Neuartige Waldschäden

Polyamines accumulate under various stress conditions in leaves of herbaceous plants. These stress responses, which are related to the physiological functions of polyamines, notably theirmembrane-stabilizing andradical-scavanging effect, are protective measures taken by the plant. Results from several natural spruce stands in Germany indicate that putrescine levels depend on the extent of damage. Needles with early signs of damage and needles with severe damage had significantly higher levels of putrescine than needles of healthy trees. Long-term fumigation of young beech and spruce trees with high concentrations of ozone, SO₂, and NO_x shows elevated levels of putrescine in leaves and needles. Thus, putrescine content can be used as a stress indicator in the assessment of novel forest damage even at early stages.