Enhancing Stability and Efficacy of Trichoderma Bio-Control Agents through Layer-by-Layer Encapsulation for Sustainable Plant Protection

Agricultural fungicide pollution poses a significant environmental challenge and carries adverse consequences for human health. Therefore, strategies to limit fungicide usage have gained paramount importance. Trichoderma fungi, owing to their antagonistic activity against various pathogenic fungi, have emerged as prospective candidates for enhancing both the effectiveness and sustainability of plant protection. Nevertheless, the utilization of bio-control agents like Trichoderma has unveiled new challenges, notably their vulnerability to physical stimuli and diminished efficacy during prolonged storage. To overcome these drawbacks, we present a mild and scalable encapsulation method for Trichoderma spores, employing a layer-by-layer (LbL) encapsulation approach using biobased lignin derivates. Our investigations demonstrate that the LbL-encapsulation technique imparts remarkable improvements in spore stability, even under adverse conditions such as variable temperature and prolonged exposure to UV irradiation compared to unencapsulated spores. Notably, encapsulated Trichoderma spores exhibit increased efficiency in the cultivation of tomato plants when compared to their unencapsulated counterparts. Additionally, our findings reveal that the in planta efficacy of encapsulated spores is contingent upon the specific Trichoderma strain employed. The results outlined herein suggest that Trichoderma spores, encapsulated within lignin through the LbL approach, exhibit potential as promising and sustainable alternative to chemical fungicides and potential commercialization.