Direct Measurements of Turgor Pressure Potentials: III. (A) INJECTIONS OF SOLUTIONS INTO STOMATAL CELLS, AND (B) COMPARISONS OF PRESSURE POTENTIALS IN STOMATAL CELLS OF DIFFERENT SPECIES

Attempts were made to inject different substances into epidermaland stomatal cells in order to observe their movement from cellto cell and their effects on guard cell metabolism. Althoughinjections of neutral red were successful and provided usefulinformation, injections of ABA and KCl did not yield any worthwhileresults. Measurements of pressure potentials in stomatal cells of fourspecies were carried out. These throw light on the role of epidermalturgor in influencing stomatal movements and thus on hypothesesof a mechanical advantage of subsidiary cells.