ELEVATED CO2 EFFECTS ON SORGHUM GROWTH AND YIELD

Authors: OTTMAN, M - UNIVERSITY OF ARIZONA; Pinter Jr, Paul; Kimball, Bruce; VANDERLIP, R - KANSAS STATE UNIVERSITY; Wall, Gerard - Gary; LEAVITT, S - UNIVERSITY OF ARIZONA; La Morte, Robert; Waichulaitis, Stephen

Submitted to: Agronomy Abstracts
Publication Type: Abstract Only
Publication Acceptance Date: 10/31/1999
Publication Date: N/A
Citation: Ottman, M.J., Pinter Jr, P.J., Kimball, B.A., Vanderlip, R.L., Wall, G.W., Leavitt, S.W., La Morte, R.L., Waichulaitis, S.R. 1999. Elevated co2 effects on sorghum growth and yield. Agronomy Abstracts. pp 20.

Interpretive Summary:

Technical Abstract: The purpose of this work is to determine the effect of elevated CO2 on sorghum (Sorghum bicolor L. Moench) growth and yield under well-watered and water-stressed conditions. Sorghum was planted in late July at Maricopa, AZ, and flood irrigated frequently (well-watered) or only twice (water-stressed). A CO2 enrichment of 200 umol mol-1 was applied using free-air CO2 enrichment (FACE) in rings 21 m in diameter. Elevated CO2 did not significantly affect total yield or grain yield under well-watered conditions. Under water-stressed conditions, however, elevated CO2 increased grain yield from 472 to 553 g m-2 and total plant yield from 1176 to 1332 g m-2. The grain yield increase under water stressed conditions was due to increased kernels per head and not kernel weight or heads per unit area.