الفهرس 
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Abstract
Nowadays, pollution is considered as the most important problem in Egypt, moreover using of mineral fertilizers in agriculture production has resulted in serious problems in the soil and plants. Many solutions were suggested to reduce the previous mentioned problem, so using blue green algae decrease using the mineral form of nitrogen fertilizer. Bioremediation by the use of algal to extract, sequester and/or detoxify pollutants is a new and powerful technique for environmental clean-up. Microalgae received much attention for metal removal due to the cost saving and high adsorption capacity. Microorganisms, including cyanobacteria have been recognized as a cheaper, more effective and an eco-friendly alternative to the conventional physico-chemical remediation methods. Cyanobacteria play an important role in maintenance and build-up of soil fertility, consequently increasing growth and yield as a natural biofertilizer. Cyanobacteria are employed in agriculture as biofertilizers and soil conditioners. The majority of cyanobacteria are capable of fixing atmospheric nitrogen and are effectively used as biofertilizers. cyanobacteria species were recommended to be used as biofertilizers instead of utilizing the expensive industrial chemical fertilizers. This was because of the increased cost of chemical fertilizers that cause soil and water pollution. In comparison, cyanobacteria are a cheap source of N, which does not cause pollution. Thus current study aimed to investigate the influence of different application methods of cyanobacteria on yield, yield quality of broad bean and sorghum plants and bioremediation of agriculture soil from some pollutants.
Two green house experiments were carried out in Agriculture Research Center, Giza, Egypt during two successive winter and summer seasons of 2009 and 2010. Ten cyanobacteria species were isolated from surface layer of soil collected from El-Nubaria village and four species were chosen (Nostoc minutum, Anabaena spiroides ,cylindrosperum marchicum and Nostoc calcicola ) according to their high nitrogenase activity. The planned experiments were carried out to study the interaction among cyanobacteria from one side and soil conditioners on the other side as reflected on growth of broad bean and sorghum plants.
6.1.The first experiment
6.1.1.Effect on growth parameters
Concerning the effect of combined use of biofertilizers with chemical or organic fertilizers application on vegetative growth of broad bean plants. The results showed that the application of( Nostoc minutum, Anabaena spiroides) with organic fertilizers caused increased dry weight and shoot length of broad bean plant whears application of (Nostoc minutum, Anabaena spiroides) with chemical fertilizers showed the lowest values of dry Wt., shoot hight, seed weight and seed No. / plants.
6.1.2.Effect on nutrient content and uptake by broad bean plant.
The highest value of N and P content in broad bean shoots recorded under T2 treatment (100% Nostoc calcicola). It is clearly that the highest mean value of N and K uptake were recorded under (50% cyano. (Nostoc minutum, Anabaena spiroides)) +50% organic compound) treatment. This could be attributed to the effectiveness of the Nostoc minutum, Anabaena spiroides with organic compound in increasing the yield and soil fertility, whears application of (Nostoc minutum, Anabaena spiroides) with chemical fertilizers showed the lowest values of N, P and K uptake in bean plant.
6.1.3.Effect on some heavy metals content and uptake by broad bean plant.
Pb, Cd and Ni contents in shoot, exhibited a highly significant differences between Pb mean values for all treatments, plants supplied with (50% cyano. (Nostoc minutum, Anabaena spiroides)) +50% organic compound) accumulated less Pb concentration in shoots as compared with other treatments and recorded the lowest value of Pb uptake, The lowest value in Ni was recorded in 75% cyano. (Nostoc minutum and Anabaena spiroides)) +50% organic compound. It was observed that the highest value Pb content in bean seeds recorded under T2 followed by T7 over control and the lowest value recorded under T9 whears the highest mean value of Cd content in bean seeds were recorded under T1 followed by T3 but there was no significant differences between other treatments. The mean values of Ni concentration in seed content of bean plant are highly significant under T12 and T8 respectively over control. The highest mean value was recorded under T8 followed by T1 and the lowest value was recorded under T12. It was observed that as the concentration of Pb and Ni in the seeds increased, the seed yield was reduced. It is clearly that the highest mean value of Cd and Ni uptake which accumulated in shoot and seed was found in plants of treatment (T1) followed by T12 whears the lowest mean value of Cd uptake was recorded in T7 and T10 and the lowest value in Ni was recorded in T11 that there is very little differences of uptake mean values of T11 and T7. The uptake of Pb in the shoot and seed of broad bean plant which grown in T3 treatment was the highest value compared to other treatments followed by T8. The lowest value of Pb uptake was recorded under T12 (50% cyano. (Nostoc minutum, Anabaena spiroides)) +50% organic compound) treatment.
6.1.4. Effect of different treatments on soil characters
Soil available nitrogen (N), revealed highly significant differences between treatments. The highest soil N value was observed under T11 and T8 as compared to control treatment and the lowest value was recorded under T12 (50% cyano.(Nostoc minutum + Anabaena spiroides)) +50% organic compound) treatment. Application of (75% cyano.(Nostoc minutum + Anabaena spiroides) + 25% of recommended dose of nitrogen mineral fertilizer (T6) resulted in maximum available P in soil. It was found that the highest mean of soil available K was recorded under the application of (100% Nostoc calcicola) (T2) over control. Data showed that the soil pH tended to decrease slightly due to the application of compost and biofertilizer. Generally, the pH of the soil after harvesting was lower than that recorded before planting. It was observed that soil salinity (EC) value after cultivation and application of cyanobacteria with chemical or organic fertilizers was lower than EC value before experiment. It is clear that the lowest mean value of available lead was found under T3 (75% Nostoc calcicola +25% chemical fertilizers) whears, the lowest Ni value was recorded by T10. (50% Nostoc calcicola +50% organic compound).
6.2.The second experiment
6.2.1.Effect on growth parameters
Combined use of biofertilizers with chemical or organic fertilizers application improved the growth of sorghum plant indicated by plant length and total dryweight. The results showed that the application of biofertilizer in combination with organic fertilizers caused increased vegetative growth of sorghum when compared to control. plant height was affected by application of both biofertilizer and organic fertilizer. Maximum plant length was recorded under (50% cyano. (cylindrosperum marchicum + Anabaena spiroides)) +50% organic compound) treatment followed by 100% chemical fertilizer treatment.
6.2.2.Effect on nutrient content ,uptake by broad bean plant and heavy metal contents in shoot.
Results showed that T1 (100% chemical fertilizers) recorded the highest mean value of nitrogen content in sorghum shoot followed by T11 (50% (Cylindrosperum marchicum + Nostoc calcicola) + 50% organic compound). T2 (100% cyano. (Nostoc calcicola + Anabaena spiroides)) recorded the highest mean value of phosphrous content in sorghum shoot, while potassium showed significant differences between mean values for all treatment. The highest K concentration was observed at T8 (100% Organic compound). It is clearly that the highest mean value of N and K uptake were recorded under T1 (recommended dose of nitrogen mineral fertilizer) application, followed by T13 (50% (Nostoc calcicola + Anabaena spiroides) + 50% organic compound) treatment in N uptake and T14 (75% (Anabaena spiroides + Cylindrosperum marchicum +25% organic compound) treatment in K uptake. Maximum mean value of phosphorus uptake was recorded with T2 (100% cyano. (Nostoc calcicola + Anabaena spiroides)). The lowest mean value was recorded under T14 (75% (Anabaena spiroides + Cylindrosperum marchicum) +25% organic compound) whears the lowest mean value was under T13 (50% (Anabaena spiroides + Nostoc calcicola) + 50% organic compound). On the other hand, plants supplied with (100% Anabaena spiroides + Nostoc calcicola) species treatment accumulated less Pb and Ni in shoots of sorghum plant.
6.2.3. Effect of different treatments on soil characters
Data showed that the amounts of some available N, P and K (mg/kg) in soil cultivated with sorghum as affected by different treatments. In general the available N, P and K in soil after sorghum harvest were significantly influenced by biofertilizer combinations with chemical or organic fertilizers application. The highest soil N and P value recorded under T4 (50% Anabaena spiroides + Nostoc calcicola +50% chemical fertilizers). It was found that soil available K influenced by different treatments that soil available K increased under T4 (50% Anabaena spiroides + Nostoc calcicola + 50% chemical fertilizers) over control. Data showed that the soil pH tended to decrease slightly due to application of compost and biofertilizer. On the other hand, the soil pH, after the two seasons, tended to increased slightly with increasing the N mineral fertilizer rates combined with biofertilizer. The lowest mean values of available lead and Ni in soil were recorded under T6 (75% Anabaena spiroides + Cylindrosperum marchicum +25% chemical fertilizers).