Lyophilized Biopolymeric Beads of Chitosan-Xanthan with Edible Fungus Laccaria Laccata (scop.) Cooke As Forest Ectomycorrhizal Biofertilizers

Objective: To evaluate whether or not the spores of the edible fungus Laccaria laccata (Scop.) Cooke encapsulated in a lyophilized biopolymeric matrix of chitosan-xanthan can cause ectomycorrhization in Pinus greggii Englem. trees under greenhouse conditions. Methodology: Spores of the edible ectomycorrhizal fungus L. laccata were encapsulated in beads made with the chitosan-xanthan biopolymer. The embedded spores were analyzed using scanning electron microscopy to evaluate possible structural damage. Next, these beads were used as biofertilizers in a greenhouse bioassay using Pinus greggii plants to evaluate their ability to be ectomycorrhized. The bioassay lasted 270 days. Subsequently, stereoscopic and bright field microscopy was used to determine if the roots of the pines had been subjected to an ectomycorrhizal colonization. Additionally, the growth of inoculated plants was evaluated compared to non-inoculated plants, 180 and 270 days after sowing. Results: The spores of L. laccata encapsulated in the biopolymeric matrix formed ectomycorrhizae in the roots of P. greggii. The percentages of ectomycorrhizal colonization in the plants ranged from 80 to 90%, demonstrating that the production of chitosan-xanthan biopolymeric beads can maintain the viability of the spores of the ectomycorrhizal fungus evaluated and extensively colonize the roots of Pinus greggii. Study Limitations/Implications: The biopolymeric matrix beads that contain spores of the fungus L. laccata can induce ectomycorrhization in trees of forest importance. Conclusions: The spores of an edible ectomycorrhizal fungus encapsulated in the chitosan-xanthan biopolymer have potential as a forest biofertilizer, which opens the opportunity to scale its use up to an industrial level.