A surrogate measure of stomatal aperture

It is proposed that a measurement of the peristomatal criterion for choosing a technique is scale of measurement: groove distance (PGD) of guard cells on surface depending on the purpose of the study, researchers may impressions of leaf epidermis can act as a surrogate wish to investigate the conductances of canopies, plants, measure of stomatal aperture. To test this idea, leaves, and sub-leaf areas, or the widths of individual investigations were carried out on two species, one in pores (van Gardingen et al., 1997). The characterization which it is possible to make direct measurements of of patches and trends in stomatal aperture over leaf pore width with relative ease (Commelina communis surfaces (Terashima et al., 1988; Downton et al., 1988; L.) and one whose stomata are so small that this is Smith et al., 1989) has renewed interest in methods difficult (Phaseolus vulgaris L.). Leaf water vapour appropriate for the whole leaf scale and below. Despite conductance measurements were first taken with a the fact that advances in IRGA-based porometry and porometer, then, without delay, a silicone rubber measurement of chlorophyll fluorescence allow direct and impression of the leaf was made of the area directly indirect measurement of stomatal activity in small areas under the porometer cup. From a positive replica of of leaves (Daley et al., 1989; Parkinson et al., 1990), this impression, stomatal aperture, PGD and pore there is still a need for accurate measurements of indi