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Transcriptional regulation of the rice arginine decarboxylase (Adc1) and S-adenosylmethionine decarboxylase (Samdc) genes by methyl jasmonate

  • Peremartí, Ariadna
  • Bassie Rene, Ludovic
  • Yuan, Dawei
  • Pelacho Aja, Ana Mª
  • Christou, Paul
  • Capell Capell, Teresa
We investigated the effect of methyl jasmonate (MeJa) treatment on the expression of two genes in the rice polyamine biosynthesis pathway and on the polyamine content in wild type plants and transgenic rice plants expressing a Datura stramonium (Ds) Adc cDNA, the latter accumulating up to three-fold the normal level of putrescine. Exogenous MeJa transiently inhibited the expression of OsAdc1, OsSamdc and Spermidine synthase (OsSpds) genes in the polyamine biosynthesis pathway, probably through transcriptional repression. There was also a similar negative impact on the DsAdc transgene in transgenic plants, even though a constitutive promoter was used to drive transgene expression. The free putrescine content was reduced significantly in the leaves of both wild type and transgenic plants in response to MeJa, although the magnitude of the effect was greater in wild type plants. We discuss our findings with respect to the previously proposed threshold model of polyamine metabolism in plants subjected to abiotic stress.
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Soil CO2 fluxes following tillage and rainfall events in a semiarid Mediterranean agroecosystem: Effects of tillage systems and nitrogen fertilization

  • Morell Soler, Francisco Joaquín
  • Álvaro-Fuentes, Jorge
  • Lampurlanés Castel, Jorge
  • Cantero-Martínez, Carlos
The response of soil CO2 flux to tillage operations and rainfall events was studied under semiarid Mediterranean conditions. The study was conducted on a barley monoculture agro-ecosystem during summer/autumn fallow periods in four consecutive years (2005–2008). The study compared three N fertilization levels (zero, medium; 60 kgNha−1; high, 120 kgNha−1) under three tillage systems (NT, no-tillage; MT, minimum tillage; CT, conventional tillage). Tillage operations led to a pulse of soil CO2 flux. This pulse was linearly related to soil CO2 flux on the day before tillage operations under MT (slope = 4.22) and CT (slope = 16.7), indicating the extent of soil disturbances. However, the associated soil CO2-C losses during tillage operations were reduced and similar among different tillage systems. The soil CO2 flux after rainfall was higher under NT, where it was linearly related to soil temperatures (0.15×soil temperature–1.06). Soil CO2 fluxes decreased on the following days as the soil dried. N fertilization affected CO2 flux in 5 out of 35 observation days, with higher fluxes with N fertilization under conservation tillage systems. Emissions after rainfall events led to large soil CO2-C losses, and these were of higher magnitude under conservation tillage systems (NT and MT).
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Studies on the interaction between grape-associated filamentous fungi on a synthetic medium

  • Valero Rello, Ana
  • Sanchís Almenar, Vicente
  • Ramos Girona, Antonio J.
  • Marín Sillué, Sònia
Eleven fungi isolated from grapes and sun-dried grapes (Alternaria alternata, Cladosporium herbarum, Eurotium amstelodami, Penicillium janthinellum, P. decumbens, Trichoderma harzianum, Candida sp., Aspergillus carbonarius OTA-negative, A. carbonarius OTA-positive, A. niger var. niger. and A. japonicus var. aculeatus), were grown in SNM medium at different water activities (0.82–0.97) and temperature (20–40 °C) levels for 18 days. Pairs of one Aspergillus faced with one non-Aspergillus were grown at 0.87–0.97 aw and at 20 and 30 °C. In single cultures, daily radii were recorded. In paired cultures radii were recorded and each A. section Nigri isolate was given a dominance score. At high temperatures and low water activities, Penicillium isolates, E. amstelodami and A. niger var. niger showed higher growth rates, while T. harzianum only grew well at the highest water activity. In addition, A. section Nigri was dominant in most paired assays, being only surpassed by T. harzianum at 0.97 aw and 20 °C. Thus, prevalence of A. section Nigri in sun-dried grapes can be explained by its adaptation to environmental conditions of sun-drying, and by its capability to dominate other fungal species when coming into contact with them.
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Long-term yield and water use efficiency under various tillage systems in Mediterranean rainfed conditions

  • Cantero-Martínez, Carlos
  • Angás Pueyo, Pedro
  • Lampurlanés Castel, Jorge
Conservation tillage (CT) can be beneficial for soil, water and soil organic matter conservation in Mediterranean areas that are prone to soil erosion and where water availability for crops is the main factor for sustainability. CT is the best option to protect the soil from erosion, improve infiltration, reduce soil evaporation and so conserve rainwater to increase crop water use (WU) and also water use efficiency (WUE). While CT can play an important role in reaching the stability and sustainability of these agricultural systems, performance depends upon the choice and adoption of an appropriate soil management (tillage) system. In rainfed areas of the Ebro Valley, winter cereals are the main crop sown. This paper presents the results of 15 years of research in different soil and climatic conditions of the area of CT on water conservation, WU and WUE. Long-term experiments, comparing different tillage systems, were established in 1987, 1990 and 1992, at three locations in the Ebro Valley, chosen according to their degree of aridity (Selvanera, Agramunt and El Cano´s). Results reveal that CT was most effective in increasing yield under the driest conditions at Agramunt (10–15%), still effective with a smaller advantage under slightly wetter conditions at El Cano´s (5–10%) but ineffective at Selvanera, the wettest site. CT only increased WU in some years at Agramunt and never at the other two sites. The benefits of CT to both increased yield at Agramunt and El Cano´s were determined by improved WUE arising from changes in the pattern of WU before and after anthesis.
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Promoter diversity in multigene transformation

  • Peremartí, Ariadna
  • Twyman, Richard M.
  • Gómez Galera, Sonia
  • Naqvi, Shaista
  • Farré Martinez, Gemma
  • Sabalza Gallués, Maite
  • Miralpeix i Anglada, Bruna
  • Dashevskaya, Svetlana
  • Yuan, Dawei
  • Ramessar, Koreen
  • Christou, Paul
  • Zhu, Changfu
  • Bassie Rene, Ludovic
  • Capell Capell, Teresa
Multigene transformation (MGT) is becoming routine in plant biotechnology as researchers seek to generate more complex and ambitious phenotypes in transgenic plants. Every nuclear transgene requires its own promoter, so when coordinated expression is required, the introduction of multiple genes leads inevitably to two opposing strategies: different promoters may be used for each transgene, or the same promoter may be used over and over again. In the former case, there may be a shortage of different promoters with matching activities, but repetitious promoter use may in some cases have a negative impact on transgene stability and expression. Using illustrative case studies, we discuss promoter deployment strategies in transgenic plants that increase the likelihood of successful and stable multiple transgene expression.
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Progesterone supplementation during mid-gestation increases the risk of abortion in Neospora-infected dairy cows with high antibody titres

  • Bech Sàbat, Gregori
  • López Gatius, Fernando
  • Santolaria Blasco, Pilar
  • García Ispierto, Irina
  • Pabón, M.
  • Nogareda, Carmina
  • Yániz Pérez de Albéniz, Jesús
  • Almería, S.
Progesterone has been reported to reduce Th1 responses during pregnancy. Thus, given that an excessive Th1 response could lead to abortion in Neospora-infected dairy cows, we hypothesized a reduction in abortion risk following progesterone supplementation during the mid-gestation period in these animals. Seropositive animals were assigned on day 120 of gestation to a Control (n = 33) or Treatment (n = 34) group. Treatment consisted of progesterone supplementation by fitting a progesterone releasing intravaginal device containing 1.55 g of progesterone for 28 days. Mean Neospora caninum antibody titres tested by ELISA on days 40, 90 and 120 of gestation were used to classify the cows as showing high (30 units) or low (<30 units) titration. Abortion rate showed a significant increase (P < 0.01) in the Treatment group (35%) compared to the Control (9%). Using logistic regression procedures, there was a significant (P < 0.0001) interaction between progesterone treatment and antibody titration. Progesterone-treated cows with a high antibody titre showed a likelihood of abortion 14.3 times higher than those not treated, while in cows with low antibody titres, exogenous progesterone had not effect. Our results do not support our starting hypothesis and suggest that progesterone supplementation in cows with high N. caninum antibody titres increases the risk of abortion possibly by affecting cell-mediated immune responses.
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Soil carbon dioxide flux and organic carbon content: effects of tillage and nitrogen fertilization

  • Morell Soler, Francisco Joaquín
  • Cantero-Martínez, Carlos
  • Lampurlanés Castel, Jorge
  • Plaza Bonilla, Daniel
  • Álvaro-Fuentes, Jorge
Th e response of soil CO2 fl ux to long-term tillage practices (no-tillage, NT; minimum tillage, MT; conventional tillage, CT) and N fertilization level (zero; medium, 60 kg N ha–1; high, 120 kg N ha–1) was studied during three growing season in a rainfed Mediterranean agroecosystem. Soil CO2 fl ux was related to the crop growth, with the highest fl ux during spring (i.e., March–May). Tillage and N fertilization eff ects on soil CO2 fl ux during growing seasons depended on weather conditions: greater soil CO2 fl ux under MT and NT on dry years, greater under CT and MT on a wet year. Nitrogen fertilization aff ected soil CO2 fl ux during this wet growing season: fl ux with N fertilizer additions was higher than fl ux on the unfertilized plots. Th irteen years aft er establishment of the experiment, the soil organic carbon (SOC) stock under long-term NT was 3.9 Mg C ha–1 greater than under CT and 4.3 Mg C ha–1 greater than under MT. Th e SOC stocks with N fertilizer additions were 4 Mg C ha–1 greater than the stock on unfertilized plots. Th e increase of C inputs with N fertilization was more pronounced under NT than under MT or CT. For this reason the increased response of SOC stock to N fertilization is expected under NT in a longer period of time. Th e product between soil water content and soil temperature explained between 75 and 94% of the seasonal variability of soil CO2 fl ux. However, soil CO2 fl ux and SOC stock were hardly related.
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Effect of the flexibility and the anion in the structural and transport properties of ethyl-methyl-imidazolium ionic liquids

  • Rey Castro, Carlos
  • Tormo, A. L.
  • Vega, Lourdes F.
This work summarizes some results obtained through equilibrium molecular dynamic simulations regarding the structure and transport properties of several ionic liquids (ILs). The Green–Kubo relationships were employed to evaluate the cation/anion diffusion coefficients, electrical conductivity and shear viscosity at 400 K. The ILs investigated were 1-ethyl-3-methylimidazolium salts of Cl−, NO3 − and PF6 − using two different force fields for the cation: a rigid ion model of 1-ethyl-3-methylimidazolium, studied in a previous work [C. Rey-Castro, L.F. Vega, J. Phys. Chem. B 110 (2006) 14426–14435] and the flexible model of Urahata and Ribeiro [S.M. Urahata, M.C.C. Ribeiro, J. Chem. Phys. 120 (2004) 1855–1863]. Regarding the anions, the most evident difference between the local structures in the three ILs is the position of the first peak of the radial distribution function, reflecting the differences in anion sizes and shapes. The velocity autocorrelation functions are particularly sensitive to the relative weights of anion and cation, although the integrated self-diffusion coefficients do not show significant differences between the Cl−, NO3 − and PF6 − salts. The electric conductivity predicted by the rigid ion model of [emim]Cl is lower than the experimental value, whereas the model overestimates the viscosities. In contrast, the flexible model leads to diffusion rates and conductivities that are one order of magnitude higher at the same temperature. The shear viscosities obtained from simulations of the flexible model are in very good agreement with experimental data. The calculated conductivities are compared with values obtained from the diffusion coefficients through the Nernst–Einstein relation in order to determine the importance of cross-correlation among ions. The stress tensor and the distinct van Hove correlation functions indicate that the dynamics of the local structure of the fluid relaxes faster in the flexible model.
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Factors affecting the response to the specific treatment of several forms of clinical anestrus in high producing dairy cows

  • López Gatius, Fernando
  • Mirzaei, A.
  • Santolaria Blasco, Pilar
  • Bech Sàbat, Gregori
  • Nogareda, Carmina
  • García Ispierto, Irina
  • Hanzen, Ch.
  • Yániz Pérez de Albéniz, Jesús
This study was designed to examine estrous response rates to the therapeutic treatment of clinical anestrus in high producing dairy cows and to identify the factors that could affect these rates. Cows with silent ovulation (Subestrus group), cystic ovarian disease (Cyst group) or ovarian hypofunction (OH group) were given specific treatment for their disorder. Data were derived from 1764 treatments in cows producing a mean of 45.4 kg of milk upon treatment including: 889 subestrous cows, 367 cystic cows and 508 cows with ovarian hypofunction. Cows showing estrus following treatment exhibited a similar pregnancy rate to cows attaining natural estrus used as reference: 33% (337/1006) and 35% (626/1796), respectively. No significant differences in pregnancy rates were observed among the Subestrus, Cyst and OH groups (34% (196/571), 34% (44/130), 32% (97/305), respectively. Based on the odds ratio, an estrous response for all groups was less likely to occur in cows that had suffered previous anestrus, compared to cows that were anestrous for the first time, whereas the likelihood of an estrous response increased in cows treated after 90 days in milk. Our results indicate that previous anestrus and a late stage of lactation can have a negative and positive effect, respectively, on the estrous response to the specific treatment of clinical anestrus shown by high producing dairy cows. Treatment targeted at each type of clinical anestrus can render similar pregnancy rates to those shown by cows in natural estrus.
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21st century climate change threatens mountain flora unequally across Europe

  • Engler, Robin
  • Randin, Christophe F.
  • Thuiller, Wilfried
  • Dullinger, Stefan
  • Zimmermann, Niklaus E.
  • Araújo, Miguel B.
  • Pearman, Peter B.
  • Le Lay, Gwenaëlle
  • Piedallu, Christian
  • Albert, Cécile H.
  • Choler, Philippe
  • Coldea, Gheorghe
  • de Lamo, Xavier
  • Dirnböck, Thomas
  • Gégout, Jean-Claude
  • Gómez García, Daniel
  • Grytnes, John Arvid
  • Heegaard, Einar
  • Hoistad, Fride
  • Nogués Bravo, David
  • Normand, Signe
  • Puscas, Mihai
  • Sebastià, Ma. T.
  • Stanisci, Angela
  • Theurillat, Jean-Paul
  • Trivedi, Mandar R.
  • Vittoz, Pascal
  • Guisan, Antoine
Continental-scale assessments of 21st century global impacts of climate change on biodiversity have forecasted range contractions for many species. These coarse resolution studies are, however, of limited relevance for projecting risks to biodiversity in mountain systems, where pronounced microclimatic variation could allow species to persist locally, and are ill-suited for assessment of species-specific threat in particular regions. Here, we assess the impacts of climate change on 2632 plant species across all major European mountain ranges, using high-resolution (ca. 100m) species samples and data expressing four future climate scenarios. Projected habitat loss is greater for species distributed at higher elevations; depending on the climate scenario, we find 36–55% of alpine species, 31–51% of subalpine species and 19–46% of montane species lose more than 80% of their suitable habitat by 2070–2100. While our high-resolution analyses consistently indicate marked levels of threat to cold-adapted mountain florae across Europe, they also reveal unequal distribution of this threat across the various mountain ranges. Impacts on florae from regions projected to undergo increased warming accompanied by decreased precipitation, such as the Pyrenees and the Eastern Austrian Alps, will likely be greater than on florae in regions where the increase in temperature is less pronounced and rainfall increases concomitantly, such as in the Norwegian Scandes and the Scottish Highlands. This suggests that change in precipitation, not only warming, plays an important role in determining the potential impacts of climate change on vegetation.
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