Current agricultural pest control is highly dependent on synthetic pesticides. These pose significant risks to the environment and human health. Microbial pesticides offer promising alternatives with greater specificity and reduced risk. However, their use is often hampered by ineffective formulations containing synthetic additives which pose an environment risk themselves. We propose to solve both problems by developing formulations that use only bio-sourced materials to stabilize the interface between two fluid media. The 2-Phase High Interface Materials (BIO2PHIMs) that form in this manner are ideal carries for a bacterial cargo, and have superior stability and application features as formulations. The projects main objectives are fourfold: (i) Improve bacterial fitness in biopesticide formulations using BIO2PHIMs as carriers. These materials not only resist destabilization, but also allow for the inclusion of nutrient-supplying mediums. (ii) Enable rational formulation design by developing models with predictive capabilities for the correlations between the physicochemical properties of BIO2PHIM, the viability of enclosed bacteria, and their post-deposition performance. (iii) enhancing the benefits of BIO2PHIM by identifying bacteria with high pesticide potential, improving application methods and monitoring the environmental impact of the formulations. (iv) Training a cohort of young scientist equipped with the necessary interdisciplinary knowledge to tackle the synthetic pesticide emission problem, and implement solutions. To achieve these goals, we will implement a truly multidisciplinary approach, bringing together expertise from microbiology, soft matter physics, physical chemistry, chemical and materials engineering and agricultural science. Realizing BIO2PHIM pesticides is at the heart of the MSCA work programme, as it will contribute to the EUs target of reducing the use of synthetic pesticides by 50% by 2030, as part of the European Green Deal.