Abstract: | The kinetics of sugar efflux from slices of sugar beet rootswas investigated using washing solutions of different osmoticpressure and calcium concentration. The leakage of sucrose isstrongly reduced in solutions of high osmotic pressure (>0·8MPa) or high calcium concentration (10 mM). Turgor-dependentnecrosis of parenchyma cells (plasmoptysis) is the main causeof sucrose efflux from the tissue in hypotonic media with lowcalcium activity. This was shown by good correlation betweenthe percentage of leaked sucrose and the percentage of tissuewater, which was in the free space after the washing procedure.The kinetics of sugar leakage from beet root parenchyma is nobasis for the estimation of the sugar contents of the free spaceor the cytoplasm in situ. |