Ion movements during stomatal opening in darkness after illumination under nitrogen

In Zea mays L., Bryophylum laxiflorum Bak., Gossypium hirsutum L., Helianthus annuus L., Oryza sativa L. and Vigna radiata L., a pre-illumination in nitrogen causes transient stomatal opening upon returning the plant to darkness and normal air. In Zea mays L. hybrid INRA 508, K⁺ and Cl⁻ fluctuations in the stomatal complex during this stomatal opening in darkness were similar to those observed during a light-induced opening in normal air. These results are consistent with a two-phase mechanism for stomatal opening: a light phase that may occur in the absence of oxygen and carbon dioxide, and a dark phase during which oxygen is necessary for ion accumulation and other mechanisms of osmotic adjustment.