title: Characteristics of cultured tomato cells after prolonged exposure to medium containing polyethylene glycol.
abstract: Cell lines of tomato (Lycopersicon esculentum Mill., cv. VFNT-Cherry) have been isolated, which are capable of growing in media containing polyethylene glycol (PEG) 6000 with water potentials as low as -15 or -22 bar. After prolonged exposure to media containing PEG, these cell populations have reduced abilities to grow in the absence of PEG. Upon resuspension in PEG-free medium, the cells swell and begin to release metabolites, including protein. Measurement by plasmometry of the osmotic potential of cells selected in medium with -22 bar water potential indicates that they maintain, at the end of the growth cycle, an osmotic potential of approximately -26 bar. This is compared to an osmotic potential of -9 bar for nonselected cells in medium without PEG, having an initial water potential of -4 bar. Thus, considerable osmotic adjustment occurs as a result of exposure to external low water potential. The results also indicate that PEG does not contribute significantly to osmotic adjustment of the cells.
authors: Department of Horticulture, Purdue University, West Lafayette, Indiana 47907.
authors: A K
authors: AK
authors: Handa
authors: R A
authors: RA
authors: Bressan
authors: S
authors: S
authors: Handa
authors: P M
authors: PM
authors: Hasegawa