SENSITIVITY TO ABSCISIC ACID REGULATES STOMATAL OSCILLATION AND CLOSURE IN ARABIDOPSIS THALIANA

Stomatal oscillation has been described as an efficient mechanism to prevent water from loss, decrease the transpiration rate and to improve water use efficiency under severe drought conditions. Former researches demonstrated that ABA-induced H2O2 production and H2O2-activated Ca2+ channels were important mechanism for ABA-induced stomatal oscillation. In this study, the sensitivity to abscisic acid (ABA) for regulation of stomatal oscillation was investigated in Arabidopsis thaliana mutants (abi1-1, insensitive to ABA and era1-2, hypersensitive to ABA) and wild type. The results showed that (1) hypersensitive to ABA strengthen stomatal oscillation and closure induced by ABA; (2) insensitive to ABA abolish stomatal oscillation and closure induced by ABA; and (3) there is positive relationship between stomatal oscillation, closure and sensitivity to abscisic acid. These data indicate that sensitivity to ABA may regulate stomatal oscillation and closure in Arabidopsis thaliana.