EVALUATION OF NITROGEN FERTILIZATION AND GENOTYPE EFFECTS ON LODGING OF MISCANTHUS AND SWITCHGRASS

摘要

Energy grasses for use as solid fuels are harvested after winter, i.e. in early spring. But in regions withearly snow, lodging is a major risk leading to quality and yield losses. Visual lodging assessment was conducted toevaluate genotypic effects and effects of nitrogen fertilization on lodging susceptibility of miscanthus and switchgrassafter heavy snowfall. In a comparison of 15 miscanthus genotypes, strong differences in lodging behaviour wereobserved. All M. x sinensis genotypes and M. x sinensis hybrids showed high lodging damage. Greatest resistance tolodging was observed in the genotype M. x sacchariflorus (score of 5.33) and M. x giganteus (scores of 5.00 and3.33). The level of nitrogen fertilizer only had an effect on the lodging susceptibility of switchgrass, where lodgingincreased with each increment in nitrogen level. No influence of nitrogen fertilization was observed on the lodgingbehaviour of M. x giganteus. It was concluded that the selection of lodging resistant genotypes of miscanthus andadapted nitrogen fertilization regimes in switchgrass can become important factors for securing biomass supply fromenergy grasses in colder regions where early snow fall frequently occurs.