face="normal" font="default" size="100%">Emissions</style></keyword><keyword><style  face="normal" font="default" size="100%">isoprene</style></keyword><keyword><style  face="normal" font="default" size="100%">Monoterpenes</style></keyword><keyword><style  face="normal" font="default" size="100%">Quercus flex L.</style></keyword><keyword><style  face="normal" font="default" size="100%">Quercus ilex</style></keyword></keywords><dates><year><style  face="normal" font="default" size="100%">1996</style></year></dates><publisher><style face="normal" font="default" size="100%">AMER SOC PLANT PHYSIOLOGISTS</style></publisher><pub-location><style face="normal" font="default" size="100%">15501 MONONA DRIVE, ROCKVILLE, MD 20855</style></pub-location><volume><style face="normal" font="default" size="100%">110</style></volume><pages><style face="normal" font="default" size="100%">1317-1322</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">The carbon of the four main monoterpenes emitted by Quercus flex L. leaves was completely labeled with C-13 after a 20-min feeding with 99% (CO2)-C-13. This labeling time course is comparable with the labeling time course of isoprene, the terpenoid emitted by other Quercus species and synthesized in leaf chloroplasts. It is also comparable with that of phosphoglyceric acid. Our experiment therefore provides evidence that monoterpenes emitted by Q. ilex are formed from photosynthesis intermediates and may share the same synthetic pathway with isoprene. By analyzing the rate and the distribution of labeling in the different fragments, we looked for evidence of differential carbon labeling in the alpha-pinene emitted. However, the labeling pattern was quite uniform in the different fragments, suggesting that the carbon skeleton of the emitted monoterpenes comes from a unique carbon source.</style></abstract><notes><style face="normal" font="default" size="100%">APS</style></notes><research-notes><style face="normal" font="default" size="100%">APS</style></research-notes></record><record><source-app name="Biblio" version="7.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Loreto, F</style></author><author><style face="normal" font="default" size="100%">Ciccioli, P</style></author><author><style face="normal" font="default" size="100%">Cecinato, A</style></author><author><style face="normal" font="default" size="100%">Brancaleoni, E</style></author><author><style face="normal" font="default" size="100%">Frattoni, M</style></author><author><style face="normal" font="default" size="100%">Tricoli, D</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Influence of environmental factors and air composition on the emission of alpha-pinene from Quercus ilex leaves</style></title><secondary-title><style face="normal" font="default" size="100%">PLANT PHYSIOLOGY</style></secondary-title></titles><keywords><keyword><style  face="normal" font="default" size="100%">alpha-pinene</style></keyword><keyword><style  face="normal" font="default" size="100%">photosynthesis</style></keyword><keyword><style  face="normal" font="default" size="100%">Quercus ilex</style></keyword></keywords><dates><year><style  face="normal" font="default" size="100%">1996</style></year></dates><publisher><style face="normal" font="default" size="100%">AMER SOC PLANT PHYSIOLOGISTS</style></publisher><pub-location><style face="normal" font="default" size="100%">15501 MONONA DRIVE, ROCKVILLE, MD 20855</style></pub-location><volume><style face="normal" font="default" size="100%">110</style></volume><pages><style face="normal" font="default" size="100%">267-275</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">We studied the emission of alpha-pinene from Quercos ilex leaves. Only the abaxial side of the hypostomatous Q. ilex leaf emits alpha-pinene. Light induced photosynthesis and alpha-pinene emission. However, the response of photosynthesis to dark-to-light transitions was faster than that of alpha-pinene, suggesting that ATP controls the emission. The emission was higher at 30 than at 20 degrees C, whereas photosynthesis did not change. Therefore, the relationship between photosynthesis and alpha-pinene emission does not always hold. When CO2 was removed from the air, transpiration was stimulated but photosynthesis and alpha-pinene emission were inhibited. alpha-Pinene inhibition was more rapid under low O-2. When CO2 in the air was increased, photosynthesis was stimulated and transpiration was reduced, but alpha-pinene emission was unaffected. Therefore, the emission depends on the availability of photosynthetic carbon, is not saturated at ambient CO2, and is not dependent on stomatal opening. The pattern of alpha-pinene emission from Q. ilex is different from that of plants having specialized structures for storage and emission of terpenes. We suggest that alpha-pinene emitted by Q. ilex leaves is synthesized in the chloroplasts and shares the same biochemical pathway with isoprene emitted by isoprene-emitting oak species.</style></abstract><notes><style face="normal" font="default" size="100%">APS</style></notes><research-notes><style face="normal" font="default" size="100%">APS</style></research-notes></record></records></xml>