title: Solute Accumulation in Tobacco Cells Adapted to NaCl.
abstract: Cells of Nicotiana tabacum L. var Wisconsin 38 adapted to NaCl (up to 428 millimolar) which have undergone extensive osmotic adjustment accumulated Na(+) and Cl(-) as principal solutes for this adjustment. Although the intracellular concentrations of Na(+) and Cl(-) correlated well with the level of adaptation, these ions apparently did not contribute to the osmotic adjustment which occurred during a culture growth cycle, because the concentrations of Na(+) and Cl(-) did not increase during the period of most active osmotic adjustment. The average intracellular concentrations of soluble sugars and total free amino acids increased as a function of the level of adaptation; however, the levels of these solutes did not approach those observed for Na(+) and Cl(-). The concentration of proline was positively correlated with cell osmotic potential, accumulating to an average concentration of 129 millimolar in cells adapted to 428 millimolar NaCl and representing about 80% of the total free amino acid pool as compared to an average of 0.29 millimolar and about 4% of the pool in unadapted cells. These results indicate that although Na(+) and Cl(-) are principal components of osmotic adjustment, organic solutes also may make significant contributions.
authors: Department of Horticulture, Purdue University, West Lafayette, Indiana 47907.
authors: M L
authors: ML
authors: Binzel
authors: P M
authors: PM
authors: Hasegawa
authors: D
authors: D
authors: Rhodes
authors: S
authors: S
authors: Handa
authors: A K
authors: AK
authors: Handa
authors: R A
authors: RA
authors: Bressan