PROCEEDINGS: Index of Abstracts
PUTRESCINE: A MARKER OF STRESS IN RED SPRUCE TREES
1-USDA Forest Service, Northeastern Forest
Experiment Station, PO Box 640, Durham, NH 03824. 2-Research Hydrologist,
US Geological Survey, 425 Jordan Rd., Troy, NY 12180. 3-University
of Illinois, W-503 Turner Hall, 1102 S. Goodwin Ave., Urbana, IL
61801. 4-University of New Hampshire, Plant Biology Department,
Durham, NH 03824.
Aluminum (Al) has been suggested to be an important stress factor
in forest decline due to its mobilization in soil following atmospheric
deposition of acidic pollutants. A major goal of our research is
to develop physiological and biochemical markers of stress in trees
using cell cultures and whole plants. Needles of red spruce (Picea
rubens) collected from several sites in the northeastern United
States and red spruce cells grown in suspension cultures were examined
for polyamine and inorganic-ion content. The cells in culture were
exposed to various concentrations of Al for different lengths of
time. Exposure to Al increased putrescine biosynthesis and lowered
the concentrations of cellular Ca, Mg, Mn, and K. No treatments
were applied to the trees but some of the sites were known to be
under "general environmental stress" as indicated by a
large number of dead and dying red spruce trees. All of the sites,
while differing in geochemistry, had a soil pH value below 4.0.
Data collected from field studies enabled us to categorize these
sites on the basis of cellular levels of putrescine and soil chemistry.
Needles from trees growing on Ca-rich soils (organic horizon) with
low exchangeable Al:Ca ratios had lower levels of putrescine than
those from trees growing on Ca-poor soils with high Al:Ca ratios.