A sufficient supply of nitrogen is one of the most essential factors in order to achieve high grain yields and quality of wheat, hence meeting the increasing food requirements of a growing world population. However, significant amounts of nitrogen can escape from the cropping system by leaching into groundwater or transformation into volatile atmospheric emissions. Therefore, although nitrogen fertilisation will continue to play a major role in the production of high crop yields in the future, the negative effects of nitrogen fertilisation on ecosystems must be reduced. At the same time, water and nutrient uptake is strongly impacted by drought events, which are increasing in degree and frequency in almost all relevant wheat cropping regions. Hence, there is a great need for a strategic development of varieties that achieve higher yields under reduced fertilisation and erratically occurring drought phenomena. Recently, this has led to a growing interest into the understanding of the root system, as the organ for water and nutrient uptake. However, knowledge about the development of wheat roots and their genetic control is still rather basic, primarily due to difficulties in measuring of root functions. Reliable molecular markers for relevant root traits can enable breeders to overcome difficulties with underground phenotypic selection. In this study we are creating near-isogenic lines of European elite winter varieties that carry introgressions of a major QTL which confers a larger root system. Backcross progenies are being subjected to foreground selection, using flanking KASP markers for the desired QTL alleles conferring the larger root system, while the genetic background of the elite varieties is being evaluated after each backcrossing step by background selection using genomewide markers. Furthermore, we are investigating the relevance of an increased root growth for enhanced water and Nuptake. This question will be clarified through (i) analysis of N-transfer with 15N labelled fertilisers in container experiments, and(ii) field trials conducted at three locations, in order to investigate nitrogen use efficiency and yield performance in different fertiliser levels and crop rotation scenarios.