Cambra I.,Technical University of Madrid |
Martinez M.,Technical University of Madrid |
Dader B.,Institute Ciencias Agrarias CSIC |
Gonzalez-Melendi P.,Technical University of Madrid |
And 3 more authors.
Journal of Experimental Botany | Year: 2012
Among the C1A cysteine proteases, the plant cathepsin F-like group has been poorly studied. This paper describes the molecular and functional characterization of the HvPap-1 cathepsin F-like protein from barley. This peptidase is N-glycosylated and has to be processed to become active by its own propeptide being an important modulator of the peptidase activity. The expression pattern of its mRNA and protein suggest that it is involved in different proteolytic processes in the barley plant. HvPap-1 peptidase has been purified in Escherichia coli and the recombinant protein is able to degrade different substrates, including barley grain proteins (hordeins, albumins, and globulins) stored in the barley endosperm. It has been localized in protein bodies and vesicles of the embryo and it is induced in aleurones by gibberellin treatment. These three features support the implication of HvPap-1 in storage protein mobilization during grain germination. In addition, a complex regulation exerted by the barley cystatins, which are cysteine protease inhibitors, and by its own propeptide, is also described. © 2012 The Author(s).
Grillo O.,Stazione Consorziale Sperimentale di Granicoltura per la Sicilia |
Andres M.F.,Institute Ciencias Agrarias CSIC |
Moreno-Vazquez S.,Technical University of Madrid
Crop Protection | Year: 2016
Heterodera avenae and other cyst-producing nematode species are traditionally counted manually by visual inspection, a laborious and time consuming process. A method to detect and count cereal cyst nematodes based on image analysis techniques and statistical identification was designed and tested on H. avenae white females. Nematodes at the white female stage and free of soil particles were isolated from a contaminated wheat field. Known quantities of white females were mixed with different pre-treated background soil samples from non infested fields. Pre-treatment consisted of typical sieving and centrifugation procedures for white female extraction. Image analysis techniques were then used to detect, count and characterize white females in the mixtures. Over 96% of the H. avenae white females and substrate particles were correctly identified showing that a clear distinction can be drawn between the two groups. The results confirmed the validity of the proposed method to identify and count H. avenae females in backgrounds of different origins. This study establishes the basis for the design of a standardized method that is easily incorporated into a stand-alone system to facilitate the detection and quantification of nematode inoculum. This method can be applied to evaluate infestation level in crop fields and also to detect resistance/tolerance in breeding lines. © 2015 Elsevier Ltd.
Caballero R.,Institute Ciencias Agrarias CSIC
Open Agriculture Journal | Year: 2015
Large Scale Grazing Systems (LSGSs) in Europe are extensive systems of grassland management, which have developed from the interaction of historical background, human behaviour and natural resources, and are mainly located in the Less Favoured Areas (LFAs). LSGSs currently face competing threats towards intensification and/or abandonment but, at the same time, they harbour a significant part of European nature values. Socio-economic driving forces of land abandonment and intensification are poorly addressed. The current system assumes that these LSGSs are inherently uneconomic and only payments for the potential delivery of environmental services and side line activities are the source of continuity and justification of support. Our conceptual approach, however, is based on the assumptions that endogenous development and targeted policy schemes cannot be disregarded. A framework profile is provided for the identification and description of European LSGSs where regeneration plans can be more cost-effective. Under this conceptual approach, operational tools such as pastoral strategies for survival and system-specific management alternatives can be devised for interplay of environmental and socio-economic functions, facilitating interdisciplinary research within and across systems. From the empirical perspective, we show how the trend of abandonment of LSGS in the last 60 years is spread over different regions of Europe, how management alternatives are designed for six separate LSGS, and how beneficial management alternatives, environmental functions and side line activities cited by experts on an additional sample of 46 European LSGS are grouped by type of action. We conclude that the continuity of LSGSs in the European Union (EU) may require a new and sustainable intensification path with new farming models and farming categories as far removed from the conventional intensification path as from the low-input, nature reserve and generalised policy support paradigms. Beneficial management with key actions can be a sensible rationale for specific and dynamic support to LSGS in the next CAP reform post-2013, time of stressing budgetary conditions. © Rafael Caballero.
Wierzchos J.,CSIC - National Museum of Natural Sciences |
Davila A.F.,NASA |
Artieda O.,University of Extremadura |
Camara-Gallego B.,CSIC - National Museum of Natural Sciences |
And 5 more authors.
Icarus | Year: 2013
The hyper-arid core of the Atacama Desert in Chile is considered the driest and most life-limited place on Earth, with few habitats capable of sustaining an active microbial ecosystem. As such, it is one of the best terrestrial analogues of the extreme arid conditions on Mars, and an ideal environment to explore survival and biological adaptation strategies as the environment becomes increasingly dry. Here we show that weakly welded rhyolitic ignimbrites in this desert are abundantly colonized by endolithic cyanobacteria and associated heterotrophic bacteria. We propose that the porous ignimbrite interior provides protection from damaging UV radiation and excessive levels of visible light. Rock porosity also favors cell hydration through water retention after scarce rainfall events, even when the surrounding environment remains stubbornly dry. This is the first known example of an endolithic microbial community colonizing ignimbrite rocks in an extremely dry environment. The existence of a habitat capable of supporting abundant phototrophic and heterotrophic communities in an environment that precludes most life forms suggests that, if similar deposits are found on Mars, these should be considered important targets in the search for life. Indeed, ignimbrite rocks have been tentatively identified in Gale Crater, the landing site of the Mars Science Laboratory (MSL) mission and could be directly analyzed by its rover Curiosity. © 2012 Elsevier Inc.
Arauzo M.,Institute Ciencias Agrarias CSIC |
Valladolid M.,CSIC - National Museum of Natural Sciences
Agriculture, Ecosystems and Environment | Year: 2013
Alluvial areas are particularly vulnerable to drainage and N-leaching from agriculture, with a subsequent impact on the quality of alluvial aquifers.An analysis of the influence of the physical environment and soil usage on the vertical processes involved in nitrogen transport through the vadose zone of three different agricultural plots was conducted over 40 consecutive months. To achieve this, six monitoring stations were equipped with a Gee Passive Capillary Lysimeter, three FDR probes and a rain gauge and connected to a data-logger which recorded relevant data on an hourly basis throughout the experiment. The Gee Lysimeter is a relatively new device that allows the direct, continuous measurement of deep drainage in the field and also enables drainage water to be sampled for chemical analysis.The study area was located in the middle and lower sections of the Oja Alluvial Aquifer (Oja-Tirón catchment, Spain). This alluvial aquifer was selected because it constitutes a good example of a mass of water chronically affected by nitrate pollution from agricultural sources. In accordance with the requirements of the EU Nitrates Directive, a surface area of 94.3 km2 was declared a Nitrate Vulnerable Zone (NVZ), corresponding to 39% of the alluvial area of the Oja-Tirón catchment.A combination of factors associated with the physical substrate (soil texture, infiltration rate, field capacity) and the agricultural use (under conventional or ecological production systems) determined the final nitrogen leaching load from each plot. The plots located in the middle section of the aquifer (sites 1 and 2, with shallow, stony soils) generated more intensive drainage and higher N-leaching than the plot located in the lower section (Site 3, with a deep, fine textured soil), where there was no drainage, nor N-leaching. Paradoxically, the Site 3 plot was the only one found within the NVZ designated perimeter. It was also observed that when the degree of vulnerability associated with the textural characteristics of the substrate was high, drainage and N-leaching could be affected by the agricultural production model. These results support the proposal of Arauzo et al. (2011) to designate, as a general criterion, the entire alluvial area as a NVZ. © 2013 Elsevier B.V.