Presentation: 2025 ND EPSCoR Annual conference 

October 21, 2025, NDSU Memorial Union, Fargo, North Dakota

Delivering Beneficial Mycorrhizal Fungi via Polymeric Seed Coating: Does Polymeric Seed Coating Promote Mycorrhizal Symbiosis?

Common agricultural practices, such as applying fertilizer and fungicide, often reduce or deplete microorganisms known to be beneficial for crop growth and soil sustainability. This experiment aimed to examine the efficacy of a method to incorporate arbuscular mycorrhizal fungi (AMF) into crop production using a biocompatible polymeric material as a seed coating, with the goal of supporting re-establishment of beneficial fungal relationships in agriculture and restoration settings. We investigated whether attaching AMF spores directly to seeds allowed germinating plants to establish a beneficial mycorrhizal relationship. Corn, flax, and soybean seeds were surface-sterilized and treated as follows: 1) seeds alone, 2) seeds planted into a spore inoculum with no coating (traditional approach), 3) seeds coated with polymer without AMF spores, and finally 4) seeds coated with AMF spores. Seeds were planted into cone-tainers with an autoclaved soil-sand mixture and placed in indirect light to germinate. Seedlings were transferred to a growth chamber at 23 ℃ with a 12 h light/dark cycle for early growth, then moved to the greenhouse. After about two months, plants were harvested, above and belowground biomass were measured and root samples taken for analysis of mycorrhizal colonization. Preliminary results of biomass data suggest there was no effect of AMF inoculation on growth of flax and soybean when seeds were treated with the AMF seed coating. However, corn treated with the AMF seed coating grew more poorly than corn grown with the seed coating without AMF. Future plans include confirming root colonization by AMF applied as seed coatings, DNA extraction and molecular identification of the AMF involved in root colonization, and conducting additional experimental trials.