THE INFLUENCE OF HEAT SHOCK AND DESSICATION ON BOXWOOD (BUXUS SEMPERVIRENS L.) LEAVES' PHOTOSYSTEM II AND ANTIOXIDANT SYSTEMS ACTIVITY

This research aimed to investigate the response of one- and two-year-old Box (Buxus sempervirens L.) leaves to the action of heat shock (HS) and desiccation. These factors influenced the photosystem II activity of the leaves and the degradation of hydrogen peroxide by leaf extracts. The development of these processes was specific depending on the age of the leaves and season of their collection for analysis. Thus, the studied characteristics could assure the elaboration of new, rapid methods of assessing the resistance of leaves to high temperatures, depending on the period (season) of vegetation and their age. At different seasons of the year, the resistance of box leaves to HS tends to correspond to seasonal temperatures, reaching the highest level in summer, intermediate level in spring and autumn, and the lowest in winter. Regardless of the season, the one-year-old leaves are more resistant and have a higher capacity to recover from HS damage than the two-year-old leaves.