Variation of grain nitrogen content in relation with grain yield in old and modern Spanish wheats grown under a wide range of agronomic conditions in a Mediterranean region

Wheat yield and grain nitrogen concentration (GNC; mg N/g grain) are frequently negatively correlated. In most growing conditions, this is mainly due to a feedback process between GNC and the number of grains/m2. In Mediterranean conditions, breeders may have produced cultivars with conservative grain set. The present study aimed at clarifying the main physiological determinants of grain nitrogen accumulation (GNA) in Mediterranean wheat and to analyse how breeding has affected them. Five field experiments were carried out in north-eastern Spain in the 2005/06 and 2006/ 07 growing seasons with three cultivars released at different times and an advanced line. Depending on the experiment, source-sink ratios during grain filling were altered by reducing grain number/m2 either through pre-anthesis shading (unshaded control or 0.75 shading only between jointing and anthesis) or by directly trimming the spikes after anthesis and before the onset of the effective grain filling period (un-trimmed control or spikes halved 7–10 days after anthesis). Grain nitrogen content (GN content ; mg N/grain) decreased with the year of release of the genotypes. As the number of grains/m2 was also increased by breeding there was a clear dilution effect on the amount of nitrogen allocated to each grain. However, the increase in GN content in old genotypes did not compensate for the loss in grain nitrogen yield (GNY) due to the lower number of grains/m2. GN content of all genotypes increased (increases ranged from 0.13 to 0.40 mg N/grain, depending on experiment and genotype) in response to the post-anthesis spike trimming or pre-anthesis shading. The degree of source-limitation for GNA increased with the year of release of the genotypes (and thus with increases in grain number/m2) from 0.22 (mean of the four manipulative experiments) in the oldest cultivar to 0.51 (mean of the four manipulative experiments) in the most modern line. It was found that final GN content depended strongly on the source-sink ratio established at anthesis between the number of grains set and the amount of nitrogen absorbed at this stage. Thus, Mediterranean wheat breeding that improved yield through increases in grain number/m2 reduced the GN content by diluting a rather limited source of nitrogen into more grains. This dilution effect produced by breeding was further confirmed by the reversal effect produced by grain number/m2 reductions due to either pre-anthesis shading or post-anthesis spike trimming.

Sink limitations to yield in wheat : how could it be reduced?

Further genetic gains in wheat yield are required to match expected increases in demand. This may require the identification of physiological attributes able to produce such improvement, as well as the genetic bases controlling those traits in order to facilitate their manipulation. In the present paper, a theoretical framework of source and sink limitation to wheat yield is presented and the fine-tuning of crop development as an alternative for increasing yield potential is discussed. Following a top-down approach, most crop physiologists have agreed that the main attribute explaining past genetic gains in yield was harvest index (HI). By virtue of previous success, no further gains may be expected in HI and an alternative must be found. Using a bottom-up approach, the present paper firstly provides evidence on the generalized sink-limited condition of grain growth, determining that for further increases in yield potential, sink strength during grain filling has to be increased. The focus should be on further increasing grain number per m2, through fine-tuning pre-anthesis developmental patterns. The phase of rapid spike growth period (RSGP) is critical for grain number determination and increasing spike growth during pre-anthesis would result in an increased number of grains. This might be achieved by lengthening the duration of the phase (though without altering flowering time), as there is genotypic variation in the proportion of pre-anthesis time elapsed either before or after the onset of the stem elongation phase. Photoperiod sensitivity during RSGP could be then used as a genetic tool to further increase grain number, since slower development results in smoother floret development and more floret primordia achieve the fertile floret stage, able to produce a grain. Far less progress has been achieved on the genetic control of this attribute. None of the well-known major Ppd alleles seems to be consistently responsible for RSGP sensitivity. Alternatives for identifying the genetic factors responsible for this sensitivity (e.g. quantitative trait locus (QTL) identification in mapping populations) are being considered.

Sistema de monitorització Open Source: projecte d'empresa per Computer Technology Catalunya

L’objectiu del projecte consisteix en l’estudi, simulació i implantació d’un conjunt d’aplicacions que permeten tenir un control sobre possibles problemes que puguin succeir a la nostra xarxa. Aquest projecte és la solució als problemes de detecció d’errors en el funcionament de les infraestructures de networking de les que disposen els nostres clients.

Open source framework for trucks fleet control (client)

Aquest projecte desenvolupa la part client d'una aplicació per controlar una flota de camions. Està implementada per funcionar sobre un dispositiu mòbil que funcioni amb el sistema operatiu Android.

Gestió Documental Open Source per Agresso CRM

Estudi i integració d'una aplicació Open Source especialitzada en la gestió documental amb Agresso CRM. L'objectiu d'aquesta aplicació és oferir nova funcionalitat a la gestió documental inicial i augmentar-ne les seves capacitats. Per tal de dur-lo a terme s’ha fet una recerca i un estudi d'aplicacions Open Source especialitzades en la gestió documental. Entre les aplicacions estudiades s'ha escollit KnowledgeTree pel desenvolupament de la integració, ja que era la que responia d’una manera més satisfactòria als requisits.

Creació automàtica de gràfics estadístics a partir de dades de soroll d’Europa amb tecnologies Open Source en el visor Noise Map Viewer de l’ETC-LUSI

El projecte ha consistit en la creació de gràfics estadístics de soroll d’Europa de forma automàtica amb tecnologies Open Source dins el visor Noise Map Viewer per Europa de l’ETC-LUSI. La llibreria utilitzada per fer aquest procés ha estat JFreeChart i el llenguatge de programació utilitzat ha estat Java (programació orientada a objectes) dins l’entorn de desenvolupament integrat Eclipse. La base de dades utilitzada ha estat PostgreSQL. Com a servidors s’han fet servir Apache (servidor HTTP) i Tomcat (servidor contenidor d’aplicacions). Un cop acabat el procés s’ha integrat dins de MapFish canviant el codi JavaScript corresponent de la web original.

Millora i implementació de l’eina Open-Source AC2GeoNetwork per ArcCatalog

L’ETC-LUSI ha modificat l’aplicació de publicació de les metadades al portal de GeoNetwork amb l’objectiu de presentar i millorar la publicació de les mateixes, adaptant-se a la nova tipologia d’arxius d’emmagatzematge de les darreres versions del software de la casa ESRI, així com poder-les fer arribar al major nombre d’usuaris possible interessats en el intercanvi d’informació cartogràfica

Herramientas open source para la creación de portales

En aquest treball es proposa una aproximació al món del codi font obert des del punt de vista de la realització de portals col·laboratius i les seves eines involucrades. Per fer-ho, es passa revista als diferents tipus d'aplicacions, plataformes i utilitats que trobem disponibles, i s'agrupen en diferents categories: infraestructura i sistemes, serveis de comunicació, serveis de comunitat, serveis genèrics de portal, eines d'interacció amb sistemes mòbils, eines per al desenvolupament i prova i llibreries de suport.

Plataforma de correo y entorno colaborativo open source

Desplegar una solución fiable, potente y escalable de correo electrónico, en combinación de un entorno colaborativo de aplicaciones, bajo el apadrinamiento de software open source.

Plan de empresa para el desarrollo de nuevas líneas de negocio basadas en soluciones Open Source : Empresa: Most Servicios Informáticos S.L.

Elaboración de un plan de empresa para Most Servicios Informáticos S.L. para el desarrollo de nuevas líneas de negocio basadas en soluciones Open Source.

Estudio de la evolución de los sistemas Open Source de BI durante la última década.

El presente documento tiene por objetivo identificar la evolución que ha tenido la inteligencia de negocios en la ultima década, para determinar en que punto se encuentra y para donde va, además de identificar las alternativas de desarrollo que tiene, apalancándose con las Tecnologías de la Información, y más específicamente con las herramientas empaquetadas de BI de tipo Open Source.Así mismo, la presente investigación identifica las prácticas más convenientes, para sistematizar la elección y adaptación de la inteligencia de negocios en las organizaciones, analizando estas en uncaso exitoso real de implantación de la inteligencia de negocios sobre una herramienta BI tipo Open Source.

Open to the users' needs : combining user-centered design, standards and open source software

This case study introduces our continuous work to enhance the virtual classroom in order to provide faculty and students with an environment open to their needs, compliant with learning standards and, therefore compatible with other e-learning environments, and based on open source software. The result is a modulable, sustainable and interoperable learning environment that can be adapted to different teaching and learning situations by incorporating the LMS integrated tools as well as wikis, blogs, forums and Moodle activities among others.

Reuse of paths in light source animation

In this paper we extend the reuse of paths to the shot from a moving light source. In the classical algorithm new paths have to be cast from each new position of a light source. We show that we can reuse all paths for all positions, obtaining in this way a theoretical maximum speed-up equal to the average length of the shooting path

OpenNebula y Hadoop : Cloud Computing con herramientas Open Source

El presente proyecto consiste en una introducción al "cloud computing" y un estudio en profundidad de las herramientas OpenNebula, dentro del modelo IaaS (Infraestructure as a Service), y Hadoop, dentro del modelo PaaS (Platform as a Service). El trabajo también incluye la instalación, integración, configuración y puesta en marcha de una plataforma "cloud computing" utilizando OpenNebula y Hadoop con el objetivo de aplicar los conceptos teóricos en una solución real dentro de un entorno de laboratorio que puede ser extrapolable a una instalación real.

Open source software expectations in retail businesses of Igualada : an exploratory study

The emergence of open source software in the last years has become a common topic of study in different fields, from the most technical characteristics to the economical aspects. This paper examines the current status about the literature dealing with economics of open source and explores the uses, infrastructure and expectations of retail businesses and institutions of the town of Igualda about it. This qualitative case study finds out that the current equipment and level of uses of ICTs are low and that the current situation of the town stores is receptive to a potential introduction of open source software.