<?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%">Guidi, Lucia</style></author><author><style face="normal" font="default" size="100%">Calatayud, Angeles</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Non-invasive tools to estimate stress-induced changes in photosynthetic performance in plants inhabiting Mediterranean areas</style></title><secondary-title><style face="normal" font="default" size="100%">Environmental and Experimental Botany</style></secondary-title></titles><keywords><keyword><style  face="normal" font="default" size="100%">Abiotic stress</style></keyword><keyword><style  face="normal" font="default" size="100%">Chlorophyll a fluorescence</style></keyword><keyword><style  face="normal" font="default" size="100%">climate change</style></keyword><keyword><style  face="normal" font="default" size="100%">Gas exchange</style></keyword><keyword><style  face="normal" font="default" size="100%">Oxidative stress</style></keyword><keyword><style  face="normal" font="default" size="100%">photosynthesis</style></keyword></keywords><dates><year><style  face="normal" font="default" size="100%">2013</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2013///</style></date></pub-dates></dates><urls><web-urls><url><style face="normal" font="default" size="100%">http://dx.doi.org/10.1016/j.envexpbot.2013.12.007http://www.sciencedirect.com/science/article/pii/S0098847213002189</style></url></web-urls></urls><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">In Mediterranean areas, plants are concomitantly exposed to various abiotic stresses such as light intensity, water deficit, extremes in air temperature, air pollutants, etc. These environmental pressures adversely affect plant development. Changes in photosystem activity are an early response of plants to abiotic stresses. Therefore, chlorophyll (Chl) fluorescence and gas exchange, two non-invasive, rapid and inexpensive techniques for measuring photosynthesis in leaves, have been widely used by plant ecophysiologists to analyse plant responses to stressful conditions. Chl a fluorescence and gas exchange parameters can be indeed used to evaluate changes in photochemical and non-photochemical processes in photosystems associated with electron transport, CO2 fixation, and heat dissipation. In this review, we focus our analysis on the effects of different abiotic stresses on the photochemistry of Mediterranean plants using Chl a fluorescence and gas exchange measurements. Since changes in photosynthetic parameters are observed in the absence of visual injuries, these methodologies constitute fundamental tools to predict and evaluate the extent to which abiotic stresses damage photosynthesis.</style></abstract><notes><style face="normal" font="default" size="100%">The following values have no corresponding Zotero field:&lt;br/&gt;publisher: Elsevier B.V.</style></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%">Bussotti, Filippo</style></author><author><style face="normal" font="default" size="100%">Desotgiu, Rosanna</style></author><author><style face="normal" font="default" size="100%">Cascio, Chiara</style></author><author><style face="normal" font="default" size="100%">Pollastrini, Martina</style></author><author><style face="normal" font="default" size="100%">Gravano, Elisabetta</style></author><author><style face="normal" font="default" size="100%">Gerosa, Giacomo</style></author><author><style face="normal" font="default" size="100%">Marzuoli, Riccardo</style></author><author><style face="normal" font="default" size="100%">Nali, Cristina</style></author><author><style face="normal" font="default" size="100%">Lorenzini, Giacomo</style></author><author><style face="normal" font="default" size="100%">Salvatori, Elisabetta</style></author><author><style face="normal" font="default" size="100%">Manes, Fausto</style></author><author><style face="normal" font="default" size="100%">Schaub, Marcus</style></author><author><style face="normal" font="default" size="100%">Strasser, Reto J.</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Ozone stress in woody plants assessed with chlorophyll a fluorescence. A critical reassessment of existing data</style></title><secondary-title><style face="normal" font="default" size="100%">Environmental and Experimental Botany</style></secondary-title></titles><keywords><keyword><style  face="normal" font="default" size="100%">Chlorophyll a fluorescence</style></keyword><keyword><style  face="normal" font="default" size="100%">OKJIP transient</style></keyword><keyword><style  face="normal" font="default" size="100%">Open top chambers</style></keyword><keyword><style  face="normal" font="default" size="100%">Ozone stress</style></keyword><keyword><style  face="normal" font="default" size="100%">Performance index</style></keyword><keyword><style  face="normal" font="default" size="100%">Quantum yield efficiency</style></keyword><keyword><style  face="normal" font="default" size="100%">Reaction centres</style></keyword><keyword><style  face="normal" font="default" size="100%">Visible foliar symptoms</style></keyword></keywords><dates><year><style  face="normal" font="default" size="100%">2011</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2011///</style></date></pub-dates></dates><urls><web-urls><url><style face="normal" font="default" size="100%">http://linkinghub.elsevier.com/retrieve/pii/S0098847210002200</style></url></web-urls></urls><volume><style face="normal" font="default" size="100%">73</style></volume><pages><style face="normal" font="default" size="100%">19 - 30</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">This paper proposes an overall reassessment of results from ﬂuorescence transient (FT) and modulated ﬂuorescence (MF) analysis on tree species subjected to treatment with ozone. Findings from literature and open-top chamber experiments were used in this review, in order to identify damage mechanisms and repair/avoidance strategies. Main results are summarised below. (i) The most widely used parameter to assess the response to ozone treatment was the quantum yield of primary photochemistry in the dark-adapted state (ϕPo, or FV/FM). This parameter proved to be very stable in stress and control conditions. Ozone-induced stress – and the related loss of photosynthetic efﬁciency and performance – was characterized by the change occurring in all parameters connected with the controlled dissipation: reduction of FM, FV/FM, RC/CS0 (in the ﬂuorescence transient analysis) and NPQ (in theMF analysis). This can be considered as a down-regulationmechanism aimed at lowering the electron supply as a consequence of a reduced demand from the Calvin cycle. (ii) The FT analysis revealed a change in the I–P region shape, indicating that events beyond PSI are affected. These events include a lesser density of PSI itself and the compromised ability of the end acceptors of electrons (ferredoxine, NADP + ) and RuBP to manage effectively the ﬂux of electrons. This behaviour may create an imbalance between electrons sent by the electron transport chain and those reaching the acceptors beyond PSI. Free electrons (those coming from PSI, but that do not reach the end acceptors) can activate the oxygen from fundamental to excited status, with production of ROS (Reactive Oxygen Species), thus inducing photo-oxidation processes of the cellular content. (iii) In many cases a temporarily enhanced efﬁciency of electron trapping and transport (expressed by the parameters FV/FM, ET/TR, PIABS, pQ) in PSII system has been observed. That efﬁciency has been connected to the triggering of repair processes, but when it is connected to a reduced end acceptor capacity in combination with reduced Calvin cycle energy demand lead to over-excitation of the photosynthetic apparatus and initiates response towards visible foliar injury. (iv) The behaviour of F0 can help us distinguish between different response strategies. The increase of F0 observed in some ozone-treated plant species is considered an expression of irreversible damage in PSII, whereas lowered values of this parameter may indicate the activation of PSII in the cells surrounding the damaged one, as part of a compensative process. Future directions for the research in this ﬁeld concern: (i) the possibility to combine ﬂuorescence parameters with carbon assimilation and growth to support the study on critical levels and (ii) the analysis of the events concerning the activity of PSI and the events leading to the ﬁxation of CO2, by using innovative technologies</style></abstract><notes><style face="normal" font="default" size="100%">The following values have no corresponding Zotero field:&lt;br/&gt;publisher: Elsevier B.V.</style></notes></record></records></xml>