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	Provedor de dados R.C. Suelo Nutr. Veg. (2) Ciencia e Investigación Agraria (1) Autor Cartes,Paula (3) Demanet,Rolando (2) Mora,María de la Luz (2) Alberdi,Miren (1) Jara,Alejandra A (1) Núñez,Pedro (1) Reyes-Díaz,Marjorie (1) Ribera-Fonseca,Alejandra (1) Salazar,Mauricio (1) Yañez-Mansilla,Erwin (1) Mais... Palavra-chave Nitrogen (2) Ammonium (1) Andisols (1) Leaching (1) N mineralization (1) Nitrate (1) Oxidative damage (1) Pasture (1) Phenolic compounds (1) Superoxide dismutase (1) Urea (1) Urease activity (1) Vaccinium corymbosum (1) Mais... Tipo do documento Journal article (3) Ano 2014 (1) 2009 (1) 2007 (1) País Chile (3) Idioma Inglês (3)		Ordenar por:  Relevância Autor Título Ano Registros recuperados: 3 Primeira ... 1 ... Última MOVEMENT OF N0(3)-N AND NH4-N IN AN ANDISOL AND ITS INFLUENCE ON RYEGRASS PRODUCTION IN A SHORT TERM STUDY R.C. Suelo Nutr. Veg. Mora,María de la Luz; Cartes,Paula; Núñez,Pedro; Salazar,Mauricio; Demanet,Rolando. In acids soils, the use of ammonium fertilizers accelerates the acidification processes and decreases both the production and persistence of the pastures. Nitrogen (N) is the most limiting factor for plant growth in most agricultural systems, but also it is one of the major environmental issues worldwide. In Chile, neither systematic studies in the first period of pasture growth and nor N leaching losses associated have been reported. The aims of this study were: (i) to evaluate the effect of the N sources at increasing rates of application on the yield and quality of ryegrass (Lolium perenne) and (ii) to quantify in the short-term the N potential leaching losses and the pH changes throughout the soil profile under field conditions. A field experiment was... Tipo: Journal article Palavras-chave: Ammonium; Leaching; Nitrate; Nitrogen; Pasture. Ano: 2007 URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-27912007000200005 UREASE ACTIVITY AND NITROGEN MINERALIZATION KINETICS AS AFFECTED BY TEMPERATURE AND UREA INPUT RATE IN SOUTHERN CHILEAN ANDISOLS R.C. Suelo Nutr. Veg. Cartes,Paula; Jara,Alejandra A; Demanet,Rolando; Mora,María de la Luz. Incubation studies were carried out to evaluate the effect of temperature and urea supply level on both the urease activity and the kinetics of N mineralization in two Andisols of Southern Chile. Our results showed that urease activity was higher in Piedras Negras soil (PNS) than Freiré soil (FS) at 24 and 48 h, and the enzyme was activated when the temperature increased from 5 to 21 °C. Urease activity followed a simple Michaelis-Menten kinetics. In PNS, the Michaelis Menten constant (Km) decreased, whereas the maximum enzyme reaction velocity (Vmax) and the catalytic efficiency increased when the temperature was raised up to 21 °C at 24 and 48 h of soil incubation. In FS, urease activity was the highest at 24 h, and it decreased at 48 h as a consequence... Tipo: Journal article Palavras-chave: Urease activity; N mineralization; Urea; Andisols. Ano: 2009 URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-27912009000100006 Photosynthetic and antioxidant performance are differentially affected by short-term nitrogen supply in highbush blueberry cultivars Ciencia e Investigación Agraria Yañez-Mansilla,Erwin; Cartes,Paula; Reyes-Díaz,Marjorie; Ribera-Fonseca,Alejandra; Alberdi,Miren. Nitrogen (N) is an essential nutrient for photosynthesis and may influence phenolic compound synthesis in higher plants. The effect of different amounts of N (0 to 38 mM) provided on a short-term (4 d) basis on the photosynthetic and antioxidant performance of highbush blueberry cultivars (Legacy and Bluegold) grown in a nutrient solution was studied. In both cultivars, the N concentration of leaves slightly increased in response to the N supply, with Bluegold frequently showing higher N concentrations than Legacy. Photosynthesis was reduced in Bluegold at the highest N dose, whereas in Legacy, a decrease of CO2 assimilation occurred under N starvation. This decrease in photosynthesis was accompanied by enhanced lipid peroxidation but only in Bluegold. In... Tipo: Journal article Palavras-chave: Nitrogen; Oxidative damage; Phenolic compounds; Superoxide dismutase; Vaccinium corymbosum. Ano: 2014 URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-16202014000100006 Registros recuperados: 3 Primeira ... 1 ... Última

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