Agronomic factors in the establishment of tetraploid seeded Miscanthus x giganteus

作者：Anderson Eric K; Lee DoKyoung; Allen Damian J; Voigt Thomas B^*

来源：Global Change Biology Bioenergy, 2015, 7(5): 1075-1083.

DOI：10.1111/gcbb.12192

• biomass
• cellulosic feedstock
• hydroseeding
• irrigation
• Miscanthusxgiganteus
• perennial grass
• planting method
• seeding rate

To meet US renewable fuel mandates, perennial grasses have been identified as important potential feedstocks for processing into biofuels. Triploid Miscanthusxgiganteus, a sterile, rhizomatous grass, has proven to be a high-yielding biomass crop over the past few decades in the European Union and, more recently, in the United States. However, high establishment costs from rhizomes are a limitation to more widespread plantings without government subsidies. A recently developed tetraploid cultivar of M.xgiganteus producing viable seeds (seeded miscanthus) shows promise in producing high yields with reduced establishment costs. Field experiments were conducted in Urbana, Illinois from 2011 to 2013 to optimize seeded miscanthus establishment by comparing seeding rates (10, 20, and 40seedsm(-2)) and planting methods (drilling seeds at 38 and 76cm row spacing vs. hydroseeding with and without premoistened seeds) under irrigated and rainfed conditions. Drought conditions in 2011 and 2012 coincided with stand establishment failure under rainfed conditions, suggesting that seeded miscanthus may not establish well in water-stressed environments. In irrigated plots, hydroseeding without premoistening was significantly better than hydroseeding with premoistening, drilling at 38cm and drilling at 76cm with respect to plant number (18%, 54%, and 59% higher, respectively), plant frequency (13%, 30%, and 40% better, respectively), and the rate of canopy closure (18%, 33%, and 43% faster, respectively) when averaged across seeding rates. However, differences in second-year biomass yields among treatments were less pronounced, as plant size partially compensated for plant density. Both hydroseeding and drilling at rates of 20 or 40seedsm(-2) appear to be viable planting options for establishing seeded miscanthus provided sufficient soil moisture, but additional strategies are required for this new biomass production system under rainfed conditions.

• 出版日期2015-9