Monoiodoacetic Acid and Stomatal Movement

Fig’ I ‘ Effect of monoiOdoacetic acid on ATPase activity in guard cells of Commelina communis L’ With closed Stomata in the dark : Ieft, in control medium ; middle’ in medium containing 10-4M monoiodoacetic acid ; and right, in medlum contalnlng 10 M mono iodoacetic acid’ x 100

Effect of Monoiodoacetic Acid on Stomatal Movement

Fujino M. (1969)

Masayoshi Fujino – Biological Institute, Faculty of Education, Nagasaki University, Nagasaki, Japan

Sci. Bull. Fac. Educ., Nagasaki Univ. 20: 57-66 –

https://core.ac.uk/download/pdf/58761342.pdf

Effect of monoiodoacetic acid on stomatal movement was studied using
lower epidermis of Commelina communis L.. In the medium containing 10-4
M monoiodoacetic acid stomatal opening and potassium absorption into guard
cells were remarkably accelerated both in the light and in the dark.
On the other hand, in the medium containing 10″4 M monoiodoacetic acid
stomatal closing and excretion of potassium from guard cells were remarkably
inhibited both in the light and in the dark.

These results support following hypothesis presented by present. authors
(Fujino 1967) : Stomatal movement is caused by active transport of potassium
between guard cells and mesophyll. ATP in guard cells is involved in absorption
of potassium, while ATPase is responsible in excretion of potassium from
guard cells. Most of ATP which is necessary for the stomatal movement
is produced by respiration. Light is probably involved in ATPase in-activation.