Effects of elevated atmospheric carbon dioxide concentration and drought on soybean leaf photosynthesis

Soybean (Glycine max (L.) Merr. cv. Jack) was grown in the field in rain-protected plots to study effects of drought and atmospheric CO$\sb2$ enrichment on leaf gas exchange. Midday depressions in net leaf photosynthetic CO$\sb2$ exchange rates (Pn) were found in drought-stressed plants and the diurnal changes were mostly stomatal regulated, although accumulated drought stress eventually resulted in some non-stomatal limitations. However, seasonal changes in Pn were mostly limited by non-stomatal factors. Water use efficiency was always higher for drought stressed plants and depended on the severity of stress and associated stomatal or nonstomatal limitations. At enriched atmospheric CO$\sb2$ levels, stomatal limitations to Pn under drought stress were less important than at ambient atmospheric CO$\sb2$ levels. Morning and afternoon leaf starch levels were enhanced in both irrigated and nonirrigated plants in enriched CO$\sb2$. Afternoon starch levels were higher in stressed leaves than in non-stressed leaves at normal CO$\sb2$ levels.

Name thesis:degree_name

Ph.D.

Level thesis:degree_level

Dissertation

Discipline thesis:degree_discipline

Agronomy

Grantor

University of Illinois at Urbana-Champaign

Year dc:date

2011

Author dc:creator

• Chen, Xiaoming

Contributors dc:contributor

• Hesketh, John D.

• Agriculture, Agronomy
• Biology, Ecology
• Biology, Plant Physiology

Statement dc:rights

• Copyright 1994 Chen, Xiaoming

Language dc:language

eng

Identifier

AAI9503163
(UMI)AAI9503163

OAI identifier oai:identifier

oai:www.ideals.illinois.edu:2142/22610