Extreme undersaturation in the intercellular airspace of leaves: a failure of Gaastra or Ohm?
Abstract
Recent reports of extreme levels of undersaturation in internal leaf air spaces have called into question one of the foundational assumptions of leaf gas exchange analysis, that leaf air spaces are effectively saturated with water vapour at leaf surface temperature. Historically, inferring the biophysical states controlling assimilation and transpiration from the fluxes directly measured by gas exchange systems has presented a number of challenges, including: (1) a mismatch in scales between the area of flux measurement, the biochemical cellular scale and the meso-scale introduced by the localization of the fluxes to stomatal pores; (2) the inaccessibility of the internal states of CO2 and water vapour required to define conductances; and (3) uncertainties about the pathways these internal fluxes travel. In response, plant physiologists have adopted a set of simplifying assumptions that define phenomenological concepts such as stomatal and mesophyll conductances.
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- Jul 27, 2022
- Source ID
- 10.1093/aob/mcac094
Entities
People
- Abraham D Stroock
- Annika E Huber
- Fulton E Rockwell
- N Michele Holbrook
- Piyush Jain
- Sabyasachi Sen
Organizations
- Air Force Office of Scientific Research
- Cornell University
- Harvard University