Stomatal aperture size

Range onset of experiment 06:00 2.0±1.6 µm: at 11:00 7.4±2.3µm: at 13:00 6.2±2.1μm µm
Organism Broadbean Vicia faba
Reference Outlaw WH Jr, De Vlieghere-He X. Transpiration rate. An important factor controlling the sucrose content of the guard cell apoplast of broad bean. Plant Physiol. 2001 Aug126(4):1716-24 p.1717 right column 2nd paragraphPubMed ID11500569
Method P.1722 left column bottom paragraph: "Finally, (d) another peel, from the opposite side of this leaflet, was stained with 0.03% (w/v) aqueous neutral red and stomatal aperture sizes were determined microscopically."
Comments P.1717 right column 2nd paragraph: "Control experiments (upper, Fig. 1) were conducted on plants that were maintained at 60% RH. The guard cell apoplast Suc content was low at the onset of the photoperiod (0600 h, 97 ± 81 femtomol [fmol]/guard cell pair) and was correlated with a small stomatal aperture size (2.0 ± 1.6 μm). No significant changes took place in this Suc pool (P> 0.11, compared with 0600 h) or in stomatal aperture size over the next 3 h. By 1100 h, however, the guard cell apoplast Suc content had increased (P < 0.02 for all earlier values) by 7-fold to 701 ± 142 fmol/guard cell pair (upper, Fig. 1). This highest value in guard cell apoplast Suc content during the photoperiod was correlated with the largest stomatal aperture size (7.4 ± 2.3 μm, P < 0.01). The increase in guard cell apoplast Suc content during the photoperiod was approximately 145 mM (for conversion factors, see Ewert et al., 2000). In these experiments, the apparent decreases between 1100 h and 1300 h in guard cell apoplast Suc content (to 504 ± 77 fmol/guard cell pair, P > 0.11) and in stomatal aperture size (to 6.2 ± 2.1 μm) were not significant."
Entered by Uri M
ID 115009