Development of Arbuscular Mycorrhizal Fungi-Organic Fertilizer Pellets Encapsulated with Alginate Film

A novel formulation consisting of arbuscular mycorrhizal fungi (AMF) spores mixed with sterilized organic fertilizer (AMF-F) encapsulated by an insoluble calcium alginate film was developed to enhance AMF efficacy and stability.The hardness of the pellets increased from 7-8 N to approximately 80 N by increasing the alginate concentration of the coating film from 1 to 3%.The AMF spore germination rate for the AMF and AMF-F pellets coated with calcium alginate films depended on the alginate concentration.A 2% sodium alginate formulation for the coating films resulted in optimal AMF spore germination rates and mechanical properties for handling, transport, and stability.The inclusion of a sterilized organic fertilizer in the encapsulated AMF-F pellets considerably induced AMF mycelial growth and helped prolong the shelf life of the pellets.In soil, the AMF-F pellets encapsulated with alginate (cAMF-F) initially degraded faster than the alginate-encapsulated AMF pellets (cAMF).However, both types of pellets were fully degraded within 30 days.It was demonstrated that cAMF and cAMF-F could promote colonization and provided resistance to drought stress in maize potted plants.