Viajar a través del Cosmos: la medida de la creación de riqueza y la serie histórica del producto interior bruto en España (1850-2008)

Este trabajo responde a la réplica de Leandro Prados de la Escosura acerca de mi estimación de la serie histórica del Producto Interior Bruto de España (R.E.A., 49 (XVII), 2009, págs. 5 a 45). Demuestra que el IPC es el mejor deflactor disponible para reconstruir el PIB antes de la CNE porque mide correctamente las variaciones interanuales del nivel general de precios. Emplea un procedimiento de enlace de la serie histórica de la contabilidad nacional que es consistente con los nuevos sistemas de cuentas nacionales SCN-93 y SEC-95 y coincide con los empleados por todos los organismos económicos internacionales. La actualización del sistema contable, con la inclusión de la economía sumergida y de la producción para uso final propio, ha dejado obsoletas las estimaciones anteriores y exige estimaciones de segunda generación, con la inevitable readaptación de los niveles relativos de las distintas economías.

Series enlazadas de empleo y VAB para España, 1955-2010 (RegDat_Nac versión 3.0)

En este trabajo se elaboran series de distintos agregados de empleo y de VAB a precios corrientes y constantes para el conjunto de España durante el período 1955-2010. Las series se construyen mediante el enlace de diversas bases de la CNE y de la Contabilidad Trimestral, introduciéndose también una corrección tentativa para reconciliar las series de empleo de la CNE con las de la EPA.

Series enlazadas de empleo y VAB para España, 1955-2010 (RegDat_Nac versión 3.1)

En este trabajo se elaboran series homogéneas de distintos agregados de empleo y de VAB a precios corrientes y constantes para el conjunto de España durante el período 1955-2010. Las series se construyen mediante el enlace de diversas bases de la CNE y de la Contabilidad Trimestral, introduciéndose también una corrección tentativa para reconciliar las series de empleo de la CNE con las de la EPA.

Effects of crop and weed densities on the interactions between barley and Lolium rigidum in several Mediterranean locations

The effects of both barley and Lolium rigidum densities on weed growth and spike production and on crop yield were examined in five field experiments carried out in the Mediterranean drylands of Spain and Western Australia. The aim was to check the consistency of the competitiveness of the crop in different environmental and management conditions. L. rigidum reduced barley yields in most of the experiments (between 0 and 85%), the number of ears per m2 being the most affected. It was found that increasing the barley seeding rate did not reduce the crop losses but did limit weed biomass (between 5 and 61%) and spike production (between 24 and 85%). The variability observed in crop yield losses between sites and seasons was related to rainfall at the beginning of the season. The most sensitive component of yield to weed competition was the number of ears per plant.

Selection response of growth rate in rabbits for meat production

Genetic and environmental trends in 2 lines of rabbit (B and R) selected on individual weight gain (WG) from weaning (4 wk) to slaughter (11 wk) were estimated using mixed model methodology. Line B was derived from the California breed and line R was a synthetic of stock of different origin. The data were collected from a single herd and comprised 7 718 individuals in line B and 9 391 in line R, the lines having 12 and 9 generations of selection respectively. Realized responses in the 2 lines were 2.7% and 2.2% of the initial mean per year respectively and showed that selection on WG was effective but was less than expected. Selection on slaughter weight (SW) and effects of selection on other economic traits are discussed. It is concluded that selection on either WG or SW is a simple method for improving growth rate in rabbit sire line stocks.

Genetic variation for carbon isotope composition in Juglans regia L.: relationships with growth, phenology and climate of origin

Among the traits of breeding interest for the common walnut tree Juglans regia L., characteristics such as timing of budbreak and leaf fall, water-use efficiency and growth performance are regarded as being of utmost relevance in Mediterranean conditions. The authors evaluated intraspecific variation in $\delta$13C (carbon isotope composition, surrogate of intrinsic water-use efficiency, WUE$_{\rm i}$) for 22 J. regia families grown in a progeny test under supplementary irrigation, and investigated whether such variation correlated with climatic indicators of native habitats. The genetic relationships between $\delta$13C, growth and phenology were also assessed during two consecutive years. Overall, the most water-use-efficient families (i.e. with higher $\delta$13C), which originated mainly from drought-prone provenance regions which have a high vapour pressure deficit and low rainfall, exhibited less height growth and smaller DBH. Using a stepwise regression procedure, $\delta$13C was included as the main explanatory variable of genotypic variation in growth traits, together with growing season duration (for DBH in both years) and flushing (for height in 2007). It was concluded that WUE$_{\rm i}$ is largely unconnected to phenology effects in the explanation of growth performance for J. regia, therefore suggesting the opportunity of simultaneously selecting for low WUE$_{\rm i}$ and extended growing period to maximise productivity in non-water-limited environments.