الفهرس 
Effect on chemical contents
Fresh weightOnly 14 pages are availabe for public view
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Abstract
Fertilization is one of the most important factors limiting the productivity of plants. The intensive use of expensive mineral fertilizers in recent years resulted in environmental pollution problems.
Chemical fertilizers at extremely high rates for a long period decreased the potential activity of microflora and the stability of soil organic matter, Pokorna (1984).
Biofertilizers are produced and practiced in different counlries äs well äs in Egypt, they are either nitrogen fixers (Rhizobia, Azotobacter, Azospirillum and Algae) or phosphate solubilizing microorganisms (Bacteria and Mycorrhiza). Utilized biofertilizers could supply plants with their needs of nitrogen and phosphorus during their growth by cheap means, which in turn decreases, the application of expensive mineral fertilizers and lead to significant decrease in production costs of the different crops. In addition pollution rates in soil, water and air could be Iowered äs a result of decreasing the extensive using of chemical fertilizers. Alaa El-Din (1982) and Osman etal (1992).