Freeze-Thaw Injury to Isolated Spinach Protoplasts and Its Simulation at Above Freezing Temperatures

Freeze-thaw injury to isolated spinach protoplasts and its simulation at above freezing temperatures.

Possibilities to account for the mechanism of freeze-thaw injury to isolated protoplasts of Spinacia oleracea L. cv. Winter Bloomsdale were investigated. A freeze-thaw cycle to -3.9 C resulted in 80% lysis of the protoplasts. At -3.9 C, protoplasts are exposed to the equivalent of a 2.1 osmolal solution. Isolated protoplasts behave as ideal osmometers in the range of concentrations tested (0.35...

Behavior of the Plasma Membrane of Isolated Protoplasts during a Freeze-Thaw Cycle.

Cryomicroscopy of protoplasts isolated from nonacclimated (NA) rye leaves (Secale cereale L. cv Puma) revealed that the predominant form of injury following cooling to the minimum temperature for 50% survival (LT(50)) (-5 degrees C) was expansion-induced lysis of the plasma membrane during warming and thawing of the suspending medium when the decreasing osmolality resulted in osmotic expansion ...

Freeze - Thaw Injury in Wood Frog Erythrocytes

In vivo detection of membrane injury at freezing temperatures.

The release of hydrogen cyanide from Amelanchier alnifolia was monitored at 30 C and -10 C following lethal freezing at both slow and fast rates. Assuming that hydrogen cyanide release indicates membrane damage, it was concluded that during a fatal freeze-thaw cycle membrane damage occurred during cell contraction and, therefore, was not dependent upon membrane area expansion during thawing.

Freezing injury and resistance in spinach chloroplast grana.

Spinach grana appear to be injured by the same mechanism and by the same degree of dehydration and volume reduction that injures animal cells. Winter-hardened or artificially protected grana avoid injury by permitting a reversible influx of solute which forestalls excessive dehydration and shrinkage.