0000000000114580
AUTHOR
A. Wessler
Studies on the diurnal courses of the contents of abscisic acid, 1-aminocyclopropane carboxylic acid and its malonyl conjugate in needles of damaged and undamaged spruce trees
Summary The diurnal courses of the contents of 1-aminocyclopropane carboxylic acid (ACC), its malonyl conjugate (MACC) and abscisic acid (ABA) in the two-year-old needles of damaged and undamaged spruce trees (Picea abies L.) were investigated. The contents of ACC and MACC were significantly higher in the needles of the damaged trees as compared with the undamaged ones. In the needles of the damaged spruce trees, the ACC and MACC contents, and ABA contents as well, fluctuated to a greater extent than those in the undamaged spruce trees during the day. The relationships between ACC-ABA and MACC-ACC contents as well are also discussed.
Research on the Diurnal Courses of Abscissic Acid, 1-Aminocyclopropane Carboxylic Acid and Its Malonyl Conjugate Contents in Needles of Damaged and Undamaged Spruces
Ethylene regulates many aspects of plant growth, development and senescence. The immediate precursor of ethylene was identified as 1-aminocyclopropane carboxylic acid (ACC) [7]. Amrhein et al. [1] discovered that ACC supplied exogenously was efficiently converted into ACC malonyl conjugate (MACC) along with ethylene production.
Investigations on the content indole-3-acetic spruce needles of healthy and damaged trees of various sites
Summary Surveys were made on the concentration of indole-3-acetic acid (IAA) in spruce trees of various sites. The concentrations of the hormone were specified with a radioimmunoassay after the needle extract had been purified in several steps. The content of IAA in needles of damaged trees was distinctly lower than the content in needles of healthy trees. Another feature was the annual rythm of the IAA content with the maximum of concentration in June. A distinct diurnal course with highest level of concentration during the early afternoon hours was also observed. The diurnal rhythm of the damaged trees was clearly lower. The supposition is that the lower IAA content is responsible for a p…