Nuestros investigadores

Inmaculada Pascual Elizalde

Departamento
Biología Ambiental
Facultad de Ciencias. Universidad de Navarra
Líneas de investigación
Biología de la vid, Efectos del cambio climático en las plantas, Reutilización agrícola de residuos orgánicos, Estreses bióticos y abióticos en plantas
Índice H
15, (WoS, 26/09/2018)

Publicaciones científicas más recientes (desde 2010)

Autores: Pascual, I; Irigoyen, Juan José; et al.
Revista: AGRICULTURAL WATER MANAGEMENT
ISSN 0378-3774  Vol. 202  2018  págs. 299 - 310
In the Mediterranean area, changes in crop production and quality are expected in the future, due to one or more stress factors associated with climate change. Among them, plant responses to atmospheric CO2 concentration increases, enhanced temperatures and scarce water availability are a matter that deserves further investigation. In this study, the effects of the three above-mentioned factors, acting individually and/or in interaction, on grapevine reproductive growth and berry quality were investigated in three consecutive growing seasons (2013, 2014, and 2015) in the cultivars red and white Tempranillo. Eight different treatments were applied from fruit set to maturity (2 CO2 levels (400 versus 700 mu mol mol(-1)) x 2 temperature treatments (ambient versus ambient +4 degrees C) x 2 water availability regimes (well irrigated versus cyclic drought)) in four temperature gradient greenhouses located at the University of Navarra (Pamplona, Spain). Yield was significantly reduced by drought and was year-dependent. Eventual heat shocks (above 35 degrees C) in the first week of July in 2015 induced berry burn, browning and loss of 50% of the berries. Regarding quality, simulated climate change scenarios affected to greater extent technological (primary metabolism) than phenolic (secondary metabolism) maturity. Indeed, high temperature and drought significantly and consistently increased must pH, due to decreases in malic acid. On the contrary, elevated CO2 decreased pH associated with significant increases in tartaric acid. Differences in the response of red and white Tempranillo were found. Acidity was lower (and pH higher) in white than in red Tempranillo, due to lower malic and tartaric acid concentrations. Also, total polyphenol index was lower in the white variety, in part due to the absence of anthocyanins. Fresh bunch weight and berry water content were higher in the white than in the red variety. Interactions found among variety, year, water availability, temperature and CO2 have been highlighted and discussed. (C) 2017 Elsevier B.V. All rights reserved.
Autores: F.; Oyarzun, M.; et al.
Revista: PLANT SCIENCE
ISSN 0168-9452  Vol. 267  2018  págs. 74 - 83
The intra-varietal genetic diversity of grapevine (Vitis vinifera L.) may be exploited to maintain grape quality under future warm conditions, which may alter grape berry development and composition. The present study assesses the effects of elevated temperature on the development of berry, grape composition and anthocyanins:sugars ratio of thirteen clones of V. vinifera. cv. Tempranillo that differed in length of the ripening period (time from veraison to berry total soluble solids, mainly sugars, of ca. 22 °Brix). Two temperature regimes (24 °C/14 °C or 28 °C/18 °C, day/night) were imposed to grapevine fruit-bearing cuttings from fruit set to maturity under greenhouse-controlled conditions. Elevated temperature hastened berry development, with a greater influence before the onset of ripening, and reduced anthocyanin concentration, colour intensity and titratable acidity. The clones significantly differed in the number of days that elapsed between fruit set and maturity. At the same concentration of total soluble solids, the anthocyanin concentration was lower at 28 °C/18 °C than 24 °C/14 °C, indicating a decoupling effect of elevated temperature during berry ripening. Thermal decoupling was explained by changes in the relative rate of response of anthocyanin and sugar build-up, rather than delayed onset of anthocyanin accumulation. Clones differed in the degree of thermal decoupling, but it was directly associated with differences neither in the length of their ripening ...
Autores: Irigoyen, Juan José; Pascual, I; et al.
Revista: AGRICULTURAL WATER MANAGEMENT
ISSN 0378-3774  Vol. 202  2018  págs. 220 - 230
In recent decades, agricultural production is being affected by a sharp increase in atmospheric CO2 concentration. Due to the greenhouse effect gases, crops are impacted by enhanced temperatures and concomitantly by increased scarce water availability. All arid and semiarid areas, including Mediterranean viticulture, must face these three climate change-related factors: atmospheric CO2 concentration and temperature increases, and scarce water for irrigation. Scarce water is a problem even in irrigated viticulture, as irrigation is becoming more and more restricted. Within this context, the aim of this work was to investigate grapevine (Vitis vinifera L. cv. red and white Tempranillo) vegetative and reproductive growth. Fruit-bearing cuttings were grown under elevated CO2 (around 700 micromol mol-1 or ppm, versus 400), high temperature (ambient temperature +4°C, versus ambient) and water deficit (cyclic drought, versus full irrigated) in temperature gradient greenhouses for three consecutive growing seasons (years 2013, 2014 and 2015). Climate change impacted markedly vegetative growth. Within the abovementioned factors, vegetative growth (total vegetative mass) was significantly reduced by drought (consistent the three years) and was associated to a low substrate water status and low leaf stomatal conductance. Elevated CO2 stimulated total vegetative mass, whereas leaf area was not affected. When plants were grown under elevated CO2, the largest increases were observed ...
Autores:  Aranjuelo, I.; Pascual, I; et al.
Revista: PHOTOSYNTHESIS RESEARCH
ISSN 0166-8595  Vol. 138  Nº 1  2018  págs. 115 - 128
Foreseen climate change is expected to impact on grape composition, both sugar and pigment content. We tested the hypothesis that interactions between main factors associated with climate change (elevated CO2, elevated temperature, and water deficit) decouple sugars and anthocyanins, and explored the possible involvement of vegetative area, photosynthesis, and grape C uploading on the decoupling. Tempranillo grapevine fruit-bearing cuttings were exposed to CO2 (700 vs. 400ppm), temperature (ambient vs. +4 degrees C), and irrigation levels (partial vs. full) in temperature-gradient greenhouses. In a search for mechanistic insights into the underlying processes, experiments 1 and 2 were designed to maximize photosynthesis and enlarge leaf area range among treatments, whereas plant growth was manipulated in order to deliberately down-regulate photosynthesis and control vegetative area in experiments 3 and 4. Towards this aim, treatments were applied either from fruit set to maturity with free vegetation and fully irrigated or at 5-8% of pot capacity (experiments 1 and 2), or from veraison to maturity with controlled vegetation and fully irrigated or at 40% of pot capacity (experiments 3 and 4). Modification of air C-13 isotopic composition under elevated CO2 enabled the further characterization of whole C fixation period and C partitioning to grapes. Increases of the grape sugars-to-anthocyanins ratio were highly and positively correlated with photosynthesis and grape C-13 labeling, but not with vegetative area. Evidence is presented for photosynthesis, from fruit set to veraison, and grape C uploading, from veraison to maturity, as key processes involved in the establishment and development, respectively, of the grape sugars to anthocyanins decoupling.
Autores: Leibar, U.; Pascual, I; Aizpurua, A.; et al.
Revista: JOURNAL OF SOIL SCIENCE AND PLANT NUTRITION
ISSN 0718-9508  Vol. 17  Nº 2  2017  págs. 385 - 397
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.
Autores: U.; Pascual, I; A.; et al.
Revista: JOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE
ISSN 0022-5142  Vol. 97  Nº 8  2017  págs. 2633 - 2640
BACKGROUND: The influence of global warming on grape quality is a great concern among grapegrowers and enologists. The effects of simulated year 2100 expected CO2, temperature and relative humidity (RH) conditions (FCC; 700 mu mol CO2 mol(-1) air, 28/18 degrees C day/night and 33/53% RH, day/night) versus the current situation (Curr; 390 mu mol CO2 mol(-1) air, 24/14 degrees C and 45/65% RH); well-irrigated versus expected future water deficit and three soils with different clay contents (41, 19 and 8%) on yield and berry quality of grapevine cv. Tempranillo were evaluated. RESULTS: FCC shortened the time between fruit set and veraison and between fruit set and maturity by up to 7 and 10 days, respectively. This faster maturity led to higher must pH and tonality and reduced malic and tartaric acid concentrations, total anthocyanin concentration and colour intensity. Water deficit delayed ripeness for up to 9 days and reduced vegetative growth andmalic acid concentration of grapes. However, this malic acid reduction did not occurwith the clayey soils. These soils induced the lowest root fresh weight and berries with lower total anthocyanin concentration. CONCLUSION: Among the adaptation techniques to cope with the described effects on fruit composition, soil selection should be considered with attention in addition to irrigation practices.
Autores: S.; et al.
Revista: AUSTRALIAN JOURNAL OF GRAPE AND WINE RESEARCH
ISSN 1322-7130  Vol. 22  Nº 1  2016  págs. 87 - 95
Background and Aims: Atmospheric carbon dioxide (CO2) levels and temperature are expected to increase in the next decades. In addition, changes in climate as well as the stratospheric ozone concentration may affect the exposure of viticultural regions to UV-B. The aim of the present study was to investigate the effect of combined elevated CO2 and increased temperature (+CO2/+T) regimes and UV-B radiation on anthocyanin and flavonol biosynthesis in grape berries. Methods and Results: Three UV-B doses [0, 5.98 and 9.66kJ/(m(2)d)] and two CO2-day/night temperature regimes (390 mol/mol CO2-24/14 degrees C and 700mol/mol CO2-28/18 degrees C) were imposed on Vitis vinifera cv. Tempranillo fruit-bearing cuttings from fruitset to maturity. Berry mass, composition and expression of selected genes were monitored. The time to reach veraison and maturity was reduced under +CO2/+T. Anthocyanin concentration under +CO2/+T was higher 2 weeks after veraison, but lower at maturity. Ultraviolet-B radiation slowed berry development and upregulated flavonol and anthocyanin biosynthesis. Conclusions:The effect of UV-B, which modulates the accumulation of sugars and upregulates anthocyanin biosynthesis, compensated the deleterious effect of elevated CO2 and increased temperature on berry anthocyanin concentration. Significance of the Study: Certain viticultural practices, such as leaf removal, that modify the exposure of grapes to UV-B and the leaf surface to fruit mass ratio, may alleviate ...
Autores: Antolín, María del Carmen; I.; Goicoechea, María Nieves; et al.
Revista: THEORETICAL AND EXPERIMENTAL PLANT PHYSIOLOGY
ISSN 2197-0025  Vol. 28  Nº 2  2016  págs. 171 - 191
This paper describes the use of fruit-bearing grapevine hardwood cuttings as a model system for grapevine research, translating some studies that are difficult to execute under field conditions in the vineyards to facilities under controlled conditions. This approach enables to simulate in greenhouses future climate conditions and to investigate putative responses of grapevine to climate change. An updated description of how to grow grapevine fruit-bearing cuttings is made, together with modifications to carry out studies of partial rootzone drying, regulated deficit irrigation studies and symbiosis with arbuscular mycorrhizal fungi. We summarize how extensive has been the use of fruit-bearing cuttings in grapevine research over the years, with special emphasis in those experiments that analyze the effects of factors related to climate change, such as elevated CO2, elevated temperature, water availability and UV-B radiation, on grapevine physiology, production and grape quality. A validation of the model is made, comparing results obtained with fruit-bearing cuttings with those obtained from vineyard-grown plants. We discuss some advantages of growing grapevines under elevated CO2 with an atmosphere depleted in C-13, using this stable isotope (C-13) and others (N-15, Fe-54 or Fe-57, etc.) as tracers for C, N and other nutrient metabolism studies.
Autores: Vucetic, V.; et al.
Revista: FRONTIERS IN ENVIRONMENTAL SCIENCE
ISSN 2296-665X  Vol. 4  2016  págs. 48
Autores: S.; et al.
Revista: PLANT SCIENCE
ISSN 0168-9452  Vol. 232  2015  págs. 13 - 22
This work aims to characterize the physiological response of grapevine (Vitis vinifera L.) cv. Tempranilloto UV-B radiation under water deficit conditions. Grapevine fruit-bearing cuttings were exposed tothree levels of supplemental biologically effective UV-B radiation (0, 5.98 and 9.66 kJ m¿2day¿1) andtwo water regimes (well watered and water deficit), in a factorial design, from fruit-set to maturityunder 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. Methanolextractable UV-B absorbing compounds (MEUVAC) concentration and superoxide dismutase activityincreased with UV-B. Water deficit effected decrease in Anetand stomatal conductance, and did notchange non-photochemical quenching and the de-epoxidation state of xanthophylls, dark respirationand photorespiration being alternative ways to dissipate the excess of energy. Little interactive effectsbetween UV-B and drought were detected on photosynthesis performance, where the impact of UV-Bwas overshadowed by the effects of water deficit. Grape berry ripening was strongly delayed when UV-Band water deficit were applied in combination. In summary, deficit irrigation did not modify the adaptiveresponse of grapevine to UV-B, through the accumulation of MEUVAC. However, combined treatmentscaused additive effects on berry ripening.
Autores: S.; et al.
Revista: PLANT SCIENCE
ISSN 0168-9452  Vol. 236  2015  págs. 168 - 176
The increase in grape berry ripening rates associated to climate change is a growing concern for wine makers as it rises the alcohol content of the wine. The present work studied the combined effects of elevated CO2, temperature and UV-B radiation on leaf physiology and berry ripening rates. Three doses of UV-B: 0, 5.98, 9.66 kJ m(-2) d(-1), and two CO2-temperature regimes: ambient CO2-24/14 degrees C (day/night) (current situation) and 700 ppm CO2-28/18 degrees C (climate change) were imposed to grapevine fruit-bearing cuttings from fruit set to maturity under greenhouse-controlled conditions. Photosynthetic performance was always higher under climate change conditions. High levels of UV-B radiation down regulated carbon fixation rates. A transient recovery took place at veraison, through the accumulation of flavonols and the increase of antioxidant enzyme activities. Interacting effects between UV-B and CO2-temperature regimes were observed for the lipid peroxidation, which suggests that UV-B may contribute to palliate the signs of oxidative damage induced under elevated CO2-temperature. Photosynthetic and ripening rates were correlated. Thereby, the hastening effect of climate change conditions on ripening, associated to higher rates of carbon fixation, was attenuated by UV-B radiation.
Autores: U.; A.; O.; et al.
Revista: PHOTOSYNTHESIS RESEARCH
ISSN 0166-8595  Vol. 124  Nº 2  2015  págs. 199 - 215
While photosynthetic responses to elevated CO2, elevated temperature, or water availability have previously been reported for grapevine as responses to single stress factors, reports on the combined effect of multiple stress factors are scarce. In the present work, we evaluated effects of simulated climate change [CC; 700 ppm CO2, 28/18 °C, and 33/53 % relative humidity (RH), day/night] versus current conditions (375 ppm CO2, 24/14 °C, and 45/65 % RH), water availability (well-irrigated vs. water deficit), and different types of soil textures (41, 19, and 8 % of soil clay contents) on grapevine (Vitis vinifera L. cv. Tempranillo) photosynthesis. Plants were grown using the fruit-bearing cutting model. CC increased the photosynthetic activity of grapevine plants grown under well-watered conditions, but such beneficial effects of elevated CO2, elevated temperature, and low RH were abolished by water deficit. Under water-deficit conditions, plants subjected to CC conditions had similar photosynthetic rates as those grown under current conditions, despite their higher sub-stomatal CO2 concentrations. As expected, water deficit reduced photosynthetic activity in association with inducing stomatal closure that prevents water loss. Evidence for photosynthetic downregulation under elevated CO2 was observed, with decreases in photosynthetic capacity and leaf N content and increases in the C/N ratio in plants subjected to CC conditions. Soil texture had no marked effects on photosynthesis and did not modify the photosynthetic response to CC and water-deficit conditions. However, in mature well-irrigated plants grown in the soils with the highest sand content, an important decrease in stomatal conductance was observed as well as a slight decrease in the utilization of absorbed light in photosynthetic electron transport (measured as photochemical quenching), possibly related to a low water-retention capacity of these soils even under well-watered conditions.
Autores: Aranjuelo, I.; Pascual, I; et al.
Revista: JOURNAL OF PLANT PHYSIOLOGY
ISSN 0176-1617  Vol. 174  2015  págs. 97 - 109
Although plant performance under elevated CO2 has been extensively studied in the past little is known about photosynthetic performance changing simultaneously CO2, water availability and temperature conditions. Moreover, despite of its relevancy in crop responsiveness to elevated CO2 conditions, plant level C balance is a topic that, comparatively, has received little attention. In order to test responsiveness of grapevine photosynthetic apparatus to predicted climate change conditions, grapevine (Vitis vinifera L. cv. Tempranillo) fruit-bearing cuttings were exposed to different CO2 (elevated, 700 ppm vs. ambient, ca. 400 ppm), temperature (ambient vs. elevated, ambient +4 degrees C) and irrigation levels (partial vs. full irrigation). Carbon balance was followed monitoring net photosynthesis (A(N), C gain), respiration (R-D) and photorespiration (R-L) (C losses). Modification of environment C-13 isotopic composition (delta C-13) under elevated CO2 (from -10.30 to -24.93%) enabled the further characterization of C partitioning into roots, cuttings, shoots, petioles, leaves, rachides and berries. Irrespective of irrigation level and temperature, exposure to elevated CO2 induced photosynthetic acclimation of plants. C/N imbalance reflected the inability of plants grown at 700 ppm CO2 to develop strong C sinks. Partitioning of labeled C to storage organs (main stem and roots) did not avoid accumulation of labeled photoassimilates in leaves, affecting negatively Rubisco carboxylation activity. The study also revealed that, after 20 days of treatment, no oxidative damage to chlorophylls or carotenoids was observed, suggesting a protective role of CO2 either at current or elevated temperatures against the adverse effect of water stress.
Autores: I.; et al.
Revista: AGRICULTURAL WATER MANAGEMENT
ISSN 0378-3774  Vol. 159  2015  págs. 155 - 164
In the Mediterranean area, climate change is associated with atmospheric CO2 concentration increases, enhanced temperatures and scarce water availability, limiting seriously crop yield and decreasing quality. The aim of this study was to investigate the effects of elevated CO2, elevated temperature and water deficit, acting individually and/or interacting, on vegetative and reproductive growth, substrate and plant water status, and must quality in fruit-bearing cuttings of two grapevine (Vitis vinifera L.) cultivars (red and white Tempranillo). In four temperature gradient greenhouses, eight treatments were applied, from fruit set to maturity: CO2 level (400 versus 700 ¿mol mol¿1), temperature (ambient versus ambient +4 °C), and water availability (full irrigation versus cyclic drought). Effects of climate change on grape yield and quality were cultivar dependent. Generally, red Tempranillo had more vegetative growth and grape yield than the white cultivar. Also, grape yield was less affected by the treatments than vegetative growth. Drought, especially under elevated temperature, drastically reduced vegetative growth, bunch fresh and dry weights in both cultivars. Interestingly, elevated CO2 attenuated these negative effects of drought. The effects of climatic factors on yield were not associated with a worse water status of the vegetative or reproductive organs. In red Tempranillo, the combination of elevated CO2, elevated temperature and drought reduced total polyphenol index (TPI), malic acid and increased color density, but did not modify anthocyanin concentration. In white Tempranillo, the combined action of the three factors associated with climate change modified only tartaric acid. In this latter cultivar, drought increased TPI under ambient temperature, regardless of CO2 level, when compared with full-irrigated plants. In conclusion, climate change-related factors (elevated CO2, elevated temperature and water deficit) individually (especially drought) and/or interacting affected to different extent red and white Tempranillo vegetative growth and yield. Drought combined with elevated temperatures reduced grapevine performance, and elevated CO2 mitigated such deleterious effect.
Autores: Pascual, I; Aguirreolea, Jone Miren; et al.
Revista: PLANT SCIENCE
ISSN 0168-9452  Vol. 226  2014  págs. 30 - 40
Human activities are increasing atmospheric CO2 concentration and temperature. Related to this global warming, periods of low water availability are also expected to increase. Thus, CO2 concentration, temperature and water availability are three of the main factors related to climate change that potentially may influence crops and ecosystems. In this report, we describe the use of growth chamber - greenhouses (GCG) and temperature gradient greenhouses (TGG) to simulate climate change scenarios and to investigate possible plant responses. In the GCG, CO2 concentration, temperature and water availability are set to act simultaneously, enabling comparison of a current situation with a future one. Other characteristics of the GCG are a relative large space of work, fine control of the relative humidity, plant fertirrigation and the possibility of light supplementation, within the photosynthetic active radiation (PAR) region and/or with ultraviolet-B (UV-B) light. In the TGG, the three above-mentioned factors can act independently or in interaction, enabling more mechanistic studies aimed to elucidate the limiting factor(s) responsible for a given plant response. Examples of experiments, including some aimed to study photosynthetic acclimation, a phenomenon that leads to decreased photosynthetic capacity under long-term exposures to elevated CO2, using GCG and TGG are reported.
Autores: S.; et al.
Revista: PLANT AND CELL PHYSIOLOGY
ISSN 0032-0781  Vol. 55  Nº 11  2014  págs. 1925 - 1936
UV-B radiation and water deficit may trigger flavonol and anthocyanin biosynthesis in plant tissues. In addition, previous research has showed strong qualitative effects on grape berry skin flavonol and anthocyanin profiles in response to UV-B and water deficit. The aim of this study is to identify the mechanisms leading to quantitative and qualitative changes in flavonol and anthocyanin profiles, in response to separate and combined UV-B and water deficit. Grapevines (Vitis vinifera L. cv. Tempranillo) were exposed to three levels of UV-B radiation (0, 5.98 and 9.66 kJm(-2) day(-1)) and subjected to two water regimes. A strong effect of UV-B on flavonol and anthocyanin biosynthesis was found, resulting in an increased anthocyanin concentration and a change in their profile. Concomitantly, two key biosynthetic genes (FLS1 and UFGT) were up-regulated by UV-B, leading to increased flavonol and anthocyanin skin concentration. Changes in flavonol and anthocyanin composition were explained to a large extend by transcript levels of F3'H, F3'5'H and OMT2. A significant interaction between UV-B and water deficit was found in the relative abundance of 3'4' and 3'4'5' substituted flavonols, but not in their anthocyanin homologues. The ratio between 3'4'5' and 3040 substituted flavonols was linearly related to the ratios of F3'5'H and FLS1 transcription, two steps up-regulated independently by water deficit and UV-B radiation, respectively. Our results indicate that changes in flavonol profiles in response to environmental conditions are not only a consequence of changes in the expression of flavonoid hydroxylases; but also the result of the competition of FLS, F3'5'H and F3'H enzymes for the same flavonol substrates.
Autores: N.; G.; et al.
Revista: PHYTOCHEMISTRY
ISSN 0031-9422  Vol. 102  2014  págs. 106 - 114
Grapevine cv. Tempranillo fruit-bearing cuttings were exposed to supplemental ultraviolet-B (UV-B) radiation under controlled conditions, in order to study its effect on grape traits, ripening, amino acids and flavonoid profile. The plants were exposed to two doses of UV-B biologically effective (5.98 and 9.66kJm(-2)d(-1)), applied either from fruit set to ripeness or from the onset of veraison to ripeness. A 0kJm(-2)d(-1) treatment was included as a control. UV-B did not significantly modify grape berry size, but increased the relative mass of berry skin. Time to reach ripeness was not affected by UV-B, which may explain the lack of changes in technological maturity. The concentration of must extractable anthocyanins, colour density and skin flavonols were enhanced by UV-B, especially in plants exposed from fruit set. The quantitative and qualitative profile of grape skin flavonols were modified by UV-B radiation. Monosubstituted flavonols relative abundance increased proportionally to the accumulated UV-B doses. Furthermore, trisubstituted forms, which where predominant in non-exposed berries, were less abundant as UV-B exposure increased. Although total free amino acid content remained unaffected by the treatments, the increased levels of gamma-aminobutyric acid (GABA), as well as the decrease in threonine, isoleucine, methionine, serine and glycine, revealed a potential influence of UV-B on the GABA-mediated signalling and amino acid metabolism. UV-B had an overall positive impact on grape berry composition.
Autores: Irigoyen, Juan José; Goicoechea, María Nieves; Antolín, María del Carmen; et al.
Revista: PLANT SCIENCE
ISSN 0168-9452  Vol. 226  2014  págs. 22 - 29
Continued emissions of CO2, derived from human activities, increase atmospheric CO2 concentration. The CO2 rise stimulates plant growth and affects yield quality. Effects of elevated CO2 on legume quality depend on interactions with N2-fixing bacteria and mycorrhizal fungi. Growth at elevated CO2 increases photosynthesis under short-term exposures in C3 species. Under long-term exposures, however, plants generally acclimate to elevated CO2 decreasing their photosynthetic capacity. An updated survey of the literature indicates that a key factor, perhaps the most important, that characteristically influences this phenomenon, its occurrence and extent, is the plant source-sink balance. In legumes, the ability of exchanging C for N at nodule level with the N2-fixing symbionts creates an extra C sink that avoids the occurrence of photosynthetic acclimation. Arbuscular mycorrhizal fungi colonizing roots may also result in increased C sink, preventing photosynthetic acclimation. Defoliation (Anthyllis vulneraria, simulated grazing) or shoot cutting (alfalfa, usual management as forage) largely increases root/shoot ratio. During re-growth at elevated CO2, new shoots growth and nodule respiration function as strong C sinks that counteracts photosynthetic acclimation. In the presence of some limiting factor, the legumes response to elevated CO2 is weakened showing photosynthetic acclimation. This survey has identified limiting factors that include an insufficient N supply from bacterial strains, nutrient-poor soils, low P supply, excess temperature affecting photosynthesis and/or nodule activity, a genetically determined low nodulation capacity, an inability of species or varieties to increase growth (and therefore C sink) at elevated CO2 and a plant phenological state or season when plant growth is stopped.
Autores: S.; et al.
Revista: PLANT SCIENCE
ISSN 0168-9452  Vol. 213  2013  págs. 114 - 122
The present study aimed at evaluating the short- and long-term effects of UV-B radiation on leaves of grapevine Vitis vinifera (cv. Tempranillo). Grapevine fruit-bearing cuttings were exposed to two doses of supplemental biologically effective UV-B radiation (UV-BBE) under glasshouse-controlled conditions: 5.98 and 9.66 kJ m(-2) d(-1). The treatments were applied either for 20 d (from mid-veraison to ripeness) or 75 d (from fruit set to ripeness). A 0 kJ m(-2) d(-1) UV-B treatment was included as control. The main effects of UV-B were observed after the short-term exposure (20 d) to 9.66 kJ m(-2) d(-1). Significant decreases in net photosynthesis, stomatal conductance, sub-stomatal CO2 concentration, the actual photosystem II (PSII) efficiency, total soluble proteins and de-epoxidation state of the VAZ cycle were observed, whereas the activities of several antioxidant enzymes increased significantly. UV-B did not markedly affect dark respiration, photorespiration, the maximum potential PSII efficiency (Fv/Fm), non-photochemical quenching (NPQ), as well as the intrinsic PSI! efficiency. However, after 75 d of exposure to 5.98 and 9.66 kJ m(-2) d(-1) UV-B most photosynthetic and biochemical variables were unaffected and there were no sign of oxidative damage in leaves. The results suggest a high long-term acclimation capacity of grapevine to high UV-B levels, associated with a high accumulation of UV-B absorbing compounds in leaves, whereas plants seemed to be tolerant to moderate doses of UV-B.
Autores: Baslam, Marouane; Pascual, I; et al.
Revista: Journal of Agricultural and Food Chemistry
ISSN 0021-8561  Vol. 59  Nº 20  2011  págs. 11129 - 11140
Autores: Azcona, Iñaki; Pascual, I; Aguirreolea, Jone Miren; et al.
Revista: JOURNAL OF PLANT NUTRITION AND SOIL SCIENCE
ISSN 1436-8730  Vol. 174  Nº 6  2011  págs. 916 - 924
A greenhouse experiment was conducted to evaluate the effects of humic substances extracted from composted sewage sludge on growth, phenological development, and photosynthetic activity of pepper (Capsicum annuum L. cv. Piquillo) plants. Humic substances derived from composted sludge (HSS) were compared with those derived from leonardite (HSL). Two doses of both humic substances were assayed (200 and 500 mg C [L substrate](-1)) and compared with a control (C). HSS showed higher nitrogen content and a higher percentage of aliphatic carbon, as well as a lower content of aromatic and phenolic carbon than HSL. HSS significantly increased plant dry-matter production (up to 560%), plant height (86%151%), and leaf area (436%-1397%) during the early stages of pepper development. Net photosynthesis and stomatal conductance increased in the treatments with HSS (up to 48% and 63%, respectively) at the vegetative stage. In addition, HSS accelerated the phenological development of pepper plants, reducing significantly the number of days to flowering and ripening, which occurred 12 and 14 d earlier than in control plants, respectively. In general, the treatments with HSS and HSL did not markedly affect chlorophyll and nutrient concentrations in the leaves. At maturity, only small differences in total fruit yield, number of fruits per plant, and fruit size were observed between amended and control plants. The results suggest that the mechanisms through which HSS affected plant growth and development were not associated with an improved nutrient uptake. Although the identity of the growth-promoting factors remains to be found, the results suggest that they may be linked to the chemical structure of the humic substances.
Autores: Pascual, I; Azcona, Iñaki; Aguirreolea, Jone Miren; et al.
Revista: Journal of Agricultural and Food Chemistry
ISSN 0021-8561  Vol. 58  Nº 11  2010  págs. 6951 - 6959
Autores: Pascual, I; Azcona, Iñaki; Aguirreolea, Jone Miren; et al.
Revista: J PLANT PHYSIOL
ISSN 0176-1617  Vol. 167  Nº 9  2010  págs. 701 - 708
Autores: Morales, F.; Pascual, I; et al.
Libro:  Current research in plant physiology. FV2015 Book of abstracts. Toledo, June 14-17, 2015
2015  págs. 210 - 211
Human activities are increasing atmospheric CO2 concentration and temperature. Related to this global warming, periods of low water availability are also expected to increase. Thus, CO2 concentration, temperature and water availability are three of the main factors related to climate change that potentially may influence crops and ecosystems. In this communication, we describe the use of growth chamber greenhouses (GCG) (a new concept of greenhouse for plant research) and temperature gradient greenhouses (TGG) (an improved version of the temperature gradient tunnel) to simulate climate change scenarios and to investigate possible plant responses (Morales et al., 2014). In the GCG, CO2 concentration, temperature and water availability are set to act simultaneously, enabling comparison of a current situation with a future one. Other characteristics of the GCG are a relative large space of work, fine control of the relative humidity, plant fertirrigation and the possibility of light supplementation, within the photosynthetic active radiation (PAR) region and/or with ultraviolet-B (UV-B) light. In the TGG, the three above-mentioned factors can act independently or in interaction, enabling more mechanistic studies aimed to elucidate the limiting factor(s) responsible for a given plant esponse. Examples of experiments, including some aimed to study photosynthetic acclimation, a phenomenon that leads to decreased photosynthetic capacity under long-term exposures to elevated CO2
Autores: Baslam, Marouane; Pascual, I; et al.
Libro:  Beneficial plant-microbial interactions: ecology and applications
2013  págs. 89 - 412

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