Details

Autor(en) / Beteiligte

• Wall, G W
• Brooks, T J
• Adam, N R
• Cousins, AB
• Kimball, BA
• Pinter, PJ Jr
• LaMorte, R L
• Triggs, J
• Ottman, MJ
• Leavitt, S W
• Matthias, AD
• Williams, D G
• Webber, AN

Titel

Elevated atmospheric CO sub(2) improved Sorghum plant water status by ameliorating the adverse effects of drought

Ist Teil von

• The New phytologist, 2001-11, Vol.152 (2), p.231-248

Erscheinungsjahr

2001

Quelle

Wiley Online Library Journals Frontfile Complete

Beschreibungen/Notizen

• The interactive effects of atmospheric CO sub(2) concentration and soil-water content on grain sorghum (Sorghum bicolor) are reported here. Sorghum plants were exposed to ambient (control) and free-air CO sub(2) enrichment (FACE; ambient + 200 mu mol mol super(-1)), under ample (wet, 100% replacement of evapotranspiration) and reduced (dry, postplanting and mid-season irrigations) water supply over two growing seasons. FACE reduced seasonal average stomatal conductance (g sub(s)) by 0.17 mol (H sub(2)O) m super(-2) s super(-1) (32% and 37% for dry and wet, respectively) compared with control; this was similar to the difference between dry and wet treatments. FACE increased net assimilation rate (A) by 4.77 mu mol (CO sub(2)) m super(-2) s super(-1) (23% and 9% for dry and wet, respectively), whereas dry decreased A by 10.50 mu mol (CO sub(2)) m super(-2) s super(-1) (26%) compared with wet. Total plant water potential ( psi sub(w)) was 0.16 MPa (9%) and 0.04 MPa (3%) less negative in FACE than in the control treatment for dry and wet, respectively. Under dry, FACE stimulated final shoot biomass by 15%. By ameliorating the adverse effects of drought, elevated atmospheric CO sub(2) improved plant water status, which indirectly caused an increase in carbon gain.