In future, agricultural crop production will have to manage with less and less nitrogen fertilization. The goal must therefore be to increase nitrogen use efficiency so that yield levels can be kept stable. Plants respond to mild nitrogen deficiency by elongating their lateral roots. In this way, more nitrogen can be absorbed than before. Researchers at the IPK Leibniz Institute have now discovered a hormonal regulatory module that mediates the molecular processes of this adaptation. Brassinosteroids and auxins play a central role in this. The results were published in the journal Nature Communications.