Ultrastructural changes in gametophytes of Acrostichum aureum L. cultured in different sodium chloride concentrations

Abstract

Gametophytes cultured in solutions containing 0.0 to 0.7 % NaCl exhibited no change in ultrastructural organization of chloroplasts. In 1.0 % NaCl-grown gametophytes, there were thinner granal stacks, relatively larger spaces between granal thylakoidal membranes and larger plastoglobuli in the chloroplasts. These changes were accompanied by a decrease in photosynthesis. Cup shape, horseshoe shape, ring shape, and amoeboid mitochondria were observed in gametophytes grown in 0.0 to 0.7 % NaCl. Only round mitochondria were observed in the gametophytes grown in 1.0 % NaCl. Mitochondria seemed to be more resistant to salt stress compared to chloroplasts. There was no direct relationship between changes in respiration rate and changes in mitochondrial shape among gametophytes grown in different NaCl concentrations.