<?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%">Galle, Alexander</style></author><author><style face="normal" font="default" size="100%">Florez-Sarasa, Igor</style></author><author><style face="normal" font="default" size="100%">Aououad, Hanan El</style></author><author><style face="normal" font="default" size="100%">Flexas, Jaume</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">The Mediterranean evergreen Quercus ilex and the semi-deciduous Cistus albidus differ in their leaf gas exchange regulation and acclimation to repeated drought and re-watering cycles</style></title><secondary-title><style face="normal" font="default" size="100%">Journal of Experimental Botany</style></secondary-title></titles><keywords><keyword><style  face="normal" font="default" size="100%">acclimation</style></keyword><keyword><style  face="normal" font="default" size="100%">drought–recovery cycles</style></keyword><keyword><style  face="normal" font="default" size="100%">mesophyll and stomatal conductance</style></keyword><keyword><style  face="normal" font="default" size="100%">osmotic adjustment</style></keyword><keyword><style  face="normal" font="default" size="100%">photosynthetic limitation analysis</style></keyword><keyword><style  face="normal" font="default" size="100%">water use efﬁciency</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://jxb.oxfordjournals.org/content/62/14/5207.abstract</style></url></web-urls></urls><volume><style face="normal" font="default" size="100%">62</style></volume><pages><style face="normal" font="default" size="100%">5207 - 5216</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Plants may exhibit some degree of acclimation after experiencing drought, but physiological adjustments to consecutive cycles of drought and re-watering (recovery) have scarcely been studied. The Mediterranean evergreen holm oak (Q. ilex) and the semi-deciduous rockrose (C. albidus) showed some degree of acclimation after the first of three drought cycles (S1, S2, and S3). For instance, during S2 and S3 both species retained higher relative leaf water contents than during S1, despite reaching similar leaf water potentials. However, both species showed remarkable differences in their photosynthetic acclimation to repeated drought cycles. Both species decreased photosynthesis to a similar extent during the three cycles (20–40% of control values). However, after S1 and S2, photosynthesis recovered only to 80% of control values in holm oak, due to persistently low stomatal (gs) and mesophyll (gm) conductances to CO2. Moreover, leaf intrinsic water use efficiency (WUE) was kept almost constant in this species during the entire experiment. By contrast, photosynthesis of rockrose recovered almost completely after each drought cycle (90–100% of control values), while the WUE was largely and permanently increased (by 50–150%, depending on the day) after S1. This was due to a regulation which consisted in keeping gs low (recovering to 50–60% of control values after re-watering) while maintaining a high gm (even exceeding control values during re-watering). While the mechanisms to achieve such particular regulation of water and CO2 diffusion in leaves are unknown, it clearly represents a unique acclimation feature of this species after a drought cycle, which allows it a much better performance during successive drought events. Thus, differences in the photosynthetic acclimation to repeated drought cycles can have important consequences on the relative fitness of different Mediterranean species or growth forms within the frame of climate change scenarios.</style></abstract><issue><style face="normal" font="default" size="100%">14</style></issue><notes><style face="normal" font="default" size="100%">10.1093/jxb/err23310.1093/jxb/err233</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%">Domínguez Núñez, José Alfonso</style></author><author><style face="normal" font="default" size="100%">Planelles González, Rosa</style></author><author><style face="normal" font="default" size="100%">Rodríguez Barreal, José Antonio</style></author><author><style face="normal" font="default" size="100%">Saiz de Omeñaca González, José Antonio</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Influence of water-stress acclimation and Tuber melanosporum mycorrhization on Quercus ilex seedlings</style></title><secondary-title><style face="normal" font="default" size="100%">Agroforestry Systems</style></secondary-title></titles><keywords><keyword><style  face="normal" font="default" size="100%">á mineral nutrition á</style></keyword><keyword><style  face="normal" font="default" size="100%">black truffle á drought</style></keyword><keyword><style  face="normal" font="default" size="100%">Black trufﬂe</style></keyword><keyword><style  face="normal" font="default" size="100%">Drought hardening</style></keyword><keyword><style  face="normal" font="default" size="100%">Elastic adjustment</style></keyword><keyword><style  face="normal" font="default" size="100%">elastic adjustment á inoculation</style></keyword><keyword><style  face="normal" font="default" size="100%">hardening á</style></keyword><keyword><style  face="normal" font="default" size="100%">Inoculation</style></keyword><keyword><style  face="normal" font="default" size="100%">Mineral nutrition</style></keyword><keyword><style  face="normal" font="default" size="100%">Nursery</style></keyword><keyword><style  face="normal" font="default" size="100%">nursery á osmotic adjustment</style></keyword><keyword><style  face="normal" font="default" size="100%">osmotic adjustment</style></keyword></keywords><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2008///</style></date></pub-dates></dates><urls><web-urls><url><style face="normal" font="default" size="100%">http://link.springer.com/10.1007/s10457-008-9197-3http://www.springerlink.com/index/10.1007/s10457-008-9197-3</style></url></web-urls></urls><volume><style face="normal" font="default" size="100%">75</style></volume><pages><style face="normal" font="default" size="100%">251 - 259</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Mycorrhizal and non-mycorrhizal holm oak (Quercus ilex L.) seedlings inoculated with black trufﬂe (Tuber melanosporum) were grown under nursery conditions and subjected to drought hardening for 4 months in autumn and winter followed by irrigation for 10 days. Leaf water potential and stomatal conductance were monitored during the 4 months of drought. When the test was completed (March), measurements were made for each treatment (inoculated or non-inoculated), and watering regime (watered and water-stressed). Pressure–volume curves, osmotic potential at full turgor, osmotic potential at zero turgor and the tissue modulus of elasticity near full turgor were calculated. Mycorrhizal colonization and growth, and the content of the main mineral nutrients N, P, K, Ca and Mg were measured. Water stress affected plant growth, caused an elastic adjustment of the plant tissues, and decreased the P and K content, and inoculation improved the nitrogen content. Drought acclimation apparently achieved the goal of improving the drought tolerance of holm oak seedlings, without depressing ectomycorrhizal root colonization by T. melanosporum.</style></abstract><issue><style face="normal" font="default" size="100%">3</style></issue></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%">Otieno, D. O.</style></author><author><style face="normal" font="default" size="100%">Kurz-Besson, C.</style></author><author><style face="normal" font="default" size="100%">Liu, J.</style></author><author><style face="normal" font="default" size="100%">Schmidt, M. W. T.</style></author><author><style face="normal" font="default" size="100%">Do, R. Vale-Lobo</style></author><author><style face="normal" font="default" size="100%">David, T. S.</style></author><author><style face="normal" font="default" size="100%">Siegwolf, R.</style></author><author><style face="normal" font="default" size="100%">Pereira, J. S.</style></author><author><style face="normal" font="default" size="100%">Tenhunen, J. D.</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Seasonal Variations in Soil and Plant Water Status in a Quercus suber L. Stand: Roots as Determinants of Tree Productivity and Survival in the Mediterranean-type Ecosystem</style></title><secondary-title><style face="normal" font="default" size="100%">Plant and Soil</style></secondary-title></titles><keywords><keyword><style  face="normal" font="default" size="100%">Drought stress</style></keyword><keyword><style  face="normal" font="default" size="100%">leaf water potential</style></keyword><keyword><style  face="normal" font="default" size="100%">osmotic adjustment</style></keyword><keyword><style  face="normal" font="default" size="100%">oxygen isotope</style></keyword><keyword><style  face="normal" font="default" size="100%">root distribution</style></keyword></keywords><dates><year><style  face="normal" font="default" size="100%">2006</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2006///</style></date></pub-dates></dates><urls><web-urls><url><style face="normal" font="default" size="100%">http://www.springerlink.com/index/10.1007/s11104-004-7539-0</style></url></web-urls></urls><volume><style face="normal" font="default" size="100%">283</style></volume><pages><style face="normal" font="default" size="100%">119 - 135</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Studies were conducted to examine changes in soil (Ys) and plant water status during summer in a 16-year old Quercus suber plantation in southern Portugal. Continuous measurements were conducted between May 2003 and August 2004, while discontinuous measurements were conducted on a monthly basis between May and September 2003 and repeated between March and September 2004. Intensive measurements were conducted on ﬁve trees with mean height and DBH of 5.3 m and 11.6 cm, respectively, growing at close proximity to each other. Weather conditions and soil water potential (Ys) at the rhizosphere of each of the trees measured at 0.3 and 1 m soil depth were continuously monitored. Predawn (Ypd) and midday (Ymd) leaf water potentials were determined every month. Soil and plant samples were also collected in June and September from diﬀerent locations within the study site for d 18 O isotope composition analysis. Pressure–volume (p–v) curves were constructed from plant shoots at diﬀerent times during the vegetative period to determine osmotic potential at full saturation (P 100 ), water potential at turgor loss point (Ytlp), relative water content at turgor loss point (R*tlp) and bulk modulus of elasticity (e). Signiﬁcant P &lt; 0.05 decline in Ys occurred between May and September, the lowest value recorded being –2.0 MPa. Decline in soil moisture aﬀected tree water status, but decline in leaf water potential varied signiﬁcantly (P &lt; 0.05) among the trees. At the end of summer drought, lowest Ypd measured was –1.7 MPa while the highest measured during this time was –0.8 MPa. Diﬀerences among trees were attributed to diﬀerences in rooting depth, as shown by regression analysis of 18 O isotopes. Radial stem growth ceased when Ys within the upper 0.3 m depth approached –1.5 MPa. The upper soil layers contributed approximately 33% of the total tree water requirement, between spring and mid summer when drought was experienced by trees. Deep soil layers however, supplied most of the water required during drought and no growth was recorded during this time. Stressed trees increased solute concentration of their tissues by a Magnitude of 0.7 MPa while bulk tissue elastic modulus increased by about 17 MPa. The study emphasizes the signiﬁcance of roots as determinants of tree productivity and survival in the Mediterranean ecosystems.</style></abstract><issue><style face="normal" font="default" size="100%">1-2</style></issue></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%">Aranda, I.</style></author><author><style face="normal" font="default" size="100%">Castro, L.</style></author><author><style face="normal" font="default" size="100%">Pardos, M.</style></author><author><style face="normal" font="default" size="100%">Gil, L.</style></author><author><style face="normal" font="default" size="100%">Pardos, J. a</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Effects of the interaction between drought and shade on water relations, gas exchange and morphological traits in cork oak (Quercus suber L.) seedlings</style></title><secondary-title><style face="normal" font="default" size="100%">Forest Ecology and Management</style></secondary-title></titles><keywords><keyword><style  face="normal" font="default" size="100%">Cork oak</style></keyword><keyword><style  face="normal" font="default" size="100%">Drought</style></keyword><keyword><style  face="normal" font="default" size="100%">light</style></keyword><keyword><style  face="normal" font="default" size="100%">osmotic adjustment</style></keyword><keyword><style  face="normal" font="default" size="100%">photosynthesis</style></keyword><keyword><style  face="normal" font="default" size="100%">water use efficiency</style></keyword></keywords><dates><year><style  face="normal" font="default" size="100%">2005</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2005///</style></date></pub-dates></dates><urls><web-urls><url><style face="normal" font="default" size="100%">http://linkinghub.elsevier.com/retrieve/pii/S037811270500085X</style></url></web-urls></urls><volume><style face="normal" font="default" size="100%">210</style></volume><pages><style face="normal" font="default" size="100%">117 - 129</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">The combined effect of drought and light on different physiological and biochemical traits was assessed in cork oak (Quercus suber L.) seedlings grown under two levels of light availability and submitted to a long-standing drought. Watering was withdrawn after germination and seedlings were allowed to dry to a water content of ca. 50% of ﬁeld capacity. At this point, water-stressed seedlings were grown under moderate drought and two light regimes: high light (HL—50%) and low light (LL— 2%). Soil water in control plants was kept close to ﬁeld capacity (90–100%) for both light environments. Water-relations parameters derived from P–V curves, gas exchange and water status at predawn (Cpd ) were evaluated at twice during the experiment. Nitrogen and chlorophyll contents were determined in the same leaves used for the gas exchange measurements. In addition, maximum rate of carboxylation (Vcmax) and electronic transport (Jmax) were derived from A–Ci curves in well-watered seedlings. The variation on moisture availability during the experiment was the same under both light environments. In control plants, Cpd was over 0.3 MPa at the two harvests, while stressed seedlings decreased to 0.9 MPa, with no differences between light treatments. Water stress decreased osmotic potentials at full (Cp100 ) and zero turgor (Cp0 ). The regressions between both potentials and Cpd showed a higher intercept in shade grown seedlings. This fact will point out the higher osmoregulation capacity in sun seedlings whatever water availability. Nitrogen investment on a per leaf mass (Nmass ), chlorophyll content (Chlmass ) and SLA tended to show a typical pattern of sun-shade acclimation. Thus, the three parameters increased with shade. Only for Nmass there was a signiﬁcant effect of watering, since water stress increased Nmass . LL plants showed a lower photosynthetic capacity in terms of maximum net photosynthesis at saturating light (Amax), which was related to a decrease in Vcmax and Jmax . Both parameters varied with speciﬁc leaf area (SLA) in a similar way. The low-light environment brought about a higher nitrogen investment in chlorophyll, while under high-light environment the investment was higher in carboxylation (Vcmax) and electronic transport ( Fmax). Stomatal conductance to water vapour (gwv ) and Amax were lower in low-light seedlings independently of watering. In addition, there was a trend to keep higher intrinsic water use efﬁciency (IWUE) under high light environment. The increase of IWUE under water stress was higher in HL seedlings. This was as consequence of the steeper decline in gwv as Cpd decreased. The decrease of Amax with Cpd occurred in a similar way in LL and HL seedlings. Thus, the HL seedlings tended to sustain a higher ability to increase IWUE than LL seedlings when they were submitted to the same water stress.</style></abstract><issue><style face="normal" font="default" size="100%">1-3</style></issue></record><record><source-app name="Biblio" version="7.x">Drupal-Biblio</source-app><ref-type>47</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Castro, L.</style></author><author><style face="normal" font="default" size="100%">Aranda, I.</style></author><author><style face="normal" font="default" size="100%">Gil, L.</style></author><author><style face="normal" font="default" size="100%">Pardos, J. A.</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Relaciones hídricas en procedencias de QUERCUS SUBER L.</style></title><secondary-title><style face="normal" font="default" size="100%">III Congreso Forestal Español Congreso</style></secondary-title></titles><keywords><keyword><style  face="normal" font="default" size="100%">Cork oak</style></keyword><keyword><style  face="normal" font="default" size="100%">osmotic adjustment</style></keyword><keyword><style  face="normal" font="default" size="100%">pressure-volume curves</style></keyword><keyword><style  face="normal" font="default" size="100%">water potential</style></keyword></keywords><dates><year><style  face="normal" font="default" size="100%">2001</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2001///</style></date></pub-dates></dates><pages><style face="normal" font="default" size="100%">0 - 5</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Response to drought was studied in 5 provenances of cork oak, which are representative of the ecogeographic range of the species. The variation of several water parameters was analysed in 2000 from the beginning of the summer to the first rainy period. Predawn water potential (ψama) was measured on 5 dates on 6 plants per provenance. On the same plants, pressure-volume curves were carried out on twigs from the spring flushing. Several parameters related to responses to drought were estimated: osmotic potential at full turgor (ψπ 100) and at the loss turgor point (ψπ 0), relative water content at zero turgor (CHR0) and elastic modulus at maximum turgor (εmax). Afterwards osmotic and elastic adjustments were evaluated, and the response to drought was separated of the influence of other factor such as phenology. When the water parameters were analysed, there were not significant differences among provenances, meanwhile the differences among dates were highly significant. A decrease in ψπ 100 and an increase of tissue rigidity (εmax) were observed during the period of water stress. The response to drought overlapped with variations due to ontogenic factors.</style></abstract><notes><style face="normal" font="default" size="100%">The following values have no corresponding Zotero field:&lt;br/&gt;periodical: III Congreso Forestal Español Congreso</style></notes></record></records></xml>