Biomass Yield Response to Temperature for Three Tropical Grass Species.

Many crops produce biofuel feedstock such as lignocellulose. Matching the crop biophysical requirements to land characteristics is a strategy to help lower input cost and/or increase yield. Temperature is a land characteristic that can have a significant impact on yield. Field trials were conducted to quantify the effect of air temperature on the biomass yield of sugarcane (Saccharum officinarum), energycane (Saccharum officinarum x Saccharum robustum), and napier/napier hybrid (Pennisetum purpureum, Pennisetum purpureum x Pennisetum glaucum) on the island of Maui, Hawaii. Treatments were sites (30, 305, and 915 m above sea level) and species (three species and three cultivars of each species). Biomass yield was collected from 2011 to 2013. Sugarcane was harvested once. Energycane was harvested once a year and included one ratoon. Napier and napier hybrids were harvested every six months and included three ratoons. At elevations 90 and 305 m, sugarcane and energycane biomass yield were similar ranging from 72.8 to 82.0 Mg ha^-1, but significantly greater than napier/napier hybrids at 49.1 to 53.8 Mg ha^-1. At 915 m elevation, napier/napier hybrid yield was 52.4 Mg ha^-1 and significantly greater than sugarcane and energycane yield at 24.9 and 28.9 Mg ha^-1. The data indicate that sugarcane and energycane yield well in the lower elevation and napier/napier hybrids have the yield advantage at higher elevations. Fiber and sucrose data are also to be presented.