The Mycorrhizal Fungus, Sebacina vermifera, Enhances Seed Germination and Biomass Production in Switchgrass (Panicum virgatum L)

Seed dormancy and slow seedling establishment are two major concerns in switchgrass (Panicum virgatum L.) production, often resulting in a poor stand with reduced productivity. Studies were conducted to investigate the stability of artificial associations between switchgrass and the ectomycorrhizal fungus, Sebacina vermifera, and to evaluate the potential benefits of this novel association in seed germination and biomass production. All six strains of S. vermifera tested had a high frequency of colonization on switchgrass roots of a synthetic cultivar NF/GA-993. The positive effects of the associations were reflected in plant height, root length, and biomass production. Inoculated plants produced as much as 75%, 113%, and 18% more shoot biomass than un-inoculated control plants in the first, second, and third harvest, respectively, with no consequent reduction in root biomass. Further, culture filtrates from some strains of S. vermifera increased seed germination in the switchgrass cultivar Kanlow by 52% over the control (p<0.05). This study illustrates the great potential of microbial associations to increase biomass production and productivity of switchgrass.