Nano/microencapsulation of plant biocontrol agents by chitosan, alginate, and other important biopolymers as a novel strategy for alleviating plant biotic stresses

Biological biocides have the potential to reduce plant biotic stresses and boost development, but they tend to be unstable and degrade quickly. BCAs inhibit plant diseases and enhance crop productivity while being eco-friendly. Encapsulation research has increased in recent decades in response to the growing need for BCAs. These formulations can address the difficulties of free-form formulations. They can improve the efficacy of BCAs by prolonging their shelf life and offering the controlled release of biological components. Using a novel approach, they can be a potential platform for controlling biotic stressors, especially plant pathogens. Chitosan and alginate are two important biopolymers with great potential in enclosing BCAs. These can also be used alone for encapsulation, but their application in composite form eliminates the disadvantages of using them alone. However, several other biopolymers have significant roles in formulating BCAs, such as gums, gelatin, starch, and pectin. Given the amazing potential of these new formulations, this comprehensive review highlights more recent developments about encapsulating BCAs based on nano and micro-materials and their appliances in reducing plant biotic stressors. These prospects might provide the foundation for future opportunities to expand the efficacy and application BCAs by formulation technologies to combat plant pathogens.