Abscisic acid affects on stomatal development in Arabidopsis thaliana

Abstract

Plant regulates its transpiration by controlling the size of the stomatal pore. In addition to such rapid responses, the number of stomata is also regulated by environmental factors. The phytohormone abscisic acid (ABA) is known to regulate stomatal closure in response to the changing water status. It is reported that ABA-induced stomatal closure is impaired in Arabidopsis ABA-insensitive mutants, abi1-1 and abi2-1. In this study, we found that the density and size of stomata were increased in the abi1-1 and abi2-1 mutants. We also found that ABA-deficient aba2-2 mutant also showed the similar phenotypes. These data indicate that ABA regulates stomatal differentiation.