Interaction between physiological age and cold treatment on the composition and concentration of carbohydrates in chicory roots (Cichorium intybus L.)

The concentration of free sugars (glucose, fructose and sucrose) and inulin was measured in chicory roots (Cichorium intybus L. var, foliosum cv. Flash) during two growing seasons. Roots were harvested approximately every 2 weeks between June and October. They were either used immediately for sugar analysis or after a cold treatment. After the final harvest, samples were taken during the whole storage period of several months. The evolution pattern of free sugars and inulin during the growing season was very similar to previously reported data. When the long storage period after the vegetative growing year was considered, the changes in free sucrose (increase), and inulin bound glucose and fructose (decrease) mainly occurred at the first 60 days of storage. The apex was not necessary for perception of the cold signal. From the start of the growing season, cold treatment caused a strong decrease in free glucose and increases in free fructose and sucrose. Thus, still very young roots reacted to cold treatment by hydrolysis of inulin. Even at this young stage, the apex was not necessary for perception of the cold signal.