Further Evidence in Support of an Interactive Model in Stomatal Control

The interaction between CO₂ IAA, ABA, and temperature in thecontrol of stomatal behaviour, was investigated in the chill-resistantPisum sativum and chill-hardened Phaseolus vulgaris. It wasfound that the ability of kBA to induce stomatai closure wasdependent upon the presence of CO₂ in both species, at bothtemperatures (22 ?C, 5?C) Similarly, the ability of IAA to decreasestomatal resistance, was dependent upon the presence of CO₂in both species, at both temperatures. Chilling at 5?C in thelight did not influence the response characteristics of stomatato CO₂ ABA or IAA, in either species. These results are discussedin relation to a model of the interactions of these regulatorsof stomatal aperture. Key words: Stomata, modelling, chilling