Investigations on the Phosphoenolpyruvate Carboxylase Activity of Spruce Needles Relative to the Occurrence of Novel Forest Decline

1991

4 Abb., 1 Tab., 25 Lit. Ang.

Unselbständiges Werk

5818

200050582

Investigations were carried out on phosphoenolpyruvate carboxylase (PEPC) activity in needles of Norway spruce trees (Picea abies (L.) Karst.) at two natural sites during the course of three vegetation periods. PEPC activity found in needles of damaged trees was considerably higher than in needles of undamaged trees. Annual average figures varied up to 100%. The positive correlation between PEPC activity and the extent of damage of the investigated needles indicates a significant relationship between both parameters: the PEPC activity in spruce needles seems to be not only a qualitative, but also a quantitative indicator of the extent of damage. Higher PEPC activity in needles of damaged spruce trees are interpreted as a mechanism to replenish the tricarboxylic acid cycle intermediates through the formation of oxaloacetate.