EN
We analysed changes in the activity of phosphofructokinase (PFK) and phosphoenolopyruvate carboxylase (PEPC), and in the glucose and sucrose contents of Norway maple seeds stratified at 3°C (dormancy broken) or treated at temperature 15°C (dormancy not broken). We found that changes in the activity of enzymes are not linear, and 2-3 stages may be distinguished. Dormancy breaking and seed germination is associated with a high activity of PFK and PEPC, and a high glucose level in embryo axes.