الفهرس 
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Abstract
This study was focused on
The role of Azolla pinnata in accumulation of different pollutants
such as heavy metals (Pb+2, Co+2 and Cu+2) existing in agricultural
wastewater to select the most effective plant for treating polluted
agricultural wastewater. The growth density, fresh and dry weight,
doubling time of A. pinnata and its accumulation of different
concentrations of these heavy metals were traced during a period of 25
days. Using different concentration of agricultural wastewater for
irrigation of rice and wheat crops were also studied with the inoculation
of Azolla pinnata and/or Pseudomonas fluorescens.
1- Estimation the growth yield of Azolla pinnata in three different
media
This experiment was conducted to estimate the ability of A.
pinnata to grow on different media. A. pinnata was inoculated in three
different media namely Yoshida, peat moss and Soil media to select the
best growth medium by measuring fresh and dry weight, doubling time,
NPK content and Nitrogenase activity.
The highest fresh and dry weight was recorded within Yoshida
medium after 25 days from inoculation compared to Peat moss and Soil
media being 25.38 and 1.69 g/ pot fresh and dry weight, respectively.
The lowest doubling time was recorded with Yoshida medium
being 5.36 days.
The maximum nitrogenase activity was recorded after 20 days
from inoculating Azolla pinnata in all of the three media. While the
highest increase in nitrogenase activity was recorded within Azolla
pinnata grown in Yoshida medium after 20 days being 13.29 (μ mol
C2H4/g dr. wt./h.)
The highest NPK% was recorded within Yoshida medium after 25
days from inoculation being 3.87, 0.58 and 1.59% respectively.
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SUMMARY AND CONCLUSION
Rabab Rahmy Hanafy (2017), M.Sc., Fac. Agric., Ain Shams Univ.
The results of this experiment validate that Yoshida medium is
considered the preferable medium for the best performance of Azolla
pinnata.
2- Estimation the growth yield of A. pinnata in Yoshida medium
supplemented with different heavy metals
This experiment was designed to estimate the ability of Azolla
pinnata to grow on Yoshida medium supplemented with different
concentrations from heavy metals (Pb++, Co++ and Cu++) separately.
Lead Pb+2
The highest significant fresh and dry weight were recorded within
Azolla pinnata inoculated in Yoshida medium treated with Pb+2 35 mg/L.
after 20 days from inoculation, being 9.5 and 0.57 g/pot respectively.
The lowest doubling time was recorded within Azolla pinnata
inoculated in Yoshida medium that contains 35 mg/L., after 20 days from
incubation being 6.17days.
Cobalt Co+2
The highest significant fresh weight was recorded within Azolla
pinnata inoculated in Yoshida treated with 15 mg/L. Co+2 after 20 days
from inoculation, being (9.8 g/pot). While The highest significant dry
weight was recorded with Azolla pinnata inoculated on Yoshida medium
treated with 35mg/L., after 20 days from inoculation being (0.72 g/pot).
The lowest doubling time was observed within Azolla pinnata
inoculated in Yoshida medium that contains 25 mg/L. from Co+2, being
(6.07 day).
Copper Cu+2
The highest significant increase in fresh weight was recorded
within Azolla pinnata cultivated in Yoshida supplemented with 15 mg
Cu+2/L. after 20 days being 5.36 (g/pot). While the highest significant
82
SUMMARY AND CONCLUSION
Rabab Rahmy Hanafy (2017), M.Sc., Fac. Agric., Ain Shams Univ.
increase in dry weight was recorded within Azolla pinnata inoculated in
yoshida medium supplemented with 5 mg Cu+2/L being 0.43 (g/pot).
After 20 days from the inoculation of Azolla pinnata in the
medium at which Azolla pinnata revealed the highest significant fresh and
dry weight, the lowest doubling time was recorded within Azolla pinnata
inoculated in Yoshida medium that contains 5mg/L. from Cu+2, being
8.26 days.
Exposing Azolla pinnata to heavy metals suppressed their
vegetative growth and sporulation and the suppression percentage
depends on the species and the concentration of heavy metals.
3- Estimation the capability of Azolla pinnata to grow and
phytoremediate agricultural wastewaters contaminated with
different heavy metals (Pb++, Co++ or Cu++)
In this investigation, three types of Agricultural wastewaters
contaminated with (Pb++, Co++ or Cu++) were used to evaluate the
capability of Azolla pinnata to grow on different heavy metals.
Different dilutions from agricultural wastewaters contaminated by
different heavy metals were used to examine the ability of Azolla pinnata
to grow and tolerate different concentrations from heavy metals as well as
its potentiality to accumulate these metals in the tissue during incubation
period (25 da ys).
Lead Pb+2
The highest significant fresh and dry weight of Azolla pinnata
were recorded within the treatment that contains 75% agricultural
wastewater and 25% tap water after 25 days from inoculation being 11.19
and 0.73 (g/pot) respectively.
The lowest doubling time was recorded within Azolla pinnata
inoculated on 75% agricultural wastewater during all incubation periods
being 2.17, 3.56, 4.96, 5.96 and 7.17days respectively.
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SUMMARY AND CONCLUSION
Rabab Rahmy Hanafy (2017), M.Sc., Fac. Agric., Ain Shams Univ.
The highest N, P and K % were recorded within Azolla pinnata
grown in 75% agricultural wastewater after 25 days of incubation being
3.35%, 0.80% and 2.75% respectively.
The highest concentrations of Pb+2 were recorded in Azolla
pinnata cultivated in 100% agricultural wastewater during all incubation
periods being 9.52, 10.96, 14.26, 14.95 and 15.79 mg/pot respectively.
While the lowest concentrations of Pb+2 were recorded in Azolla pinnata
cultivated in 25% agricultural wastewater during all incubation periods
being 2.79, 3.07, 3.35, 3.57 and 3.81 mg/pot respectively.
Cobalt Co+2
The highest significant fresh and dry weight were recorded within
Azolla pinnata inoculated on the 75% agricultural wastewater after 25
days of incubation being 10.89 and 0.73 (g/pot) respectively.
The lowest value in the doubling time was recorded within the
treatment 75% agricultural wastewater during all the incubation period
being 2.22, 3.56, 4.71, 6.01 and 7.25 day respectively.
The highest N, P and K % were recorded within Azolla pinnata
grown in 75% agricultural wastewater after 25 days from inoculation
being 3.39%, 0.69% and 2.69% respectively.
The highest concentrations of Co+2 were recorded in Azolla
pinnata cultivated in 100% agricultural wastewater during all incubation
periods i.e 5, 10, 15, 20, 25 days being 11.72, 12.97, 13.99, 14.81 and
16.97 mg/pot respectively. While the lowest concentrations of Co+2 were
recorded in Azolla pinnata cultivated in 25% agricultural wastewater
during all incubation periods being 1.64, 1.89, 1.98, 2.19 and 2.58 mg/pot
respectively.
Copper Cu+2
The highest significant fresh and dry weight were recorded within
Azolla pinnata inoculated on 75% agricultural wastewater after 25 days
from incubation being 11.2 and 0.73 (g/pot) respectively.
84
SUMMARY AND CONCLUSION
Rabab Rahmy Hanafy (2017), M.Sc., Fac. Agric., Ain Shams Univ.
The lowest doubling time was recorded within Azolla pinnata
cultivated on 75% agricultural wastewater during all inoculation period
being 2.58, 4.21, 4.90, 6.00 and 7.25 day respectively.
The highest N, P and K % were recorded within Azolla pinnata
grown in 75% agricultural wastewater after 25 days of inoculation being
3.31%, 1.69% and 2.71% respectively.
The highest concentrations of Cu+2 were recorded in Azolla
pinnata cultivated in 100% agricultural wastewater during all incubation
periods being 12.62, 13.88, 15.43, 17.11 and 19.33 mg/pot respectively.
While the lowest concentrations of Cu+2 were recorded in Azolla pinnata
cultivated in 25% agricultural wastewater during all incubation periods
being 1.24, 1.33, 1.55, 2.07 and 3.25 mg/pot respectively.
This experiment focused on the role of Azolla pinnata in the
removal of different heavy metals from agricultural wastewater. The
response of Azolla pinnata to the presence of different concentration from
agricultural wastewater was variable in accordance to the different
treatments in all growth parameters as well as the percentage of heavy
metals accumulated in Azolla pinnata.
4- Rice plants irrigated with different concentrations from
contaminated agricultural wastewater and inoculated with Azolla
pinnata and/or Pseudomonas fluorescens
High increase in plant height (cm), grain yield (g/pot) and straw
yield (g/pot) were recorded within rice plants irrigated by 75%
agricultural wastewater as sub treatments in all treatments (Azolla
pinnata, Azolla pinnata + Pseudomonas fluorescens and Pseudomonas
fluorescens). While by comparing all treatments and sub treatments
together, the highest significant increase in the growth parameters of rice
plants were recorded within plants irrigated by 75% agricultural
wastewater and inoculated with Azolla pinnata + Pseudomonas
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SUMMARY AND CONCLUSION
Rabab Rahmy Hanafy (2017), M.Sc., Fac. Agric., Ain Shams Univ.
fluorescens being 97.85 (cm), 29.40 (g/pot) and 26.90 (g/pot)
respectively.
High increase of NPK% in grain and straw was recorded within
plants irrigated with 75% agricultural wastewater as sub treatment in all
treatments (Azolla pinnata, Azolla pinnata + Pseudomonas fluorescens or
Pseudomonas fluorescens). While by comparing all treatment and sub
treatments together, the highest significant increase in NPK% was
recorded within plants irrigated with 75% agricultural wastewater and
inoculated with Azolla pinnata + Pseudomonas fluorescens, being 1.62,
2.29 and 1.10% in grain and 0.73, 0.52 and 1.97% in straw respectively.
The highest significant increase of Pb, Co and Cu in both grain
and straw were recorded within plants irrigated with 100% agricultural
wastewater as a sub treatment in all treatments (Azolla pinnata, Azolla
pinnata + Pseudomonas fluorescens or Pseudomonas fluorescens). While
the lowest significant concentration in (Pb, Co and Cu) were recorded in
plants irrigated with 25% agricultural wastewater and inoculated with
Azolla pinnata and Pseudomonas fluorescens, being 0.01, 0.01, 0.02 mg/g
dry weight in grain and 0.02, 0.01 and 0.03 mg/g dry weight in straw
respectively.
Wheat plant irrigated with different concentrations from
contaminated agricultural wastewater and inoculated with Azolla
pinnata and/or Pseudomonas fluorescens
High increase in plant height (cm), grain yield (g/pot) and straw
yield (g/pot) were recorded within wheat plants irrigated by 75%
agricultural wastewater as sub treatments in all treatments (Azolla
pinnata, Azolla pinnata + Pseudomonas fluorescens or Pseudomonas
fluorescens). While by comparing all treatments and sub treatments
together, the highest significant increase in the growth parameters of
wheat were recorded within plants irrigated by 75% agricultural
wastewater and inoculated with Azolla pinnata+ Pseudomonas
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SUMMARY AND CONCLUSION
Rabab Rahmy Hanafy (2017), M.Sc., Fac. Agric., Ain Shams Univ.
fluorescens, being 93.30 (cm), 31.96 (g/pot) and 26.67 (g/pot)
respectively.
High increase in NPK% in grain and straw were recorded within
plants irrigated with 75% agricultural wastewater as sub treatment in all
treatments (Azolla pinnata, Azolla pinnata + Pseudomonas fluorescens or
Pseudomonas fluorescens). While by comparing all treatment and sub
treatments together the highest significant increase in NPK% were
recorded within plants irrigated with 75% agricultural wastewater and
inoculated with Azolla pinnata + Pseudomonas fluorescens together,
being 1.95, 0.91 and 2.10% in grain and 0.85, 0.55 and 1.93% in straw
respectively.
The highest significant increase in Pb, Co and Cu in both grain
and straw were recorded within plants irrigated with 100% agricultural
wastewater as a sub treatment in all treatments (Azolla pinnata, Azolla
pinnata + Pseudomonas fluorescens or Pseudomonas fluorescens). While
the lowest significant concentration from (Pb, Co and Cu) were recorded
in plants irrigated with 25% agricultural wastewater and inoculated with
Azolla pinnata and Pseudomonas fluorescens being 0.11, 0.09, 0.22 mg/g
dry weight of grain and 0.13, 0.12, 0.29 mg/g dry weight of straw
respectively.
CONCLUSION
The best selective medium to grow A. pinnata is Yoshida medium
as compared to Peat moss and Soil media.
A. pinnata can tolerate the growth on media with different heavy
metals (Pb+2, Co+2 & Cu+2) with different concentration.
The concentrations from 5 to 35 ppm of heavy metals increase
fresh and dry weights of Azolla and decrease the doubling time, but in 45
ppm the fresh, dry weights was decreased and doubling time was
increased.
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SUMMARY AND CONCLUSION
Rabab Rahmy Hanafy (2017), M.Sc., Fac. Agric., Ain Shams Univ.
Azolla has potentiality to grow safely on 75% agricultural
wastewater polluted with (Pb+2, Co+2 and Cu+2) at dilution rate 75%
agricultural wastewater to 25% tap water.
A. pinnata could be used as phytoremediator to accumulate heavy
metals from polluted water, the fresh and dry weight were increased from
25% to 75% of agricultural wastewater and doubling time was decreased
but in 100% agricultural wastewater fresh and dry weight was decreased
and doubling time was increased.
After that, agricultural wastewater could be used to irrigate
economic crops (rice& wheat) to test if heavy metals moved to the plants
or not by using group I: Azolla pinnata, group II: Pseudomonas
fluorescens, group III: Azolla pinnata+ Pseudomonas fluorescens.
The results recorded a highest significant with group III Azolla
pinnata+ Pseudomonas fluorescens that recorded highest growth
parameters of plants and lowest trace of heavy metals in the economic
plants.
The free floating macrophyte has successfully removed the metals,
without production of any toxicity.
A. pinnata is a potential candidate for accumulation of heavy metals from
polluted water. Overall, the results showed that, A. pinnata could be used
in heavy metal bioremediation from agricultural wastewater, representing
an effective, eco-friendly and low cost treatment technology