Techniques to improve technological and sanitary quality

Agronomical ways for better quality and safety Choice of cultivar is an efficient way to obtain higher grain quality. Intercropping legumes (grain or forage) improves weed competition and N availability for wheat crop or succeeding crop. Green manure can be an effective alternative to farmyard manure. Fertilization with readily available nitrogen improves yield and quality when water is available. Reduced tillage affects soil fertility and wheat yield but has little effects on grain quality. Technological ways for better quality and safety Milling process strongly influences flour characteristics. Stone milling improves nutritive value; characteristics remain very stable independent of the milling yield. Flour characteristics from roller milling appear very susceptible to the milling yield. Increasing the milling yield in the aim of enriching nutritional quality has a detrimental effect either on safety (DON) or on bread-making quality (bread volume)

Technological quality of organic wheat in Europe

The demand for high quality organic bread wheat is increasing. The quality level of organic wheat harvested in EU is mainly dependant on variety, environmental conditions and agronomic practices. In some countries, protein content and composition, influencing technological value, are equivalent to those produced under conventional practices. Beside agronomical techniques, technological processes can help to maintain a good quality. Pre-treatments before milling such as debranning were found to be efficient in reducing DON contamination. The project highlighted the necessity to redefine the methods to assess the quality of organic wheat

Integrated physiological and agronomic modelling of N capture and use within the plant

Today farmers have several constraints to take into account in managing their crops: (i) competitiveness: productivity must be maintained or increased whereas inputs must be decreased, (ii) the environmental consequences of cultural practices: pesticide and fertilizer use must be decreased, and (iii) product quality must be improved and nitrogen nutrition is an important factor in harvest quality. These new constraints sometimes conflict: maximum yield is often obtained with large amounts of N, increasing the risks of N leaching. The determination of rates and dates for nitrogen application must become more precise in this context. Tools are required for the forecasting of crop requirements, the diagnosi

Varietal adaptation of a model simulating the grain protein content of winter wheat

National audienc

Symbiose fixatrice de l'azote des légumineuses : principes de fonctionnement, impacts agronomiques et environnementaux

National audienc

The Azodyn crop model as a decision support tool for choosing cultivars

International audienceWe evaluated the Azodyn wheat crop model as a cultivar decision support tool using a set of 14 genotypes, tested in 21 contrasting environments. The results showed that the Azodyn crop model satisfactorily simulated yield and grain protein content for a large range of genotypes and environments, as shown by a root mean square error of 1.4 Mg ha-1 and 1.7 g 100 g MS-1, respectively. The comparison between the observed and the simulated rankings of genotypes showed a ranking error of the model of one rank or less. The model was able to identify the best genotype to be used to obtain the highest yield in 20 cases out of 33 and the highest grain protein content in 48 cases out of 64. As a new way to evaluate crop models as a decision support tool for cultivar choice, we compared the Azodyn predictive accuracy against the cultivar yield and grain protein average generally used by cultivar growers as a predictive model. We showed that in the main production conditions, the Azodyn predictions fit the yield and grain protein content observed better than the average

Effects of soil structure on pea (Pisum sativum L.) root development according to sowing date and cultivar

International audienceSpring peas are known to be very sensitive to compaction, particularly when sowing takes place soon after winter. Winter peas, which are sown in autumn, should present an opportunity to sow the crop in better soil structural conditions than for spring peas, because of more favourable moisture conditions at that time. As environmental conditions have a big influence on root systems, it is important to determine the effects of soil structure on pea root systems for different cultivars and sowing dates. A spring pea cultivar and a winter pea cultivar were both sown at two dates (one in autumn and one in spring) on soils with different plough-layer structures (compacted and uncompacted) at two sites in 2002 and one site in 2003. Soil structure was characterised by bulk density and the percentage of highly compacted zones in the ploughed layer. Root distribution maps were produced every month, from February to maturity. Root development was described in terms of general root dynamics, root elongation rate (RER) in the subsoil, final maximum root depth (Dmax) and root distribution at maturity. Root depth dynamics depended on compaction and its interaction with climatic conditions. The effects of compaction on RER in the subsoil depended on the experimental conditions. Dmax was reduced by 0.10 m by compaction. Compaction also reduced root distribution between 10 and 40% in the ploughed layer only. Pea cultivars differed in sensitivity to soil compaction, with a direct effect on the final depth explored by roots. These results are discussed in terms of their relevance to water and nutrient uptake

Weed response and crop growth in winter wheat-lucerne intercropping: a comparison of conventional and reduced soil-tillage conditions in northern France

International audienceChanging agricultural practices from conventional to conservation tillage generally leads to increased weed populations and herbicide use. To gain information about the possible use of lucerne (Medicago sativa L.) cover crop as an alternative and sustainable weed-control strategy for winter wheat (Triticum aestivum L.), an experiment was performed at Thiverval-Grignon, France, from 2008 to 2010. We compared conventional and reduced tillage as well as the presence 5 and absence of living mulch (i.e. lucerne) on weeds and wheat production. Percentage soil coverage and aboveground biomass of wheat, lucerne and weeds were measured at the end of grain filling. Weed communities were analysed in terms of composition and diversity. During both seasons, wheat biomass did not significantly decrease in reduced-till trials compared with conventional ones (7.0 and 7.2 t ha –1 , respectively, in 2008–09; 6.9 and 7.1 t ha –1 in 2009–10). Regardless of soil management, the percentage soil coverage by wheat significantly decreased when it was intercropped, although 10 wheat biomass was not significantly reduced compared with the sole crop. To minimise cash-crop losses, we studied the competition between wheat, lucerne and weeds, testing various herbicide strategies. Early control of lucerne allowed better balance between weed control and wheat development. In addition, weed communities varied among treatments in terms of abundance and composition, being reduced but more varied in plots associated with lucerne. A functional group analysis showed that grasses benefited from reduced-till conditions, whereas problematic weeds such as annuals with 15 creeping and climbing morphologies were substantially reduced. In addition, annual and perennial broad-leaf species with rosette morphology were also significantly decreased when lucerne was used as living mulch. Wheat production in reduced-till conditions intercropped with lucerne living mulch may be useful for integrated weed management, reducing the need for herbicides. Additional keywords: cover crop, plant biomass, reduced inputs, weed biocontrol, weed diversity