Changes in Whole-Plant Metabolism during the Grain-Filling Stage in Sorghum Grown under Elevated CO2 and Drought

Author(s)

De Souza, Amanda P. ^[1] ; Cocuron, Jean-Christophe ^{[2, 3]} ; Garcia, Ana Carolina ^[1] ; Alonso, Ana Paula ^[2] ; Buckeridge, Marcos S. ^[1]

Affiliation

^[1] Univ Sao Paulo, Inst Biosci, Dept Bot, Lab Plant Physiol Ecol, BR-05508090 Sao Paulo - Brazil

^[2] Ohio State Univ, Dept Mol Genet, Columbus, OH 43210 - USA

^[3] Ohio State Univ, Ctr Appl Plant Sci, Columbus, OH 43210 - USA

• Document type: Journal article
• Source: Plant Physiology; v. 169, n. 3, p. 1755-1765, NOV 2015.
• Web of Science Citations: 10

Abstract

Projections indicate an elevation of the atmospheric CO2 concentration ({[}CO2]) concomitant with an intensification of drought for this century, increasing the challenges to food security. On the one hand, drought is a main environmental factor responsible for decreasing crop productivity and grain quality, especially when occurring during the grain-filling stage. On the other hand, elevated {[}CO2] is predicted to mitigate some of the negative effects of drought. Sorghum (Sorghum bicolor) is a C-4 grass that has important economical and nutritional values in many parts of the world. Although the impact of elevated {[}CO2] and drought in photosynthesis and growth has been well documented for sorghum, the effects of the combination of these two environmental factors on plant metabolism have yet to be determined. To address this question, sorghum plants (cv BRS 330) were grown and monitored at ambient (400 mu mol mol(-1)) or elevated (800 mu mol mol(-1)) {[}CO2] for 120 d and subjected to drought during the grain-filling stage. Leaf photosynthesis, respiration, and stomatal conductance were measured at 90 and 120 d after planting, and plant organs (leaves, culm, roots, prop roots, and grains) were harvested. Finally, biochemical composition and intracellular metabolites were assessed for each organ. As expected, elevated {[}CO2] reduced the stomatal conductance, which preserved soil moisture and plant fitness under drought. Interestingly, the whole-plant metabolism was adjusted and protein content in grains was improved by 60% in sorghum grown under elevated {[}CO2]. (AU)

• FAPESP's process: 13/50316-4 - Impact of elevated CO2 and drought on metabolism of Sorghum
• Grantee: Marcos Silveira Buckeridge
• Support Opportunities: Regular Research Grants
• FAPESP's process: 11/52065-3 - Using systems biology approach to develop a model for whole plant functioning
• Grantee: Marcos Silveira Buckeridge
• Support Opportunities: Research Grants - Research Partnership for Technological Innovation - PITE