Miscanthus x Giganteus Propagated From Plugs and Rhizomes Exhibits Similar Yields with Different Morphology.

Propagation and establishment of the biomass crop Miscanthus x giganteus is largely accomplished using rhizomes.  However, live plants (plugs) generated in greenhouses can also be used for establishment, and may present economic and logistical advantages over rhizomes.  A field experiment was conducted at 3 sites in Iowa to determine the relative performance of the different planting stock in Midwest plantations.  Second year yields were not significantly affected by planting stock within a location or between locations, and ranged from 20.4 – 27.8 Mg ha^-1 (P > 0.05).  However, significant morphological differences were observed between plants established from rhizomes or plugs.  Averaged over sites, the height of plants grown from rhizomes was 193.7 ± 5.5 cm whereas plug generated plants were 176.0 ± 5.5 cm (P < 0.05).  Plants grown from rhizomes also had fewer tillers, (P < 0.01) with an average of 31.8 ± 0.6 tillers compared to plug generated plants which had 38.9 ± 0.6 tillers.  Tillers from rhizome plants were thicker than tillers from plants grown from plugs (P < 0.01).  Rhizome plants exhibited 8.5 ± 0.09 mm stem diameters on average, while plug plants had an average stem diameter of 7.8 ± 0.09 mm.  Results indicate establishment of Miscanthus x giganteus from plugs can provide the same biomass as achieved from rhizomes, but differential morphology exists between the two propagation methods.