|ACHARYA, MOHAN - University Of Arkansas|
|BURNER, DAVID - Retired ARS Employee|
|FELIX, FRITSCHI - University Of Missouri|
|ADAMS, TAYLOR - University Of Arkansas|
Submitted to: American Journal of Plant Sciences
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 11/6/2018
Publication Date: 11/9/2018
Citation: Acharya, M., Burner, D.M., Ashworth, A.J., Felix, F., Adams, T. 2018. Growth rate of Giant Miscanthus (Miscanthus x giganteus) and Giant Reed (Arundo donax) in a low-input system in Arkansas, USA. American Journal of Plant Sciences. 9:2371-2384. https://doi.org/10.4236/ajps.2018.912172.
Interpretive Summary: Carbon dioxide released from the combustion of fossil fuels increases atmospheric CO2, however, replacement of fossil fuels with biofuels could decrease atmospheric CO2 levels. Miscanthus and giant reed are two perennial grasses that are capable of producing biofuels by direct combustion, anaerobic digestion, or alcoholic fermentation. Growth rate of miscanthus and giant reed varies depending on water table, temperature, photoperiod, and soil nutrient status. The aim of this study is to compare growth rate and dry weight per stalk of miscanthus and giant reed under a low-input system in Arkansas, USA. Giant reed had a greater growth rate and dry weight per stalk and plants were taller compared to miscanthus. These results show that giant reed under current climatic conditions and no additional input of fertilizers and herbicide, can grow to 358 cm producing stalk dry weight of 192 g per stalk with a production cycle of more than 7 years. For sustainable bioenergy production from giant reed in Arkansas, further studies should be performed to determine a sustainable number of harvests per year and associated production costs.
Technical Abstract: The US Department of Energy is currently building strategies for the expansion of clean and renewable energy sources, and tall, rapidly-growing grasses such as giant miscanthus (Miscanthus × giganteus) and giant reed (Arundo donax) are two of the many of species that could fill this renewable energy niche. Our objective was to compare stalk growth components of giant miscanthus and giant reed, in a low-input system in Arkansas, USA. Due to the potential invasiveness of giant reed, our study was conducted on an upland site to minimize escape. Plant height and dry weight per stalk were measured every week for two consecutive growing seasons in 2012 and 2013. Leaf area index (LAI) was measured every two weeks from May to September in 2012. A significant species × day interaction occurred for plant height and dry weight per stalk, due to the relatively greater height and weight of giant reed compared to giant miscanthus after May. Stalk elongation rate was greater for giant reed than giant miscanthus (1.85 and 1.11 cm day-1, respectively). Leaf area index differed between species, giant reed (10.4 m2 m-2) > giant miscanthus (4.4 m2 m-2). We showed that giant reed produced taller, heavier stalks, and had a greater stalk elongation rate, compared to giant miscanthus. Growth and yield of both species need to be studied across a range of sites and management inputs before either is recommended for on-farm production.