The aim of this scientific activity is to select the most common alfalfa varieties in a 2-year cultivation trial (first year of cultivation in 2005), primarily with regard to their water consumption (water use efficiency), but also with regard to biomass yield (above and below ground) and N2 To test fixation performance in dry areas under organic farming conditions. The results are used to select suitable alfalfa varieties for the dry area in eastern Austria, the Marchfeld, and should be made immediately available to practice. By choosing suitable varieties, it is expected that the water consumption of alfalfa stands can be limited without major losses in dry matter.