Photosynthetic and hydraulic changes caused by water deficit and flooding stress increase rice’s intrinsic water-use efficiency

Rui Zhu, Tiesong Hu, Fengyan Wu, Yong Liu, Shan Zhou and Yanxuan Wang

Agricultural Water Management, 2023, vol. 289, issue C

Abstract: Effects of water deficit and flooding stress on rice’s intrinsic water-use efficiency (iWUE) and how iWUE variations are linked to stress-induced physiological changes are poorly understood. Here, we proposed a model-based approach to analyze iWUE across datasets and its relationship with physiological changes, using only leaf gas exchange data and plant hydraulic vulnerability parameters. We applied this approach to a leaf gas exchange dataset of rice, measured during the post-stress period of water deficit and flooding experiments. Results show that water deficit and flooding stress decreased rice’s photosynthetic capacity (Vcmax25) and water transport capacity (Kmax) during the post-stress period, and that these physiological changes altered the relationship between photosynthetic rate and stomatal conductance, leading to an increase in iWUE. Nevertheless, improved iWUE cannot avoid the yield reduction. Interestingly, the stress-induced decrease in Vcmax25 was significantly correlated with the decline in Kmax. The Vcmax25-Kmax relationship was significantly different between the water deficit and flooding treatments, with the slope of the latter being closer to 1:1. Model predicts that stress-induced disproportionate Vcmax25-Kmax co-reduction improved iWUE while maintaining a relatively high intercellular to atmosphere CO2 concentration ratio; this may represent optimal coordination between photosynthetic and hydraulic traits in response to stress. Our work has important implications for using leaf gas exchange data to diagnose variations in iWUE, and for improving our understanding of crop physiological responses to environmental stresses.

Keywords: Stomatal optimization model; Stomatal conductance; Photosynthesis; Water stress; Maximum hydraulic conductance (search for similar items in EconPapers)
Date: 2023
References: View references in EconPapers View complete reference list from CitEc
Citations: View citations in EconPapers (1)

Downloads: (external link)
http://www.sciencedirect.com/science/article/pii/S037837742300392X
Full text for ScienceDirect subscribers only

Related works:
This item may be available elsewhere in EconPapers: Search for items with the same title.

Export reference: BibTeX RIS (EndNote, ProCite, RefMan) HTML/Text

Persistent link: https://EconPapers.repec.org/RePEc:eee:agiwat:v:289:y:2023:i:c:s037837742300392x

DOI: 10.1016/j.agwat.2023.108527

Access Statistics for this article

Agricultural Water Management is currently edited by B.E. Clothier, W. Dierickx, J. Oster and D. Wichelns

More articles in Agricultural Water Management from Elsevier
Bibliographic data for series maintained by Catherine Liu ().