Restrictive water condition modifies the root exudates composition during peanut-PGPR interaction and conditions early events, reversing the negative effects on plant growth

Water deficit is one of the most serious environmental factors that affect the productivity of crops in the world. Arachis hypogaea is a legume with a high nutritional value and 70% is cultivated in semi-arid regions. This research aimed to study the effect of water deficit on peanut root exudates composition, analyzing the importance of exudates on peanut-PGPR interaction under restrictive water condition.Peanut seedlings were subjected to six treatments: 0 and 15 mM PEG, in combination with non-inoculated, Bradyrhizobium sp. and Bradyrhizobium-Azospirillum brasilense inoculated treatments. We analyzed the 7-day peanut root exudate in response to a water restrictive condition and the presence of bacterial inocula. Molecular analysis was performed by HPLC, UPLC and GC. Bacteria motility, chemotaxis, bacterial adhesion to peanut roots and peanut growth parameters were analyzed. Restrictive water condition modified the pattern of molecules exuded by roots, increasing the exudation of Naringenin, oleic FA, citric and lactic acid, and stimulation the release of terpenes of known antioxidant and antimicrobial activity. The presence of microorganisms modified the composition of root exudates. Water deficit affected the first events of peanut-PGPR interaction and the root exudates favored bacterial mobility, the chemotaxis and attachment of bacteria to peanut roots.Changes in the profile of molecules exuded by roots allowed A. hypogaea-Bradyrhizobium and A.hypogaea?Bradyrhizobium-Azospirillum interaction thus reversing the negative effects of restrictive water condition on peanut growth. These findings have a future potential application to improve plant-PGPR interactions under water deficit by formulating inoculants containing key molecules exuded during stress.Fil: Cesari, Adriana Belen. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas Fisicoquímicas y Naturales. Instituto de Biotecnología Ambiental y Salud - Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Cordoba. Instituto de Biotecnología Ambiental y Salud; Argentina. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas Fisicoquímicas y Naturales. Departamento de Biología Molecular; ArgentinaFil: Paulucci, Natalia Soledad. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas Fisicoquímicas y Naturales. Instituto de Biotecnología Ambiental y Salud - Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Cordoba. Instituto de Biotecnología Ambiental y Salud; Argentina. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas Fisicoquímicas y Naturales. Departamento de Biología Molecular; ArgentinaFil: López Gómez, Miguel. Universidad de Granada; EspañaFil: Hidalgo Catellano, Javier. Universidad de Granada; EspañaFil: Luch Plá, Carmen. Universidad de Granada; EspañaFil: Dardanelli, Marta Susana. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas Fisicoquímicas y Naturales. Instituto de Biotecnología Ambiental y Salud - Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Cordoba. Instituto de Biotecnología Ambiental y Salud; Argentina. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas Fisicoquímicas y Naturales. Departamento de Biología Molecular; Argentin

One sixth of Amazonian tree diversity is dependent on river floodplains

Amazonia's floodplain system is the largest and most biodiverse on Earth. Although forests are crucial to the ecological integrity of floodplains, our understanding of their species composition and how this may differ from surrounding forest types is still far too limited, particularly as changing inundation regimes begin to reshape floodplain tree communities and the critical ecosystem functions they underpin. Here we address this gap by taking a spatially explicit look at Amazonia-wide patterns of tree-species turnover and ecological specialization of the region's floodplain forests. We show that the majority of Amazonian tree species can inhabit floodplains, and about a sixth of Amazonian tree diversity is ecologically specialized on floodplains. The degree of specialization in floodplain communities is driven by regional flood patterns, with the most compositionally differentiated floodplain forests located centrally within the fluvial network and contingent on the most extraordinary flood magnitudes regionally. Our results provide a spatially explicit view of ecological specialization of floodplain forest communities and expose the need for whole-basin hydrological integrity to protect the Amazon's tree diversity and its function.Naturali

Ampliación de la minicentral hidroeléctrica de Hervás (Cáceres)

A partir de esta memoria y de los anejos que la acompañan, se describen los aspectos relevantes del diseño de la posible ampliación de la minicentral hidroeléctrica situada en el municipio de Hervás (Cáceres). A continuación se presentan las características técnicas, económicas, ambientales y en materia de seguridad y salud de la obra proyectada y se complementa con el documento número 2 que contiene los planos con toda la información necesaria de la actuación, el documento número 3 que contiene el pliego de condiciones para la ejecución de la obra y el documento número 4 en el que se presenta el presupuesto de la obra.From this report and annexs which accompany it, describes the relevant aspects of the design of the possible expansion of the mini hydroelectric power plant located in the town of Hervás (Cáceres). Below are the technical, economic, environmental and health and safety of the work planned and is complemented with the document number 2 that contains planes with all the necessary information of the performance, the document number 3 that contains the terms and conditions for the execution of the work and the document number 4 which presents the budget of the work.Grado en Ingeniería Civil - Hidrología. Universidad de Exremadur

Caracterização de filmes de cds preparados pela técnica de deposição por laser pulsado (PLD)

Neste trabalho foi projetado e montado um sistema de evaporação de filmes finos utilizando um laser de Nd:YAG como a fonte de energia de evaporação com comprimentos de onda de 1064 nm e 532 nm. Esta técnica é conhecida como: Deposição com Laser Pulsado (Pulsed Laser Deposition, PLD). O material escolhido para evaporação foi o CdS. A caracterização dos filmes foi feita através de técnicas como difração de raios-X, microscopia eletrônica, transmissão, fotoluminescência, e absorção no infravermelho médio e distante por transformada de Fourier. Verificamos a obtenção de filmes cristalinos com estrutura wurtzita e com eixo c altamente orientado na direção perpendicular à superfície do substrato. Até onde conhecemos este é um resultado original para filmes evaporados com 532 nm. Através dos espectros de absorção e transmissão foram obtidos parâmetros importantes como espessura do filme, índice de refração, gap óptico e variação relativa da concentração de impurezas. Foi constatada uma diminuição na concentração de impurezas por excesso de Cd com o aumento da fluência e a diminuição do comprimento de onda de evaporação. O aumento da fluência também acarretou uma diminuição do gap do material como reflexo das variações na concentração de impurezas. As bandas de impurezas foram estudadas pela técnica de absorção no infravermelho médio e distante por transformada de Fourier. Os espectros de fotoluminescência obtidos mostraram picos de máxima intensidade no verde. Este aspecto é um indicador da alta qualidade dos filmes evaporado

Synthesis and structural studies of (3,5-dinitrobenzoate)bis(triphenylphosphine)copper(I)

The compound (3,5-dinitrobenzoate)bis(triphenylphosphine)copper(I) was synthesized and studied by IR spectroscopy and X-ray diffraction techniques. It is monomeric with the carboxylato acting as a monodentate ligand. The copper atom shows a trigonal planar coordination geometry. © 1993