Location: Corn Insects and Crop Genetics ResearchTitle: Biomass production and composition of temperate and tropical maize in central Iowa
|Infante, Pedro - IOWA STATE UNIVERSITY|
|Moore, Ken - IOWA STATE UNIVERSITY|
|Hurburgh, Charlie - IOWA STATE UNIVERSITY|
|Archontoulis, Sotirios - IOWA STATE UNIVERSITY|
|Lenssen, Andrew - IOWA STATE UNIVERSITY|
|Fei, Shui-zhang - IOWA STATE UNIVERSITY|
Submitted to: Agronomy Journal
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 5/28/2018
Publication Date: 6/1/2018
Citation: Infante, P., Moore, K., Hurburgh, C., Scott, M.P., Archontoulis, S., Lenssen, A., Fei, S. 2018. Biomass production and composition of temperate and tropical maize in central Iowa. Agronomy Journal. 8(6):88. https://doi.org/10.3390/agronomy8060088.
Interpretive Summary: Corn management in the U.S. Corn Belt is optimized for production of grain. These management practices may not be optimal for production of corn for second generation biofuels, which would use non-grain parts of the plant as a feedstock as well as the grain. In this study, we examined the effects of alternative management practices on traits of interest to second generation biofuel feedstock production. Increased plant density was particularly effective at increasing above ground biomass, especially when combined with tropically adapted corn variates. In our best conditions, we were able to produce up to 25 Mg/ha of above-ground biomass, nearly twice the amount reported in previous studies. We also evaluated the impact of management practices on quality of the biomass produced. These results will be important for decision makers who are determining the economic feasibility of second generation biofuels. In addition, they will serve as management guidelines for producers of second generation biofuel feedstock.
Technical Abstract: Bioethanol production in the Midwestern U.S. has largely focused on corn (Zea mays L.) grain for starch-based ethanol production. There has been growing interest in lignocellulosic biomass as a feedstock for biofuels. Because corn adapted to the tropics does not initiate senescence as early as adapted corn, using tropical germplasm could improve biomass yield. This study compares the suitability of temperate and tropical corn with differing relative maturities as feedstocks for bioethanol production. Field trials were established in central Iowa during the 2014 and 2015 growing seasons. Six hybrids of different relative maturities were grown to evaluate total biomass production and feedstock quality under Midwestern U.S. conditions. Total biomass, height at the final leaf collar, stem diameter at one meter above ground, and lignocellulose concentration were measured at harvest. Tropical corn was taller and had greater non-grain and total biomass production (15% more than temperate corn), while temperate corn had greater grain yield and grain starch, as well as earlier maturation. Narrower row spacing had greater biomass and yield; nitrogen fertilization rate affected grain and feedstock composition. Tropical corn had lower cellulose, lignin, and ash concentrations and higher nitrogen at harvest than temperate corn. Conversely, temperate corn had greater ash, cellulose, and lignin concentrations. Tropical corn planted at high densities has high potential as a feedstock for bioethanol production in the U.S. Midwest.