Effect of saline stress on plasma membrane structure and function of barley roots

Abstract EN

Barley (Hordeum vulgare L.

cv.

Black Local) plants were grown hydroponically under different saline stresses (50, 100, 150 and 200 mM NaCl).

The adverse effect of each saline stress on the structure and functio of root cells palsma membrane was studied in terms of root surface ATPase activation by NaCl in the reaction mixture.

The concentration of NaCl in the reaction mixture was 0, 50, 100, 150 and 200mM.

ATPase activity was found to be increased gradually at certain concentrations of NaCl.

For control and 50mM stressed plants, the increase in root surfase ATPase activity was started at 150mM NaCl.

For lOOmM stressed plants it was started at lOOmM NaCl.

For 150 and 200mM stressed plants it was started at 50mM NaCl.

Results indicated that the adverse effect of the growth medium saline stresses on the integrity of the plasma membrane was started at lOOmM saline stress.

Accordingly the role of plasma membrane bound ATPase in active ion transport was disturbed at lOOmM saline stress and may be impaired at 150 and 200mM saline stresses.

It was suggested that the lipid environment of the plasma membrane surrounding ATPase was modified by the saline stresses 100-200mM.