Efecto de la fuente de nitrógeno en la distribución de asimilados y composición de savia en ajipa (Pachyrhizus ahipa (Wedd.) Parodi)

7 páginas, 4 figuras, 1 tabla y 17 referencias. Trabajo presentado en el VI Simposium Nacional - II Ibérico sobre nutrición mineral de las plantas, Sevilla, del 12 al 15 de Noviembre de 1996. Entidades colaboradoras Junta de Andalucía, Universidad de Sevilla, Consejo Superior de Investigaciones Científicas, Sociedad Española de Fisiología Vegetal, El Monte, Caja de Huelva y Sevilla y Gat Fertiliquidos. Editores Científicos: Rafael Sarmiento Solís, Eduardo O. Leidi Montes y Antonio Troncoso de Arce. (Instituto de Recursos Naturales y Agrobiología de Sevilla).[EN]:Ahipa (Pachyrhizus ahipa (Wedd.) Parodi) is a legume root crop of Andean origin which accumulates carbohydrates of industrial interest in its tuberous roots and rotenone in leaves and seeds. The aim of this work was the study of lhe effect of N source (nitrate vs symbiotic N2, fixation) on growth, assimilate partitioning and xylem sap composition. The treatments consisted in: (a) plants inoculated with an specific Rhizobium strain irrigated wilh a N free nutrient solution (T-N2); and (b) non inoculated plants irrigated with a nutrient solution contai ning 4 mM NO3K (T-NO3). Main differences in growth and assimilate allocation were observed between plants grown in different treatments: N2,-fixing plants showed an increased earliness and reduced tuberous root growth in comparison with NO3-fed plants . Dry matter allocation into leaves and shoots was higher in NO -fed plants lhan in N2-fixing plants. Nitrogen concentration in leaves, stems and roots was higher in N2-fixing plants than in NO3-fed plants. At early growth stages, main xylem sap nitrogenous solutes were amino acids and amides. At flowering, N2-fixing plants showed high concentratÍon ofureides (allantoin+allantoic acid) and the amino acid L-canavanine[ES]:La ajipa (PachyrhiZlls ahipa (Wedd) Parodi), leguminosa de origen andino, se caracteriza por la acumulación de hidratos de carbono de interés industrial en sus raíces tuberosas y la presencia de rotenona en hojas y semillas. En este trabajo hemos estudiado el efecto de la nutrición nitrogenada (fijación simbiótica de N2 ó N mineral) sobre el crecimiento, partición de asimilados y composición de savia de xilema. Los tratamientos consistieron en: (a) plantas inoculadas con una cepa especifica de Rhizobium spp. (T-N2) y (b) plantas no inoculadas (T-NO3). Las planta se cultivaron en perlita/vermiculit y se regaron con solución de Hewitt sin N (T-N2) o 4 mM NO3K (T-NO3). Se observaron importantes diferencias debidas a la fuente de N: las plantas T-N, presentaron una mayor precocidad en la floración y fructificación y un menor desarrollo de la raíz tuberosa en comparación con las plantas T-NO2. La acumulación de materia seca en hojas y tallos de las plantas también fue superior en las plantas T-NO3. La concentración de N en hojas, tallos y raices fue superior en la plantas T-N2. En estadios tempranos de crecimiento, los componentes principales de savia de xilema, en ambos tratamientos. eran aminoácidos y amidas. En floración, las plantas T-N2, presentaban altas concentraciones de ureidos (alantoina+ácido alantoico) y el principal aminoácido transportado era L-canavanina.Sección de Nutrición Mineral de la Sociedad Española de Fisiología Vegetal y Instituto de Recursos Naturales y Agrobiología de Sevilla, CSIC.Peer reviewe

A model for the future: Ecosystem services provided by the aquaculture activities of Veta la Palma

En prensa2,041

A model for the future: Ecosystem services provided by the aquaculture activities of Veta la Palma, Southern Spain

© 2015 Elsevier B.V. The lack of space and opportunity for development has been identified as key reasons behind the stagnation of the European aquaculture industry. With the historical loss and degradation of current European wetlands there is an opportunity for harnessing the commercial investment of the aquaculture industry in construction of dual purpose wetlands that incorporate both conservation and extensive aquaculture activities. These wetlands can be used to expand the area available to suitable aquaculture into ecologically sensitive areas, such as Natura 2000 sites. Veta la Palma (VLP) situated in the Doñana Natural Park (and a Natura 2000 site) is an example of such an aquaculture development and a possible model for future opportunities. In the current study some of the important ecosystem services that are provided by VLP are assessed. The provisioning services of VLP were the economic rationale for the investment and more than 820tonnesyr-1 of fish and shrimp is produced, through a mixture of semi-extensive and extensive aquaculture. The regulating services include nutrient absorption, and the flow of river water through VLP and high primary production results in the absorption of 377tonnes of dissolved inorganic nitrogen yr-1, and 516tonnes of Cyr-1. Supporting services include the provision of habitat for more than 94 bird and 21 fish species. The primary production that supports the birds, extensive and semi-extensive aquaculture production was also estimated to be 167,000tonnes, 50,000tonnes and 133,000tonnesyr-1, respectively. The losses to birds are substantial and these estimates indicate that almost half of the primary production supports the wetland birds which directly consume 249tonnes of fish and 2578tonnes of invertebrates per annum. However it is the ecological credentials of the farm that enable premium prices and hence ensure the economic viability of the farm. The study demonstrates the possibility of using aquaculture to mitigate the historical loss of wetlands, provide significant ecosystem services and contribute to achievement of the European environmental legislative goals, and furthers the opportunity for the expansion of aquaculture into sensitive but impacted habitats.Peer Reviewe

Multicenter Study of Method-Dependent Epidemiological Cutoff Values for Detection of Resistance in Candida spp. and Aspergillus spp. to Amphotericin B and Echinocandins for the Etest Agar Diffusion Method

BSTRACT Method-dependent Etest epidemiological cutoff values (ECVs) are not available for susceptibility testing of either Candida or Aspergillus species with amphotericin B or echinocandins. In addition, reference caspofungin MICs for Candida spp. are unreliable. Candida and Aspergillus species wild-type (WT) Etest MIC distributions (microorganisms in a species-drug combination with no detectable phenotypic resistance) were established for 4,341 Candida albicans, 113 C. dubliniensis, 1,683 C. glabrata species complex (SC), 709 C. krusei, 767 C. parapsilosis SC, 796 C. tropicalis, 1,637 Aspergillus fumigatus SC, 238 A. flavus SC, 321 A. niger SC, and 247 A. terreus SC isolates. Etest MICs from 15 laboratories (in Argentina, Europe, Mexico, South Africa, and the United States) were pooled to establish Etest ECVs. Anidulafungin, caspofungin, micafungin, and amphotericin B ECVs (in micrograms per milliliter) encompassing �97.5% of the statistically modeled population were 0.016, 0.5, 0.03, and 1 for C. albicans; 0.03, 1, 0.03, and 2 for C. glabrata SC; 0.06, 1, 0.25, and 4 for C. krusei; 8, 4, 2, and 2 forC. parapsilosis SC; and 0.03, 1, 0.12, and 2 for C. tropicalis. The amphotericin B ECV was 0.25 � g/ml for C. dubliniensis and 2, 8, 2, and 16 � g/ml for the complexes of A. fumigatus, A. flavus, A. niger, and A. terreus, respectively. While anidulafung in Etest ECVs classified 92% of the Candida fks mutants evaluated as non-WT, the performance was lower for caspofungin (75%) and micafungin (84%) cutoffs. Finally, although anidulafungin (as an echinocandin surrogate susceptibility marker) and amphotericin B ECVs should identify Candida and Aspergillus isolates with reduced susceptibility to these agents using the Etest, these ECVs will not categorize a fungal isolate as susceptible or resistant, as breakpoints do. KEYWORDS ECVs, Etest ECVs, Etest MICs Candida, Etest MICs Aspergillus, WT isolates, amphotericin B resistance, antifungal resistance, echinocandin resistance, non-WT, susceptibility marke

Metales pesados en composts de lombrices

7 páginas, 2 tablas, 7 referencias.-- Trabajo presentado al citado Congreso en el Área de Comunicaciones Técnicas.-- Celebrado del 20-23, marzo, 1985, Cádiz, España.El libro de Charles Darwin "The formation of vegetable mould through the action of worms with observations on their habits", publicado en 1881, representó en su época un pilar básico en el conocimiento de la participación de los organismos en la formación del suelo. Darwin definió la tierra vegetal aunque consideraba más apropiado el término tierra animal como las uniformes y finas partículas, de color oscuro, que cubren la superficie de los suelos, y que ha pasado muchas veces a través del intestino de lombrices.Peer reviewe

Chemical and physico-chemical characterization of vermicomposts and their humic acid fractions

Six earthworm-composted wastes (vermicomposts), orginating from animal manure, municipal solid refuse and sewage sludge, treated with Eisenia foetida or Lumbricus rubellus, were chemically characterized for their total organic carbon, ash, macronutrients, micronutrients and potentially toxic heavy metal contents. Humic acids were isolated from the vermicomposts and analysed for their major elemental, and some heavy metals, composition and for structural and functional properties by electron spin resonance, infrared and pyrolysis-mass spectrometry. Infrared and pyrolysis-mass spectra of vermicompost humic acids resemble those of typical grass lignin. The fact that humic acids are operationally defined in terms of acid-base solubility tends to consider lignins, degraded lignins or lignin-rich materials extracted from vermicomposts as humic acids.Peer reviewe

Chemical and physico-chemical characterization of vermicomposts and their humic acid fractions

Six earthworm-composted wastes (vermicomposts), orginating from animal manure, municipal solid refuse and sewage sludge, treated with Eisenia foetida or Lumbricus rubellus, were chemically characterized for their total organic carbon, ash, macronutrients, micronutrients and potentially toxic heavy metal contents. Humic acids were isolated from the vermicomposts and analysed for their major elemental, and some heavy metals, composition and for structural and functional properties by electron spin resonance, infrared and pyrolysis-mass spectrometry. Infrared and pyrolysis-mass spectra of vermicompost humic acids resemble those of typical grass lignin. The fact that humic acids are operationally defined in terms of acid-base solubility tends to consider lignins, degraded lignins or lignin-rich materials extracted from vermicomposts as humic acids.Peer reviewe