<?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></contributors><titles><title><style face="normal" font="default" size="100%">A hypothesis on the evolution of isoprenoid emission by oaks based on the correlation between emission type and Quercus taxonomy</style></title><secondary-title><style face="normal" font="default" size="100%">Oecologia</style></secondary-title></titles><dates><year><style  face="normal" font="default" size="100%">1998</style></year></dates><volume><style face="normal" font="default" size="100%">115</style></volume><pages><style face="normal" font="default" size="100%">302-305</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">We show that Mediterranean oaks that emit isoprene, monoterpenes or no isoprenoids belong to dierent subgenera as indicated by morpho-taxonomy and molecular genetics. On the other hand, oaks from North America and Asia that are taxonomically similar to the Mediterranean monoterpene emitter Q. ilex emit isoprene only. We surmise that isoprene emission is a genetic character which evolved ancestrally in the oak genus since this is the prevalent emission type in oaks widespread around the world and adapted to dierent environments. This ancestral character may have been either lost or modi®ed in more recent clades such as those originating the Mediterranean oaks. If our hy- pothesis is correct then the taxonomy of European oaks is validated by this independent trait. Isoprenoid emis- sion could serve as a chemo-taxonomical marker and could be used to reconstruct the phylogeny of oaks in association with molecular markers.</style></abstract></record><record><source-app name="Biblio" version="7.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors></contributors><titles><title><style face="normal" font="default" size="100%">Measurement of isoprenoid content in leaves of Mediterranean Quercus spp. by a novel and sensitive method and estimation of the isoprenoid partition between liquid and gas phase inside the leaves</style></title><secondary-title><style face="normal" font="default" size="100%">Plant Science</style></secondary-title></titles><dates><year><style  face="normal" font="default" size="100%">1998</style></year></dates><volume><style face="normal" font="default" size="100%">136</style></volume><pages><style face="normal" font="default" size="100%">25-30</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">We used a novel. simple and sensitive method to extract isoprenoids contained in the leaves and compared emission and content of isoprenoids in the leaves of three Mediterranean oak species emitting isoprene (Quercus puhcsccws), monoterpenes (Querc~s ilrs) or non-emitting isoprenoids (Quercus cerris). The content is qualitatively consistent with the emission of isoprenoids by Qucrczls spp. However. the fraction of isoprenoids in the gas phase was estimated to be r 0.02 and 5% of the total content for monoterpenes and isoprene, respectively. On the other hand, the content of monoterpenes in the leaf was much higher than that of isoprene and particularly rich of compounds which can hardly be detected in an emission such as linalool. It is concluded that isoprenoids are contained in temporary pools and that the different partition between gas and liquid phases plays an important role in determining the pool size in isoprene and monoterpene-emitting oaks. The pools of isoprenoid-emitting oaks sustain the emission for few minutes when isoprenoid formation is prevented. which rules out the presence of specialized organs for isoprenoid storage and are absent altogether in non-emitting species.</style></abstract></record><record><source-app name="Biblio" version="7.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors></contributors><titles><title><style face="normal" font="default" size="100%">Use of the isoprene algorithm for predicting the monoterpene emission from the Mediterranean holm oak Quercus ilex L.: Performance and limits of this approach</style></title><secondary-title><style face="normal" font="default" size="100%">Journal of Geophysical Research: Atmospheres</style></secondary-title></titles><dates><year><style  face="normal" font="default" size="100%">1997</style></year></dates><volume><style face="normal" font="default" size="100%">102</style></volume><pages><style face="normal" font="default" size="100%">23319-23328</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">The algorithm developed by Guenther et al. [1991] to describe the organic emission of isoprene-emitting plants has been used for predicting monoterpene emission from Quercus ilex L., an evergreen oak typical of the Mediterranean basin. The dependence of monoterpene emission on photosynthetically active radiation and temperature has been verified through laboratory experiments carried out on single leaves as well as through field measurements at branch level. While the algorithm describes well monoterpene emission under stationary state conditions, it is less accurate when rapid fluctuations of light and temperature take place. Because of this, the isoprene algorithm is capable of predicting the response of Quercus ilex L. with an accuracy better than ±25% only in 65% of the environmental situations experienced by the plant. Field and laboratory observations consistently indicate that temperature oscillations can be an important source for the discrepancies between predicted and observed values as they can generate bursts of emission with values twice as high as those predicted by the algorithm. Possible causes generating these effects are analyzed and critically discussed. In spite of the observed limitations, the isoprene algorithm can successfully describe the biogenic emission from Quercus ilex L., and its use is advantageous as it greatly simplifies regional and global emission models, especially if the light dependence of monoterpene emission is proven to be a widespread phenomenon.</style></abstract></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%">Ciccioli, Paolo</style></author><author><style face="normal" font="default" size="100%">Fabozzi, Concetta</style></author><author><style face="normal" font="default" size="100%">Brancaleoni, Enzo</style></author><author><style face="normal" font="default" size="100%">Cecinato, Angelo</style></author><author><style face="normal" font="default" size="100%">Frattoni, Massimiliano</style></author><author><style face="normal" font="default" size="100%">Loreto, Francesco</style></author><author><style face="normal" font="default" size="100%">Kesselmeier, Jürgen</style></author><author><style face="normal" font="default" size="100%">Schäfer, Luise</style></author><author><style face="normal" font="default" size="100%">Bode, Kirsten</style></author><author><style face="normal" font="default" size="100%">Torres, Liberto</style></author><author><style face="normal" font="default" size="100%">Fugit, Jean-Luc</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Use of the isoprene algorithm for predicting the monoterpene emission from the Mediterranean holm oak Quercus ilex L.: Performance and limits of this approach</style></title><secondary-title><style face="normal" font="default" size="100%">Journal of Geophysical Research: Atmospheres</style></secondary-title></titles><keywords><keyword><style  face="normal" font="default" size="100%">Biogenic emission</style></keyword><keyword><style  face="normal" font="default" size="100%">isoprene algorithm</style></keyword><keyword><style  face="normal" font="default" size="100%">monoterpene (voyant)</style></keyword><keyword><style  face="normal" font="default" size="100%">Quercus ilex</style></keyword><keyword><style  face="normal" font="default" size="100%">Temperature</style></keyword></keywords><dates><year><style  face="normal" font="default" size="100%">1997</style></year><pub-dates><date><style  face="normal" font="default" size="100%">1997///</style></date></pub-dates></dates><urls><web-urls><url><style face="normal" font="default" size="100%">http://dx.doi.org/10.1029/97JD01372</style></url></web-urls></urls><volume><style face="normal" font="default" size="100%">102</style></volume><pages><style face="normal" font="default" size="100%">23319 - 23328</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">The algorithm developed by Guenther et al. [1991] to describe the organic emission of isoprene-emitting plants has been used for predicting monoterpene emission from Quercus ilex L., an evergreen oak typical of the Mediterranean basin. The dependence of monoterpene emission on photosynthetically active radiation and temperature has been verified through laboratory experiments carried out on single leaves as well as through field measurements at branch level. While the algorithm describes well monoterpene emission under stationary state conditions, it is less accurate when rapid fluctuations of light and temperature take place. Because of this, the isoprene algorithm is capable of predicting the response of Quercus ilex L. with an accuracy better than ±25% only in 65% of the environmental situations experienced by the plant. Field and laboratory observations consistently indicate that temperature oscillations can be an important source for the discrepancies between predicted and observed values as they can generate bursts of emission with values twice as high as those predicted by the algorithm. Possible causes generating these effects are analyzed and critically discussed. In spite of the observed limitations, the isoprene algorithm can successfully describe the biogenic emission from Quercus ilex L., and its use is advantageous as it greatly simplifies regional and global emission models, especially if the light dependence of monoterpene emission is proven to be a widespread phenomenon.</style></abstract><issue><style face="normal" font="default" size="100%">D19</style></issue></record></records></xml>