Crop yield not only depends on mature plant performance (such as photosynthesis, nitrogen assimilation, resistance against pathogens…) but also on seed quality, from development to germination and seedling establishment. In fact, it is believed that poor seed quality causes a yield loss of up to 20% in many crops. This risk is likely to grow up with the necessary reduction of chemical inputs in farming. Therefore, having quality biomarkers to allow seed engineering is a crucial topic. In this project, called Isoseed, we intend to investigate, identify and validate seed quality biomarkers based on metabolism including natural isotope abundance. Metabolism is at the heart of key processes from emergence to germination and development (cellular energy production, reserve remobilization, protein synthesis, etc.) but quite critically, metabolic properties of seeds have never been extensively implemented to assess seed quality. The objective is to use wide spectrum metabolic analyses (metabolomics) and isotopes to select cultivars of crop plants that have been ranked for quality. The potential of the use of stable isotopes at natural abundance will be particularly examined. In effect, metabolic reactions select for isotopic forms (13C, 15N, 34S, 18O, 2H) so that changes in metabolic fluxes can be easily detected using natural isotope abundances. In addition, potential implementation of metabolic and isotopic markers is facilitated by the low cost and relatively high throughput of analyses.