Claim · model-written summary
Substomatal CO2 pressure stayed constant in most soybean leaves during the cycles and was above photosynthetic saturation
- Taxon
- soybean
Glycine maxe1 - Outcome
- substomatal carbon dioxide pressuree4
- Qualifier
- constant in the majority of leaves examinede4
Not reportedMaterialGeneCompoundOrgan / stageInteractorInteractor roleSecond interactorSecond interactor roleTreatmentComparatorSettingDirectionValue
Organisms pictured · Representative pictures of the matched species, not figures from the paper.

Verbatim
e1“for single leaves of soybean (Glycine max L. Merr.) plants held at 30 °C”
e4“During these cycles the substomatal carbon dioxide pressure was constant in the majority of leaves examined, and was always above saturation for photosynthesis”
Title
JAMES A. BUNCE Journal of Experimental Botany 1987. doi:10.1093/jxb/38.9.1413
Other claims from this paper (10)
- Intervention effect A sudden increase in leaf-to-air vapour deficit made soybean photosynthetic rate and stomatal conductance decrease after a lag of about 10 min
- Observation Soybean photosynthetic rate and stomatal conductance cycled in phase with each other
- Observation The soybean cycles had a period of about 20 min
- Observation Most soybean stomata changed in aperture during the cycles, and very few were fully closed
- Observation Water potential of soybean excised discs changed by at most 0.1 MPa between the minima and maxima of transpiration rate
- Intervention effect In sunflower leaves grown at low PPFD, the increase in VPD decreased photosynthesis
- Intervention effect In sunflower leaves grown at low PPFD, the increase in VPD caused leaf wilting
- Observation Sunflower turgor and photosynthesis recovered as stomatal conductance began to decrease
- Observation In sunflower, photosynthesis and conductance cycled approximately 180° out of phase
- Mechanism Decreased leaf conductance induced by high VPD is suggested to signal a decrease in soybean photosynthesis at CO2 saturation by a mechanism not related to mesophyll water deficit