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13 Pags.- 1 Fig.- 4 Tabls. ; Nutrition is a relevant issue for winegrowers because it influences grapevine growth, berry composition, as well as must and wine quality. In this research, the following impacts on the nutritional status of cv. Tempranillo grapevines were evaluated: simulated 2100 expected CO2, temperature (T) and relative humidity (RH) conditions (FCC; 700 µmol CO2/mol air, 28/18°C day/night and 33/53% RH, day/night) vs. current CO2, T and RH conditions (Curr; 390 µmol CO2/mol air, 24/14°C and 45/65% RH); well-watered (WW) vs. future expected water deficit (WD); and three texturally different soils with different clay contents (41, 19 and 8%). FCC resulted in reduced concentrations in leaf blades of N and Ca at veraison and N and Zn at full maturity. WD resulted in higher leaf blade Na and Mn concentrations at veraison and maturity, respectively compared to WW. However, K concentrations in the leaves and must were higher for WW than WD. Higher concentrations of Ca and Mn were found in leaf blades of grapevines sampled at full maturity from more clayey soils. Even when nutrient inputs exceeded plant extractions, high soil clay content increased the K concentration in must and consequently, could affect wine quality in terms of acidity loss. However, future expected water stress will have the opposite effect, reducing the berry K uptake under high soil clay (41%) conditions. ; We thank the Department of Economic Development and Competitiveness of the Basque Government and Aragón Government (A03 research group) for financial support. Urtzi Leibar was the recipient of a grant from "Fundación Cándido Iturriaga y María Doñabeitia". ; Peer reviewed

6 Pags., 6 figs. ; In this study, the effects of Fe resupply on the composition of the xylem sap and apoplastic fluid of Fe-deficient sugar beet plants were investigated. Experiments were carried out in growth chambers with plants grown in hydroponics, and Fe resupply to Fe-deficient plants was carried out by adding 45 μM Fe(III)–EDTA to the nutrient solution. In the short term (within 24 h), Fe resupply caused marked changes in the xylem sap and apoplastic fluid composition and in leaf physiological parameters when de novo chlorophyll (Chl) synthesis was still beginning. Major changes included: (i) 10- and 5-fold increases in Fe concentrations in apoplastic fluid and xylem sap, respectively; (ii) marked decreases in the concentrations of organic acids in apoplastic fluid, but not in xylem sap and (iii) large decreases in the citrate/Fe ratios, both in apoplastic fluid and in xylem sap. Two to four days after Fe resupply, xylem sap and apoplastic fluid Fe and organic acid concentrations and pH reached values similar to those obtained in Fe-sufficient leaves. Leaf mesophyll ferric chelate-reductase (FC-R) activities and photosynthetic rates increased gradually during recovery from Fe deficiency. ; This work was supported by the Spanish Ministry of Science and Innovation (MICINN) (projects AGL2006-1416 and AGL2007-61948, co-financed with FEDER), the Commission of European Communities (ISAFRUIT Project, Thematic Priority 5-Food Quality and Safety, of the 6th Framework Programme of RTD; Contract no. FP6-FOOD-CT-2006-016279) and the Aragón Government (Group A03). A.L. was supported by a pre-doctoral fellowship from the Spanish Institute of International Cooperation. ; Peer reviewed

8 Pags., 6 Figs. ; Greenhouse experiments were conducted to compare stress effects caused by Verticillium dahliae and drought on gas exchange, chlorophyll (Chl) fluorescence and photosynthetic pigments of pepper plants. Three treatments were compared: Verticillium inoculated plants (+V), non-inoculated well-watered plants (−V) and non-inoculated plants subjected to progressive drought (D). Gas exchange, fluorescence and photosynthetic pigments were measured and represented along a gradient of relative water content (RWC) and stomatal conductance (gs). Net photosynthesis (A) and electron transport rate (ETR) decreased, as RWC and gs declined, similarly in both +V and D plants. However, dark respiration (RD) and photorespiration (RL) tended to increase in inoculated plants compared to those subjected to soil drought, as gs decreased. Photoinhibitory damage was not observed in infected or in droughted plants. Soil drought decreased intrinsic PSII efficiency (Φexc.), which seemed to result in part from enhanced xanthophyll cycle- and/or lutein-related thermal energy dissipation. Nevertheless, the fact that 1−Φexc. increased in D only at high values of the de-epoxidation state of the xanthophyll cycle (DPS) suggests that ΔpH could be the major factor controlling thermal energy dissipation in this treatment. By contrast, antheraxanthin, zeaxanthin and lutein, as well as Φexc., were not markedly affected in +V. Water stress appeared to be the main limitation to photosynthesis in Verticillium infected plants, probably through stomatal closure, together with impaired mesophyll conductance (gm). However, our results indicate differential effects of V. dahliae on dark respiration, photorespiration, gm and on the capability of thermal energy dissipation under low gs values. ; This work was supported by NILSA (Navarra de Infraestructuras Locales S.A.), Aragón Government (A03 research group), Navarra Government and Asociación de Amigos de la Universidad de Navarra. ; Peer reviewed

Incluye material complementario ; The availability and management of N are major determinants of crop productivity, but N excessive use has an associated agro-ecosystems environmental impact. The aim of this work was to investigate the influence of N fertilization on yield and grain quality of 6 durum wheat genotypes, selected from 20 genotypes as high-and low-yielding genotypes. Two N levels were applied from anthesis to maturity: high (1/2 Hoagland nutrient solution) and low (modified 1/2 Hoagland with one-third of N). Together with the agronomic characterization, grain quality analyses were assessed to characterize carbohydrates concentration, mineral composition, glutenin and gliadin concentrations, polyphenol profile, and anti-radical activity. Nitrogen supply improved wheat grain yield with no effect on thousand-grain weight. Grain soluble sugars and gluten fractions were increased, but starch concentration was reduced, under high N. Mineral composition and polyphenol concentrations were also improved by N application. High-yielding genotypes had higher grain carbohydrates concentrations, while higher concentrations in grain minerals, gluten fractions, and polyphenols were recorded in the low-yielding ones. Decreasing the amount of N to one-third ensured a better N use efficiency but reduced durum wheat agronomic and quality traits. ; This research was supported by the Spanish MINECO project AGL2016-79868-R, AGL2015-63849-C2-1-R and CSIC (Intramural project). Sinda Ben Mariem had a PhD grant from Navarra Government.

Cereal yield and grain quality may be impaired by environmental factors associated with climate change. Major factors, including elevated CO2 concentration ([CO2]), elevated temperature, and drought stress, have been identified as affecting C3 crop production and quality. A me-ta‐analysis of existing literature was performed to study the impact of these three environmental factors on the yield and nutritional traits of C3 cereals. Elevated [CO2] stimulates grain production (through larger grain numbers) and starch accumulation but negatively affects nutritional traits such as protein and mineral content. In contrast to [CO2], increased temperature and drought cause significant grain yield loss, with stronger effects observed from the latter. Elevated temperature decreases grain yield by decreasing the thousand grain weight (TGW). Nutritional quality is also negatively influenced by the changing climate, which will impact human health. Similar to drought, heat stress decreases starch content but increases grain protein and mineral concentra-tions. Despite the positive effect of elevated [CO2], increases to grain yield seem to be counterbal-anced by heat and drought stress. Regarding grain nutritional value and within the three environmental factors, the increase in [CO2] is possibly the more detrimental to face because it will affect cereal quality independently of the region. ; This work was supported by European Interest Group (EIG) CONCERT-Japan (IRUEC), the Spanish Ministry of Science and Innovation (Spanish MINECO projects PCIN-2017-007 and PID2019-110445RB-I00). Sinda Ben Mariem had a PhD grant from the Navarra Government

18 Pags.- 6 Figs.- 2 Tabls. Copyright © 2020 Arrizabalaga-Arriazu, Gomès, Morales, Irigoyen, Pascual and Hilbert. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) and the copyright owner(s) are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms. ; Tempranillo is a grapevine (Vitis vinifera L.) variety extensively used for world wine production which is expected to be affected by environmental parameters modified by ongoing global climate changes, i.e., increases in average air temperature and rise of atmospheric CO2 levels. Apart from determining their effects on grape development and biochemical characteristics, this paper considers the intravarietal diversity of the cultivar Tempranillo as a tool to develop future adaptive strategies to face the impact of climate change on grapevine. Fruit-bearing cuttings of five clones (RJ43, CL306, T3, VN31, and 1084) were grown in temperature gradient greenhouses (TGGs), from fruit set to maturity, under two temperature regimes (ambient temperature vs. ambient temperature plus 4°C) and two CO2 levels (ambient, ca. 400 ppm, vs. elevated, 700 ppm). Treatments were applied separately or in combination. The analyses carried out included berry phenological development, the evolution in the concentration of must compounds (organic acids, sugars, and amino acids), and total skin anthocyanins. Elevated temperature hastened berry ripening, sugar accumulation, and malic acid breakdown, especially when combined with high CO2. Climate change conditions reduced the amino acid content 2 weeks after mid-veraison and seemed to delay amino acidic maturity. Elevated CO2 reduced the decoupling effect of temperature on the anthocyanin to sugar ratio. The impact of these factors, taken individually or combined, was dependent on the clone analyzed, thus indicating certain intravarietal variability in the response of Tempranillo to these climate change-related factors. ; This work was supported by the Ministerio de Economía y Competitividad of Spain (AGL2014-56075-C2-1-R), Fundación Universitaria de Navarra (2018), European Union (Erasmus+ grant to MA-A), Aquitaine Regional Council (AquiMOb grant to MA-A), and Asociación de Amigos de la Universidad de Navarra (doctoral grant to MA-A). This work also supported by the metaprogramme Adaptation of Agriculture and Forests to Climate Change (AAFCC) of the French National Institute for Agriculture, Food and Environment (INRAE), in the frame of LACCAVE2-21 project. ; Peer reviewed

The exploration of the grapevine (Vitis vinifera L.) intra-varietal diversity can be an interesting approach for the adaptation of viticulture to climate change. We evaluated the response of four Tempranillo clones to simulated year-2100-expected air temperature, CO2, and relative humidity (RH) conditions: climate change (CC; 28 °C/18 °C, 700 μmol mol-1 CO2, and 35%/53% RH) vs current situation conditions (CS; 24 °C/14 °C, 400 μmol mol-1 CO2, and 45%/63% RH), under two irrigation regimes, "well-watered"(WW) vs "water deficit"(WD). The treatments were applied to fruit-bearing cuttings grown under research-oriented greenhouse controlled conditions. CC increased sugar accumulation and hastened grape phenology, an effect that was mitigated by water deficit. Both CC and water deficit modified amino acid concentrations and accumulation profiles with different intensities, depending on the clone. Combined CC and water deficit decreased anthocyanins and the anthocyanin to total soluble solids (TSS) ratio. The results suggest differences in the response of the clones to the 2100-projected conditions, which are not always solely explained by differences observed in the ripening dynamics. Among the clones studied, RJ43 and CL306 were the most affected by CC/WD conditions; meanwhile, 1084 was globally less affected than the other clones. ; This work was supported by Ministerio de Economía y Competitividad of Spain (AGL2014-56075-C2-1-R), Fundación Universitaria de Navarra (2018), European Union (Erasmus+ grant to M.A.), Aquitaine Regional Council (AquiMob grant to M.A.), and Asociación de Amigos de la Universidad de Navarra (doctoral grant to M.A.). ; Peer reviewed

12 Pags.- 2 Tabls.- 6 Figs. © The Author(s) 2019. Published by Oxford University Press on behalf of the Society for Experimental Biology. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted reuse, distribution, and reproduction in any medium, provided the original work is properly cited. ; The activity of the protein kinase STN7, involved in phosphorylation of the light-harvesting complex II (LHCII) proteins, has been reported as being co-operatively regulated by the redox state of the plastoquinone pool and the ferredoxin–thioredoxin (Trx) system. The present study aims to investigate the role of plastid Trxs in STN7 regulation and their impact on photosynthesis. For this purpose, tobacco plants overexpressing Trx f or m from the plastid genome were characterized, demonstrating that only Trx m overexpression was associated with a complete loss of LHCII phosphorylation that did not correlate with decreased STN7 levels. The absence of phosphorylation in Trx m-overexpressing plants impeded migration of LHCII from PSII to PSI, with the concomitant loss of PSI–LHCII complex formation. Consequently, the thylakoid ultrastructure was altered, showing reduced grana stacking. Moreover, the electron transport rate was negatively affected, showing an impact on energy-demanding processes such as the Rubisco maximum carboxylation capacity and ribulose 1,5-bisphosphate regeneration rate values, which caused a strong depletion in net photosynthetic rates. Finally, tobacco plants overexpressing a Trx m mutant lacking the reactive redox site showed equivalent physiological performance to the wild type, indicating that the overexpressed Trx m deactivates STN7 in a redox-dependent way. ; This work was supported by the Spanish Ministry of Science and Innovation (AGL2016-79868) and from the Basque Government (UPV/EHU-GV IT-932-16). MA is a holder of a PhD fellowship from the Spanish Ministry of Education (FPU13/01675). ; Peer reviewed

34 Pags.- 3 Tabls.- 6 Figs. The definitive version is available at: http://www.sciencedirect.com/science/journal/01689452 ; This work aims to characterize the physiological response of grapevine (Vitis vinifera L.) cv. Tempranillo to UV-B radiation under water deficit conditions. Grapevine fruit-bearing cuttings were exposed to three levels of supplemental biologically effective UV-B radiation (0, 5.98 and 9.66 kJ m−2 day−1) and two water regimes (well watered and water deficit), in a factorial design, from fruit-set to maturity under glasshouse-controlled conditions. UV-B induced a transient decrease in net photosynthesis (Anet), actual and maximum potential efficiency of photosystem II, particularly on well watered plants. Methanol extractable UV-B absorbing compounds (MEUVAC) concentration and superoxide dismutase activity increased with UV-B. Water deficit effected decrease in Anet and stomatal conductance, and did not change non-photochemical quenching and the de-epoxidation state of xanthophylls, dark respiration and photorespiration being alternative ways to dissipate the excess of energy. Little interactive effects between UV-B and drought were detected on photosynthesis performance, where the impact of UV-B was overshadowed by the effects of water deficit. Grape berry ripening was strongly delayed when UV-B and water deficit were applied in combination. In summary, deficit irrigation did not modify the adaptive response of grapevine to UV-B, through the accumulation of MEUVAC. However, combined treatments caused additive effects on berry ripening. ; This work was supported by Fundación Universitaria de Navarra, Navarra-Aquitaine Cooperation Program (Gobierno de Navarra and Conseil Régional d'Aquitaine), Ministerio de Ciencia e Innovación of Spain (MCINN BFU2011-26989), European Union (FP7-KBBE-2012-6-singlestage), Asociación de Amigos de la Universidad de Navarra (grant to J. M-L), UV4growth COST Action FA0906 and Gobierno de Aragón (A03 research group). ; Peer reviewed

The total area under quinoa (Chenopodium quinoa Willd.) cultivation and the consumption of its grain have increased in recent years because of its nutritional properties and ability to grow under adverse conditions, such as drought. Climate change scenarios predict extended periods of drought and this has emphasized the need for new crops that are tolerant to these conditions. The main goal of this work was to evaluate crop yield and quality parameters and to characterize the physiology of two varieties of quinoa grown under water deficit in greenhouse conditions. Two varieties of quinoa from the Chilean coast (Rainbow) and altiplano (Illpa) were used, grown under full irrigation or two different levels of water deficit applied during the grain filling period. There were no marked differences in yield and quality parameters between treatments, but the root biomass was higher in plants grown under severe water deficit conditions compared to control. Photosynthesis, transpiration and stomatal conductance decreased with increased water stress in both cultivars, but the coastal variety showed higher water use efficiency and less discrimination of13 C under water deficit. This response was associated with greater root development and a better stomatal opening adjustment, especially in the case of Rainbow. The capacity of Rainbow to increase its osmoregulant content (compounds such as proline, glutamine, glutamate, K and Na) could enable a potential osmotic adjustment in this variety. Moreover, the lower stomatal opening and transpiration rates were also associated with higher leaf ABA concentration values detected in Rainbow. We found negative logarithmic relationships between stomatal conductance and leaf ABA concentration in both varieties, with significant R2 values of 0.50 and 0.22 in Rainbow and Illpa, respectively. These moderate-to-medium values suggest that, in addition to ABA signaling, other causes for stomatal closure in quinoa under drought such as hydraulic regulation may play a role. In conclusion, this work showed that two quinoa cultivars use different strategies in the face of water deficit stress, and these prevent decreases in grain yield and quality under drought conditions. ; This work was supported by the Government of Navarre (Rural Development, Environment and Local Administration unit)-FEADER (210160009).

16 Pag., 9 Fig., 5 Tabl. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CCBY). The .pdf document is protected by copyright and was first published by Frontiers. ; Crop Fe deficiency is a worldwide problem. The aim of this study was to assess the effects of foliar Fe applications in two species grown in different environments: peach (Prunus persica L. Batsch) trees grown in the field and sugar beet (Beta vulgaris L. cv. "Orbis") grown in hydroponics. The distal half of Fe-deficient, chlorotic leaves was treated with Fe sulfate by dipping and using a brush in peach trees and sugar beet plants, respectively. The re-greening of the distal (Fe-treated) and basal (untreated) leaf areas was monitored, and the nutrient and photosynthetic pigment composition of the two areas were also determined. Leaves were also studied using chlorophyll fluorescence imaging, low temperature-scanning electron microscopy microanalysis, scanning transmission ion microscopy-particle induced X-ray emission and Perls Fe staining. The distal, Fe-treated leaf parts of both species showed a significant increase in Fe concentrations (across the whole leaf volume) and marked re-greening, with significant increases in the concentrations of all photosynthetic pigments, as well as decreases in de-epoxidation of xanthophyll cycle carotenoids and increases in photochemical efficiency. In the basal, untreated leaf parts, Fe concentrations increased slightly, but little re-greening occurred. No changes in the concentrations of other nutrients were found. Foliar Fe fertilization was effective in re-greening treated leaf areas both in peach trees and sugar beet plants. Results indicate that the effects of foliar Fe-sulfate fertilization in Fe-deficient, chlorotic leaves were minor outside the leaf surface treated, indicating that Fe mobility within the leaf is a major constraint for full fertilizer effectiveness in crops where Fe-deficiency is established and leaf chlorosis occurs. ; Study supported by the Spanish Ministry of Science and Competitivity (MINECO; projects AGL2009-09018, AGL2010-16515, AGL2012-31988, and RTA-2010-00038-C03-01, co-financed with the European Regional Development Fund), the trilateral Project Hot Iron (ERA-NET Plant Genome Research KKBE; MINECO EUI2008-03618), the European Community as an Integrating Activity "Support of Public and Industrial Research Using Ion Beam Technology (SPIRIT)" under EC contract no.227012, and the Aragón Government(groupA03). Hamdi El-Jendoubi was supported by a FPI-MINECO grant. Ángeles Calatayud gratefully acknowledges the Conselleria de Agricultura, Pesca y Alimentación (Generalitat Valenciana) for her contract. ; Peer reviewed

Incluye material complementario ; Low atmospheric relative humidity (RH) accompanied by elevated air temperature and decreased precipitation are environmental challenges that wheat production will face in future decades. These changes to the atmosphere are causing increases in air vapor pressure deficit (VPD) and low soil water availability during certain periods of the wheat-growing season. The main objective of this study was to analyze the physiological, metabolic, and transcriptional response of carbon (C) and nitrogen (N) metabolism of wheat (Triticum durum cv. Sula) to increases in VPD and soil water stress conditions, either alone or in combination. Plants were first grown in well-watered conditions and near-ambient temperature and RH in temperature-gradient greenhouses until anthesis, and they were then subjected to two different water regimes well-watered (WW) and water-stressed (WS), i.e., watered at 50% of the control for one week, followed by two VPD levels (low, 1.01/0.36 KPa and high, 2.27/0.62 KPa; day/night) for five additional days. Both VPD and soil water content had an important impact on water status and the plant physiological apparatus. While high VPD and water stress-induced stomatal closure affected photosynthetic rates, in the case of plants watered at 50%, high VPD also caused a direct impairment of the RuBisCO large subunit, RuBisCO activase and the electron transport rate. Regarding N metabolism, the gene expression, nitrite reductase (NIR) and transport levels detected in young leaves, as well as determinations of the δ15N and amino acid profiles (arginine, leucine, tryptophan, aspartic acid, and serine) indicated activation of N metabolism and final transport of nitrate to leaves and photosynthesizing cells. On the other hand, under low VPD conditions, a positive effect was only observed on gene expression related to the final step of nitrate supply to photosynthesizing cells, whereas the amount of15N supplied to the roots that reached the leaves decreased. Such an effect would suggest an impaired N remobilization from other organs to young leaves under water stress conditions and low VPD. ; This work was supported by the Spanish Innovation and Universities Ministry (AGL2016-79868-R; 427 PCIN-2017-007) and the Basque Country Government consolidated group program (IT-932-16).

14 Pags.- 2 Tabls.- 5 Figs. his is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). ; In recent decades, mean global temperatures have increased in parallel with a sharp rise in atmospheric carbon dioxide (CO2) levels, with apparent implications for precipitation patterns. The aim of the present work is to assess the sensitivity of different phenological stages of grapevine to temperature and to study the influence of other factors related to climate change (water availability and CO2 concentration) on this relationship. Grapevine phenological records from 9 plantings between 42.75°N and 46.03°N consisting of dates for budburst, flowering and fruit maturity were used. In addition, we used phenological data collected from 2 years of experiments with grapevine fruit-bearing cuttings with two grapevine varieties under two levels of water availability, two temperature regimes and two levels of CO2. Dormancy breaking and flowering were strongly dependent on spring temperature, while neither variation in temperature during the chilling period nor precipitation significantly affected budburst date. The time needed to reach fruit maturity diminished with increasing temperature and decreasing precipitation. Experiments under semi-controlled conditions revealed great sensitivity of berry development to both temperature and CO2. Water availability had significant interactions with both temperature and CO2; however, in general, water deficit delayed maturity when combined with other factors. Sensitivities to temperature and CO2 varied widely, but higher sensitivities appeared in the coolest year, particularly for the late ripening variety, 'White Tempranillo'. The knowledge gained in whole plant physiology and multi stress approaches is crucial to predict the effects of climate change and to design mitigation and adaptation strategies allowing viticulture to cope with climate change. ; This work was funded by the Land Settlement Association, the University of Reading Research Endowment Trust and East Malling Trust, European Union (INNOVINE Call FP7-KBBE-2011-6, Proposal N°311775), Ministerio de Ciencia e Innovación of Spain (MCINN BFU 2011-26989), Ministerio de Economía y Competitividad of Spain (AGL2014-56075-C2-1-R), Aragón Government (A03 research group) and Asociación de Amigos de la Universidad de Navarra (grant to TK). ; Peer reviewed