THE HIGH REDUCING SUGAR CONTENT DURING GERMINATION CONTRIBUTES TO DESICCATION DAMAGE IN LETTUCE (LACTUCA-SATIVA L) RADICLES

At the time of protrusion, radicles of lettuce seeds became susceptibl e to desiccation damage. Concomitant with radicle elongation, both the reducing sugar content and the amount of lipid-aldehydes increased. T he role of the hydroxy- and lipid-aldehydes in browning reactions that occurred during desiccation and re-imbibition was analysed. It was co ncluded that both types of aldehydes reacted with amino-groups during desiccation and that the increase in lipid-aldehydes during germinatio n could be due to the augmented reducing sugar content. Therefore, the high reducing sugar content in radicles of germinated lettuce seeds m ay be the primary source of hydroxyl radicals, and thereby, a principa l cause of desiccation damage.