Get 20M+ Full-Text Papers For Less Than $1.50/day. Start a 7-Day Trial for You or Your Team.

Learn More →

Effects of water deficit on photosynthetic capacity

Effects of water deficit on photosynthetic capacity Under drought, CO2 assimilation rates decrease already at small leaf water deficits. At least part of the inhibition is attributed to non‐stomata1 effects at the chloroplast level, with electron transport and phosphorylation being main targets of inhibition. These findings are questioned by direct measurements of photosynthetic capacity with systems that are not Limited by stomata, e.g. leaf slices in solution or leaves at ex‐ternal CO2 concentrations exceeding 5%. Here, photosynthesis was rather insensitive to dehydration down to 50–70% relative water content, and different plant species re‐sponded in a very similar way. More severe dehydration affected not only pboto‐synthesis, but also dark CO2 fixation and presumably also photorespiration. Rever‐sible and unspecific inhibition is thought to be mediated mainly by increased concen‐trations of solutes in dehydrated cells. Inhibition of photorespiration might favour photoinhibition when long‐term water stress is coupled with full sunlight. Photo‐inhibition, together with general senescence phenomena might be involved in long‐term effects of water stress under natural drought conditions. This offers an explanation for the conflicting results of short‐term water stress experiments and studies carried out under field conditions. http://www.deepdyve.com/assets/images/DeepDyve-Logo-lg.png Physiologia Plantarum Wiley

Effects of water deficit on photosynthetic capacity

Kaiser, Werner M.
Physiologia Plantarum , Volume 71 (1) – Jan 1, 1987
Download PDF
9 pages

Loading next page...
 
/lp/wiley/effects-of-water-deficit-on-photosynthetic-capacity-vE00t06TMU

References (39)

Publisher
Wiley
Copyright
Copyright © 1987 Wiley Subscription Services
ISSN
0031-9317
eISSN
1399-3054
DOI
10.1111/j.1399-3054.1987.tb04631.x
Publisher site
See Article on Publisher Site

Abstract

Under drought, CO2 assimilation rates decrease already at small leaf water deficits. At least part of the inhibition is attributed to non‐stomata1 effects at the chloroplast level, with electron transport and phosphorylation being main targets of inhibition. These findings are questioned by direct measurements of photosynthetic capacity with systems that are not Limited by stomata, e.g. leaf slices in solution or leaves at ex‐ternal CO2 concentrations exceeding 5%. Here, photosynthesis was rather insensitive to dehydration down to 50–70% relative water content, and different plant species re‐sponded in a very similar way. More severe dehydration affected not only pboto‐synthesis, but also dark CO2 fixation and presumably also photorespiration. Rever‐sible and unspecific inhibition is thought to be mediated mainly by increased concen‐trations of solutes in dehydrated cells. Inhibition of photorespiration might favour photoinhibition when long‐term water stress is coupled with full sunlight. Photo‐inhibition, together with general senescence phenomena might be involved in long‐term effects of water stress under natural drought conditions. This offers an explanation for the conflicting results of short‐term water stress experiments and studies carried out under field conditions.

Journal

Physiologia Plantarum – Wiley

Published: Jan 1, 1987

Keywords: ; ; ; ; ; ; ;

There are no references for this article.