PHYSIOLOGICAL RESPONSE OF LOCAL POPULATIONS OF SPECIES CYCLAMEN PURPURASCENS MILL. TO FOREST GAPS.

Aspect of forest dynamics is also the formation of forest gaps. Certain plant species typical for understory, still persists in newly formed forest gaps. For such species, environmental conditions change significantly. In research the physiological response of local populations of Cyclamen purpurascens Mill. in forest gaps, depending on time of their formation was examined. The physiological response was measured as anthocyanin and quercetin content in cyclamen leaves, depending on forest gap and season. It was found that anthocyanin content in leaves from all gaps was statistically higher in autumn than in spring. A comparison of anthocyanin content between leaves from different gaps has shown that leaves from the youngest gap in the spring contained a statistically lowest quantity of anthocyanin malvidin 3-rutinoside, malvidin 3-glucoside, and peonidin 3-O-neoheseridoside. There were no differences between other locations. For quercetins, it was found that leaves from the youngest gap in the spring contained the highest amount of myricetin-3-rhamnoside. Conclusion is that cyclamen leaves on the youngest gap have not yet completely adapted to increased solar radiation. Quercetins represent first and immediate response to increased UV-B radiation. Leaves on youngest gap in the spring do not yet have sufficient anthocyanin to protect them against radiation. [ABSTRACT FROM AUTHOR]