The Effects of Temperature and ABA on Stomata ofZea maysL.

Abstract

Epidermal fragments were removed from maize leaves by tearing parallel to the veins. These were incubated at a number of different temperatures in several concentrations of ABA. The sensitivity of stomata to temperature was dependent upon the technique used to incubate epidermis. Generally, the widest apertures were recorded at around 25°C. In all experiments, stomata incubated at low (10°C) temperatures on 5.6 × 10⁻⁴ M ABA showed wider apertures than those incubated on distilled water. This ABA-stimulated stomatal opening was accompanied by an increase in the intensity of potassium staining in the guard cells. At 25 °C, epidermis incubated on several concentrations of ABA showed some stomatal closure, decreased potassium staining in the guard cells and increased potassium staining in the subsidiary cells.