Plants modify their metabolic processes in order to be capable to cope actively with unfavorable environmental conditions to ensure their survival in severe conditions. For this purpose, they form secondary plant metabolites, most of which have an anti-oxidative potential, providing 'sun protection', for example, when photosynthetic performance is restricted by limited water supply. Vice versa, it is possible to selectively accumulate target metabolites in plants through abiotic stress conditions. These can be seen as a natural resource and contained in the residual green biomass of plants at the end of the cultivation period in a circular bioeconomic approach.
In this context, the BioSC project InducTomE (www.biosc.de/inductome) and the BMBF project TaReCa (www.fz-juelich.de/ibg/ibg-2/EN/Research/Projects/TaReCa/TaReCa_node.html) focused on the stress-induced enrichment of target metabolites in tomato and bell pepper leaves, respectively, to use them in a cascade-designed sustainable biorefinery approach with further analysis in metabolic processes and bio-economic effects.Furthermore, in the ligth of climate change, crops or varieties that deliver stable performance and high quality under unfavorable or even extreme conditions are crucial. In view of finite phosphorus reserves and future water shortages in large areas, the EU project TOMRES (www.tomres.eu) focused on tomatoes that achieved a comparable yield with fewer resources.