Influence of refertilization of Salix cinerea L. in late summer on early frost hardiness and on some nutrients and biomarker. [German]Original Title Auswirkungen einer Nachdungung im Sommer auf die Frostharte von Salix cinerea L. sowie auf ausgewahlte Nahrstoffe und Biomarker.

摘要

One year old rooted cuttings were fertilized with Osmocote exact according to 0,8 g N L-1 substrate in February 2009. In August half of the plants received the same fertilizer dose while the other half was not refertilized. In autumn 2009 and in spring 2010 early resp. late frost tests were carried out under controlled conditions, furthermore sprouting was evaluated in spring 2010. Frost damage was measured with the electrolyte leakage method. In the early frost test biochemical stress responses like glucose, sucrose and proline were analyzed. In the new shoots N-, P-, and K-concentration were measured. Refertilized plants did not grow more but showed higher N-, P-, and K-concentrations. These plants had more proline in their buds and roots compared to the non-refertilized ones. Sucrose and glucose contents in the roots of refertilized plants were lower than in non-refertilized ones, in the buds there was no difference. Damage due to early frost was independent from refertilization for new shoots and buds but in roots higher for the refertilized plants. In spring 2010 refertilized plants sprouted earlier compared to non-refertilized ones. In buds damage due to late frost slightly increased in refertilized plants while in roots there was no difference between the fertilization treatments.