As the EU is confronted with profound agriculture and environmental challenges, the development and adoption of more effective, safer and greener alternatives for crop protection is becoming increasingly critical, thus reducing the impact of current pesticides on human, animals and the environment as well as fighting pesticide resistance, a phenomenon that has been exacerbated by the extensive and non-targeted use of these products and climate change. Answering current challenges for the development of new sustainable bio-based alternatives for crop protection, ZELDA aims to validate a zero-waste biorefinery approach at TRL5 for developing a portfolio of broad-spectrum immune elicitors derived from lignocellulosic biomasses. Such products combining for the first time cello-oligos, hemi-oligos and lignin-based products will reverse the pesticide paradigm, supporting plants in raising their own defences against a wide range of pathogens while supporting plant growth and flowering. Lignin nanoparticles will also bring a microbicides effect for curative use, further enhancing product efficacy. By combining principles of Safe and Sustainable by Design that will establish a feedback loop for product implementation, the project will ensure that products are not only more effective, but also safer and more sustainable. Economic viability will be ensured by minimising the amount of product to be used: ZELDA’ success will rely on the use of AI-based smart delivery systems targeting specific areas of the crop that require to be treated. The products developed will be tested on key crops central to the EU diet (cereals, tomatoes and grapes) in different EU geographical and pedo- climatic areas, developing tailored crop protection strategies for improving food security and contributing to preserving biodiversity and the ecosystem.