Evaluate the effect of sowing date and maturity class on grain yield and WUE and NUE of barley and soft wheat managed under no-till conditions.

 In western Mediterranean areas, sowing delay under no-till can increase grain yield, WUE and NUE of winter barley, and also of wheat but only during wet years.

 Elucidate the impact of tillage and different sources and rates of nitrogen fertilization on cereal production and water and nitrogen use efficiencies under Mediterranean conditions.

 The use of no-till and the application of agronomic rates of N as pig slurry leads to greater barley yield and water-and nitrogen-use efficiencies than the traditional management based on conventional tillage and mineral N fertilization.

 Evaluate the impacts of introducing grain legumes and cover crops in completely redesigned cropping systems (i.e. adapting all management practices) on wheat yield and grain quality to reduce N fertilizer and irrigation dependence.

 Under temperate sub-mediterranean conditions, properly designed cropping systems that simultaneously insert grain legumes and cover crops reduce N requirements and show similar wheat yield and grain quality attributes as those that are cereal-based.

 Quantify the impact of the incorporation of grain legumes and cover crops on soil organic carbon (SOC) and soil organic nitrogen (SON) in rotations with an increasing number of grain legumes managed under conventional tillage

 In conventionally-tilled grain legume-based rotations, the use of cover crops is efficient to mitigate SOC and SON losses and then increase N use efficiency at the cropping system level without reducing productivity.