Submitted to: American Society of Agronomy Branch Meeting
Publication Type: Abstract Only
Publication Acceptance Date: 1/15/2010
Publication Date: 2/8/2010
Citation: Rocateli, A.C., Raper, R.L., Arriaga, F.J., Balkcom, K.S., Bransby, D. 2010. A New Spin On An Old Crop for Bioenergy: Sorghum. American Society of Agronomy Branch Meeting. CDROM. Interpretive Summary:
Technical Abstract: Seeking alternative and renewable sources of energy is necessary due to oil price fluctuations, environmental and national security concerns. Additionally, Southeastern U.S. has been affected by drought conditions over several years. For these reasons, sorghum may be a reasonable alternative as an energy crop, since it is drought and nematode resistant. Sorghum could be integrated into a conservation system as part of a crop rotation with typical cash crops of the region. While much emphasis has been placed on perennials, annual crops could provide a major source of biomass for cellulosic bioenergy production. New varieties of sorghum which are capable of producing extremely high amounts of biomass have not been fully investigated as part of Southeastern U.S. conservation systems. The types of sorghum evaluated were: grain sorghum (GS), high biomass forage sorghum (FS), and photoperiod-sensitive sorghum (PS). These sorghum types, and a typical corn (Pioneer 31G65) were grown under two different tillage systems (conventional and conservation tillage) and with and without irrigation in 2008 and 2009. Additionally, a rye cover crop was integrated to maximize biomass produced and to provide ground cover during the winter. Biomass production was higher in 2008 (18.43 Mg/ha) than in 2009 (11.64 Mg/ha) due to higher natural precipitation in 2009 which affected crop development. In 2008, PS (26.04 Mg/ha) had the highest biomass production followed by FS (22.83 Mg/ha), GS (13.41 Mg/ha) and corn (8.92 Mg/ha) after 18 weeks of planting. But, in 2009, GS (11.51 Mg/ha) had higher production than FS (9.62 Mg/ha). Additionally, different applied tillage systems did not affect biomass production in 2008, but conservation system showed higher biomass production in 2009. These findings suggest that conservation tillage has an advantage for sorghum production in these conditions, including other benefits such as reduction in fuel use, compaction and erosion.