A pot study was conducted to investigate the potential of alfalfa for phytoremediation of soil artificially contaminated with different concentrations of Pb and Cd and their combinations. Harvested plants were divided and used for two purposes: (1) separation into roots and shoots, which were digested to determine N, P, K, Pb and Cd concentrations, and (2) the use of fresh shoots to prepare alfalfa extract representing each treatment. Subsequently, lettuce seedlings were grown in the same pots with the same soil and without adding fertilizers; the alfalfa shoot extract prepared from each treatment was added to the treatment itself. Lettuce crops harvested after 67 days from transplanting were divided into roots and shoots which were digested to determine the previously studied elements. In addition, soil samples were collected after harvesting alfalfa and lettuce plants and prepared for chemical analyses. Results showed that alfalfa is an effective accumulator plant for the phytoremediation of Pb- and Cd-contaminated soils. In addition, using the alfalfa shoot extract to fertilize lettuce crops was beneficial to their growth without any risk of translocation of heavy metals. Thus, we recommend adding alfalfa to crop rotations, especially where soils are contaminated with heavy metals.

Natural sources of water are limited in Egypt. The rapidly growing populations necessitate continuous expansion of the cultivated area. This means an increase of the gap between the demands of water for irrigation and the limited water supply. Looking for other sources such as low quality water like (industrial effluent, drainage and sewage) must be used in irrigation of some garden and wood plants. This investigation was conducted on agricultural drainage wastewater from El Mohete drain (Marioteya Canal) west of Cairo; the samples were collected from different places during (Summer and Winter seasons). The wastewater contaminated with pathogenic microorganisms, the excess of fertilizers (inorganic & organic), heavy metals, and the residuals of pesticides. Plant Growth Promoting Rhizobacteria (PGPR) could remediate the wastewater as biological bioremediation to remove some pollutants such as pathogenic microorganisms, heavy metals and pesticides. Chemical remediation was used as nitrification inhibitor to stop transformation of ammonia to nitrate. This work was conducted to study the ability of PGPR strains e.g. Bacillus megaterium, Bacillus subtillis, Bacillus circulans, Paenibacillus polymyxa, Pseudomonas floresense, Serratia sp. and Azotobacter chroococcum 5, 9 and 23 to treat the drainage water for irrigation the Mentha viridis cv. and Gladiolas grandiflorus cv. plants.                 Two pot experiments were conducted in greenhouse. The treatments were applied as follows; Natural water, treated water and drainage water to irrigate the plant. Use the PGPR as inoculants and thiourea as nitrification inhibitor, Heavy metal treated was (Copper, Cobalt, Zinc, Cadmium and Mercury) the result showed us heavy metals removal by PGPR from drainage water. The characterizations of PGPRs as shown in the obtained results are they could enhance plant growth by using their own metabolism (solublizing phosphate, producing hormones or fixing nitrogen) as well as correlation of them with the potenit of effects on the growth of plants in unfavorable conditions in order to improve the efficiency of phytoremdiation of contarinated soils. The removal of heavy metals and the elimination of pesticides residues were markedly noticed in this investigation. Results also confirmed the ability of PGPRs in suppressing the effect of pathogenic bacteria like Salmonellasp and E.coli. These abilities are of great importance in terms of plant and soil health. Consequently, the role of PGPRs bacteria associated with plant rhizosphere in remediation of water and soil contaminations due to its biochemical activity and thus, stimulate plant growth is a great important subject in phytoremediation process nowadays.

A pot study was conducted to investigate the potential of alfalfa for phytoremediation of soil artificially contaminated with different concentrations of Pb and Cd and their combinations. Harvested plants were divided and used for two purposes: (1) separation into roots and shoots, which were digested to determine N, P, K, Pb and Cd concentrations, and (2) the use of fresh shoots to prepare alfalfa extract representing each treatment. Subsequently, lettuce seedlings were grown in the same pots with the same soil and without adding fertilizers; the alfalfa shoot extract prepared from each treatment was added to the treatment itself. Lettuce crops harvested after 67 days from transplanting were divided into roots and shoots which were digested to determine the previously studied elements. In addition, soil samples were collected after harvesting alfalfa and lettuce plants and prepared for chemical analyses. Results showed that alfalfa is an effective accumulator plant for the phytoremediation of Pb- and Cd-contaminated soils. In addition, using the alfalfa shoot extract to fertilize lettuce crops was beneficial to their growth without any risk of translocation of heavy metals. Thus, we recommend adding alfalfa to crop rotations, especially where soils are contaminated with heavy metals.

Azolla pinnata is a small aquatic fern which considered as a multipurpose organism. It isused in bioremediation to remove heavy metals from polluted draining waters. In view of its potentiality, Azolla pinnata were tested for their growth on different media (Yoshida, peat moss, and Soil media) to select the best medium for the growth of Azolla. Then the best medium was examined for the potentiality of Azolla to withstand a different concentration of different heavy metals. Yoshida medium was the most suitable medium, as it recorded the highest significant records in fresh and dry weight, being 25.38 and 1.69 g/ pot respectively, the doubling time was 5.43 days, NPK% being 3.87, 0.85 and 1.95% respectively and nitrogenase activity being 14.32 μmol C2H4/ g dry weight. / hr). The fresh and dry weight of Azolla exposed to Pb+2,Co+2 or Cu+2, was found to be increased by increasing the concentration of the metals from 5 to 35 ppm/liter, then they decreased when the fern exposed to 45 ppm/liter for all of them. While, doubling time decreased gradually by increasing the concentration of Pb+2 , Co+2  orCu+2 from 5 to 35 ppm/liter and started to increase by increasing the concentration of Pb+2 to 45 ppm/liter in the medium.

Phytoextraction of heavy metal from contaminated soils is promising remediation technology.  In the present study, hyper-accumulator plants, indian mustard (Brassica juncea.( L) czern) and ryegrass (Lolium multiflorum Lam) have been used to remove the excess undesirable concentrations of zinc and copper from contaminated soil. Zinc and copper uptake have been enhanced by adding EDTA to the contaminated soil using two concentrations (2.5 and 7.5 mmol/Kg soil). Accumulation of Zn by the indian mustard shoots and roots under the effect of EDTA recorded 4 to 6 times as adsorbed by the control while less enhancement of Zn uptake was recorded by the ryegrass shoots and roots. On the other hand, Cu accumulation showed significant enhancing by the ryegrass shoot comparing to the indian mustard shoot at the both employed EDTA concentrations. The ryegrass roots gave enhanced Cu uptake at the EDTA conc. 7.5 mmol/Kg soil only while the indian mustard roots recorded an increasing in the Cu-uptake with the two EDTA concentrations