It is well known that pennycress (
Noccaea praecox
Wulf) hyperaccumulates Cd and Zn and
also accumulates Pb under field conditions. The mai
n purpose of the thesis was therefore to
determine how lead affects the growth and developme
nt of these plants. Plants of pennycress
have been grown for four weeks in basic nutrient so
lution in hydroponics and after one week
1, 10 and 100 μ M of lead was added into separated b
eakers. Two beakers were left with basic
nutrient solution. Hydroponic solution was replaced
weekly. Once per week actual and
potential photochemical efficiency was measured. We
determined fresh and dry mass of roots
and shoots, and from these data the water content w
as calculated. The presence of lead in the
samples was measured by a portable X-ray fluorescen
ce spectrometer. After XRF analysis the
concentrations of photosynthetic pigments were also
determined. From the obtained data we
calculated the average values and displayed results
using graphs. Analyses have confirmed
that various concentrations of lead differently aff
ect the growth and development of plants
and the lead mainly accumulated in roots, but also
in the shoots. The analysis of
photosynthetic pigments showed increased synthesis
of photosynthetic pigments in plants
exposed to 1 and 10 μ M lead. Photochemical efficien
cy of photosystem II did not show
statistically significant differences.
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