0000000000759271
AUTHOR
S. Tietz
Phosphoenolpyruvate Carboxylase Activity and Malate Content of Spruce Needles of Healthy and Damaged Trees at Three Mountain Sites
Summary Investigations were carried out on the phosphoenolpyruvate carboxylase (PEPC) activity and the malate content in spruce trees [Picea abies (L.) Karst] at three natural sites. In needles of damaged spruce the PEPC activity is significantly higher than in needles of undamaged spruce. Therefore, the PEPC activity seems to be a biochemical damage indicator in spruce needles. The increase in PEPC activity in damaged trees is discussed as a repair mechanism to compensate the increased need of carbon skeletons by providing oxaloacetate. The malate content is enhanced in needles of severely damaged trees. An increase in malate seems to indicate senescence reactions and may be related to the…
Investigations on the phosphoenolpyruvate carboxylase activity of spruce needles relative to the occurrence of novel forest decline
Summary 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 d…