الفهرس 
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Abstract
Pot experiments were carried out in Faculty of Agriculture, Shibin EI-Kom, Minufiya University during the two growing summer seasons of 2009 – 2010. This experiment to study:
1- The phytoremediation by some hyperaccumulator plants (Genotypes)
[sunflower (Helianthus annuus L. cv. Miac), cowpea (Vigna unguiculata
L.) and cockscomb (Celosia cristata L.)].
2- Studying uptake of lead and cadmium from the soil supplemented with
those metals separately, and determine the metal translocation from
different plant parts.
3- Observation the effects of heavy metals on the growth, physiological,
biochemical, internal structure and yield of aforementioned crops during
the experiment period.
4- Select the better hyperaccumulator plant to be used for
phytoremediation.
The soil was polluted by different concentrations of heavy metals
such as lead (Pb) at levels 0, 50, 100, 200, 400, 800 and 1600 mg / kg soil
and cadmium (Cd) at levels 0, 10, 20, 40, 80, 160 and 320 mg / kg soil as
alone. Genotypes samples were taken after 40 and 60 days from sowing.
During the crops accumulate the heavy metals from polluted soil these
aspects were studied: Growth characters, some physiological and
biochemical aspects, i.e photosynthetic pigments, water relations, total
carbohydrates and total sugars, proline, activity of some enzymes, total
protein, some mineral compositions, the accumulation of heavy metals in
different plant parts, endogenous phytohormones, internal structure of
different plant parts of all crops as well as yield and its attributes of all
plants.
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The obtained results could be summarized in the following:
Growth characters:
1. The vegetative growth characters: in items, root length, plant height,
leaves number, leaf area, relative growth rate, net assimilation rate, fresh
and dry weight of roots, shoots and whole plant of sunflower, cowpea and
cockscomb were significantly decreased with increasing the accumulation
of Pb metal inside the different crops at all levels of Pb.
2. The characters: root length, plant height, leaves number, leaf area, relative
growth rate, net assimilation rate, fresh and dry weight of root, shoot and
whole plant, were significant decreases with increasing the Cd
concentrations in plant tissues.
Water relations:
3. With increasing the Pb accumulation by tested crops a positive effect
occurred on bound water, bound / free water ratio, leaf water deficit and
osmotic pressure of leaves of sunflower, cowpea and cockscomb,
meanwhile had a negative effect on total water content, free water,
relative water content and transpiration rate.
4. The bound water, bound / free water, leaf water deficit and osmotic
pressure increased with increasing the Cd concentrations inside plant
parts, whereas total water content, free water, relative water content and
transpiration rate were decreased under the same conditions.
Photosyntheic pigments
5. The concentrations of chI. a, chI. b, chI. a + b and carotenoids in leaves
were significantly decreased at Pb contamination from 50 to 1600mg / kg
soil, meanwhile the ratios of chI. a / b and chI. a + b / carotenoids
recorded a significant increase.
6. The accumulation of Cd inside tested genotypes caused a decrease in chI.
a, chI. b, chI. a + b and carotenoids, and increased the ratios of chI. a / b
and chI. a + b / carotenoids.
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Total carbohydrates and total sugars:
7. The concentrations of both total carbohydrates and total sugars in leaves,
of genotypes we are used were decreased with increasing Pb
concentrations in the plant tissue.
8. Increasing Cd concentrations in the plant tissue showed a significant
decrease in the concentrations of total carbohydrates as well as the total
sugars.
The proline concentration:
9. The proline content in leaves was increased with increasing the
accumulation of Pb inside the plant tissue as compared with the control.
10. The concentration of proline in leaves was significantly increased with
increasing Cd concentrations inside the plant tissue.
Activity of some enzymes:
11. The increase of Pb accumulation inside tested genotypes led to increase
in the peroxidase activity as well as phenoloxidase activity.
12. The activity of peroxidase and phenoloxidase in leaves was increased
with increasing the concentrations of Cd inside tested genotypes.
Mineral statues:
13. The accumulation of Pb in different plant organs led to decrease of N, P
and K concentrations in root, stem and leaves of sunflower, cowpea and
cockscomb genotypes.
14. Cd accumulation in different plant organs caused a reduction in N, P and
K concentrations in different plant organs.
The accumulation of heavy metals (Pb & Cd):
15. The accumulation of Pb inside different plant organs of tested crops
increased with increasing the soil contamination with Pb and the time
period. Cockscomb was the most accumulators crop to Pb as well as the
roots of crops was the most organs in accumulation.
16. The increase of Cd levels in soil led to increase the Cd concentrations in