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Achievements from conducted research as part of the team of the Laboratory of Traffic Engineering Transportation (LICIT) of IFSTTAR are integrated in platforms in order to develop and test new modules directly on real data. The ARCHIPEL platform focuses on data assimilation and fusion from multiple sources. The objective of ARCHIPEL is therefore to provide tools to process real-time data from different sources. This platform allows one to test and compare different approaches of assimilation and data fusion: loops, GPS, Bluetooth. Besides it offers to view details of traffic conditions in the form of space-time diagram on accurate and successive areas or larger areas by traficolor representation. In the context of ISpace&Time project, the city of Paris has been finely modelled in a traffic simulator developed by the LICIT, called SymuVia. This permits to have access to a case study in which we know all vehicle positions. In order to explore which fusion method is the most suitable depending on the context e.g. penetration rate and data noises, this realistic data has been put in the platform database and is utilized to give a complete overview of the more relevant methodology to apply. In this work, we propose some fusion scenarios and present the comparison results with respect to different conditions. The final aim is to give a roadmap of the more accurate solutions, since the ground truth is exactly known.

AbstractTo obtain a fast estimation of the total impurity density distribution in a poloidal cross section from soft X-ray (SXR) measurements during quasi-stationary phases, the possibility that ionization equilibrium may have little influence on the emissivity profile of Ni and Fe in the core region of tokamak plasmas is investigated. Preliminary and encouraging results that support this assumption under certain conditions are found. A simplified approach aimed at computing a satisfactory estimation of the total density of a unique and identified impurity directly from an absolutely calibrated SXR tomographic inversion is implemented. An example of application to a previously and independently performed transport simulation of a Ni injection in Tore Supra is then given.

To understand yield limitations imposed by the source–sink relationship and the effects that breeding had on it, the source–sink ratio was modified on 24 durum wheat cultivars released in different periods. Field experiments were conducted during 3 yr, with treatments consisting of removing the flag‐leaf blade, degraining half of the spike, and intact checks. Grains from near‐basal spikelets tended to be the most sensitive to source–sink modifications. Degraining increased grain weight up to 15% in modern cultivars, which were more source limited and more responsive to source–sink modifications than the old ones. Our results suggest a source–sink colimitation for grain filling in Mediterranean environments. Translocation of preanthesis assimilates was responsible for 25, 27, and 33% of grain weight in old, intermediate, and modern cultivars, respectively. Defoliation did not alter dry matter translocation (DMT) from the main stem, as the reduction in translocation of leaf blades was compensated with translocation increases from the chaff. Sink demand determined DMT that was mostly regulated by the stem. Our results indicate that future yield improvements may be achieved by strengthening the source capacity.

This study evaluates the breeding of durum wheat (Triticum turgidumL. var. durum) during the 20th century with respect to yield and grain carbon isotope discrimination (Δ), and their relationship with plant height, harvest index (HI), days from sowing to anthesis, and days from anthesis to maturity. Twenty‐four cultivars released before 1945 (old), between 1950 and 1985 (intermediate), and between 1988 and 2000 (modern), and previously characterized by whether dwarfing genes were present (semidwarf) or absent (tall), were selected from germplasm obtained in Italy and Spain. Experiments were conducted in six environments with average yields ranging from to 2113 to 4827 kg ha−1. The total absolute genetic gain in yield across countries from before 1945 to 2000 was 20 kg ha−1yr−1(51% of increase), which represents a relative genetic gain of 0.61% yr−1. Yield gains led to a loss of stability. The mean increase in Δ13C was 6% (0.014‰ yr−1or 0.09% yr−1). Early heading and a long grain‐filling period were correlated with high yields in the tall cultivars. Increased plant height and low Δ13C values were associated with high yields for the semidwarf cultivars, while a long grain‐filling period was not advantageous for semidwarf cultivars.

A set of ten durum wheat genotypes was grown in experiments conducted under four contrasting Mediterranean conditions during three years to assess the effect of latitude and water regime on grain growth and grain yield formation. The relationship between grain weight and accumulated growing degree-days (GDD) from anthesis was described by a logistic equation and final grain weight (W) and maximum rate (R) and duration (D) of grain filling were calculated from the fitted curves. Thousand kernel weight (TKW) was positively related to grain yield at both latitudes and water regimes, although the contribution of the number of grains per m 2to final yield was only significant in the south, where environmental constraints likely limited the achievement of a large grain set. Differences in final grain weight between latitudes could be mostly explained by differences in the grain filling rate, while changes on Wbetween water regimes were due to altered grain filling durations. Under northern conditions grain yield was positively associated to grain filling duration but negatively related to the maximum rate of grain filling, while in the south the coefficients of the grain filling curves had little or no effect on final yield. Reductions in grain yield under rainfed conditions were due to the fall in the number of grains per m 2since TKW was not significantly affected by drought.

Grain yield of durum wheat (Triticum turgidumL. var. durum) under Mediterranean conditions is frequently limited by both high temperature and drought during grain growth. Path coefficient analyses, based on an ontogenetic diagram, were conducted to study grain yield formation under different temperature and moisture regimes across Spain. Six ICARDA–CIMMYT inbred lines and four Spanish commercial cultivars were grown during 1998 and 1999 at two temperature regimes (cool and warm) and under both rainfed and irrigated conditions. Path coefficient analysis revealed that grain yield under cooler conditions was mostly determined by kernel weight, whereas the number of spikes per square meter predominantly influenced grain production in the warmer environments. The number of kernels per spike had a significant contribution to grain yield, especially under drought stress conditions. These associations do not clearly appear in the simple correlation analysis. Compensatory effects among yield components were almost absent in the cooler environments, probably due to the relative availability of water and N during the critical phases of plant development. Contrarily, under warmer conditions, negative effects of the number of spikes per square meter were registered on both the number of kernels per spike and kernel weight. Path analysis appears to be a useful tool for understanding grain yield formation and provides valuable additional information for improving grain yield via selection for its yield components.

The effect of environment on the relationship between grain carbon isotope discrimination (Δ) and yield was studied for durum wheat (Triticum turgidumL. var. durum) under Mediterranean conditions. A group of 25 genotypes was grown under contrasting water regimes in two regions of Spain during three years. The first objective was to determine the environmental factors responsible for the strong positive relationship previously observed between Δ and yield across trials. Environmental factors tested were total water input (Wi), mean temperature, accumulated reference evapotranspiration (ET0), and the ratio Wi/ET0during different periods of the crop cycle. Water input during grain filling was the variable most strongly correlated with grain Δ and yield across all the trials, as well as across the subset of trials in northeastern Spain. In southeastern Spain, the most drought prone of the two regions, Wifrom sowing to heading explained the most variation in grain Δ and yield. The second objective was to study the effect of environment on the relationship between Δ and yield across genotypes. No significant correlation was found for trials with a mean yield up to about 2000 kg ha−1, but the strength of the relationship increased sharply and attained significance in trials yielding 2500 kg ha−1When yield above 2500 kg ha−1the correlation between Δ and yield remained relatively steady and positive, with an rvalue around 0.5. It is concluded that breeding to raise durum wheat yield in Mediterranean conditions could take advantage of selecting for higher Δ only in relatively wet years or under supplementary irrigation.

Future wheat yield improvements may be gained by increasing total dry matter (TDM) production. Vegetation indices (VI) based on spectral reflectance ratios have been proposed as an appropriate method to assess TDM and leaf area index (LAI) in wheat. This study was undertaken to determine whether VI could accurately identify TDM and LAI in durum wheat {Triticum turgidumvar. durum(Desf.) Bowden [= Tturgidumsubsp. durum(Desf.) Husn.]} and serve as indirect selection criteria in breeding programs. Total dry matter and LAI were determined from destructive sampling from booting to milk‐grain in seven field experiments conducted under Mediterranean conditions. Each experiment included one of two sets of 20 or 25 genotypes. Field reflectance values were collected using a portable field spectroradiometer. Two VI, the normalized difference vegetation index (NDVI) and the simple ratio (SR), were derived from spectral measurements and their predictive value for TDM and LAI was evaluated. The best stages for growth trait appraisal were Stages 65 and 75 of the Zadoks scale. The power of VI for assessing TDM was lower than their predictive value for LAI. The suitability of VI for the assessment of growth traits depended on the range of variability existing within the experimental data. Vegetation indices accurately tracked changes in LAI when data were analyzed across a broad range of different growth stages, environments, and genotypes. However, their value as indirect genotypic selection criteria for TDM or LAI was limited, since they lacked predictive ability for specific environment/growth stage combinations.

The relationships between carbon isotope discrimination (Δ) in mature kernels, canopy temperature depression (CTD) during anthesis and grain filling, 1000-kernel weight (TKW), total carbon content of mature kernels, and yield were studied in durum wheat (Triticum turgidum L. var. durum) grown in Spain (western Mediterranean basin). Twenty-five durum wheat genotypes were grown in 2 regions (NE and SE Spain) and under 2 water regimes (rainfed v. support irrigation) from 1997 to 1999 (i.e. a total of 12 trials). Principal component analysis placed yield and Δ on the same axis. Pearson’s correlation and stepwise analysis confirmed that Δ was the trait that best assessed genotype differences in yield within trials, and was followed, at a considerable distance, by TKW. Our results also demonstrated the extremely poor performance of CTD throughout the wide range of growing conditions in this study. drought, kernel weight, kernel carbon content.

The relationships between various morphophysiological traits and yield were studied in durum wheat (Triticum durum Desf.) grown in Mediterranean conditions. Two sets of 22 genotypes were used. One was developed for semi-humid environments (TA-genotypes) and was cultivated in 22 trials around the Mediterranean basin with a mean yield across genotypes and environments of 4925 kg/ha. The other set was developed for drier conditions (CA-genotypes) and was cultivated in 15 trials, with a mean yield of 3501 kg/ha. Morphophysiological traits for each set were evaluated in 2 trials with contrasting water regimes conducted in north-eastern Spain: Lleida-rainfed (LR) and Lleida-irrigation (LI). Two kinds of traits were evaluated: developmental traits, including early vigour, plant height, and phenology (days from planting to heading and to maturity); and traits related to photosynthetic performance such as canopy temperature and chlorophyll content of the flag leaf, both measured during grain filling, and carbon isotope discrimination of mature grains. All the traits, measured in both Lleida trials, were related to the mean yield of the same genotypes across all the sites where they were cultivated. Yield measured at either of the 2 environments at Lleida was a much poorer predictor of genotype differences in mean yield than most of the traits. Nevertheless, the kind of environment where the morphophysiological traits were evaluated affected the performance of these traits as yield predictors. The combination of significant traits measured in the better environment (LI) explained 71% and 55% of genotype variability in yield within TA- and CA-genotypes, respectively, but only 56% and 27% when they were evaluated at LR. On the other hand, growing conditions of the yield trials was the main factor determining the best combination of traits. For TA-genotypes, larger yields were associated with shorter plants and higher carbon isotope discrimination (Δ) of grains, and to a lesser extent with higher early vigour and lower canopy temperature, whereas phenological traits made no contribution to explaining genotype differences in yield. For the CA-genotypes, higher yields were related to an earlier heading date or alternatively to a higher chlorophyll content during grain filling. A higher Δ in mature kernels also seems to be a positive trait. canopy temperature, carbon isotope discrimination, chlorophyll content, drought, early vigour, phenology, plant height.