This study was carried out to investigate the alleviation of salt stress (0, 6.25, 12.50 and 25 dS/m) on growth and development of Acacia saligna, grown in sandy loam sterile soil by using arbuscular mycorrhizal fungi (AMF) and Sinorhizobium terangae (R), individually or in combination (AMF+R). Growth and nodulation parameters, leaf osmotic adjustment and chemical analysis were used as parameters. Salt stress increases the percentage of sodium (Na) and calcium (Ca) contents as well as proline; meanwhile, it reduces the leaf osmotic potential, growth parameters, nodulation parameters, Nitrogen, phosphorus, potassium (N. P. K.) contents, total carbohydrates percentages and chlorophyll contents. Co-inoculated (AMF+R) stressed plants were able to maintain a higher osmotic potential of cells leading to the significantly rapid growth, enhanced nodulation parameters, N, P, K, Ca, total carbohydrates percentages and chlorophyll contents as well as proline in leaves, and significantly reduced the Na percentage. In conclusion, Co-inoculated (AMF+R) enabled the plants to maintain osmotic adjustments and enhanced the plants tolerance against salinity.

A field experiment was carried out in sandy soil at El-Ismailia Agricultural Research Station, El-Ismailia Governorate, Agricultural Research Center (ARC) to study the effect of treating the soil with different types of compost (plant residues with organic manure and plant residues with cellulose decomposers), (AM)-mycorrhizae and N2-fixing bacteria on the growth and yield of wheat plants. Plant dry weight recorded a significant increase when the soil was treated with compost provided with cellulose decomposers and biofertilizers. The highest number of tillers obtained with compost B amended with organic manure and biofertilizers.The maximum infection percentage was due to compost A provided with organic manure. The optimum nitrogenase enzyme activity obtained when the soil was treated with compost B plus cellulose decomposers and biofertilization. High significant nitrogen percentage was shown when the soil was amended with compost D + organic manure + biofertilizers. Inoculation with N2-fixers + (AM) mycorrhizae led to the increase of phosphorus % and this was clearly obtained with compost "B" plus cellulose decomposers. Inoculation with mixed diazotrophs + (AM)-mycorrhizae increased potassium % and this was obtained with compost D plus organic manure at the period of 45 days from sowing.Results showed significant increases in yield parameters, i.e., 1000-grain weight, grain yield and straw yield. The addition of compost B amended with organic manure + N2-fixers + (AM) mycorrhizal gave the superior yield. Generally, it was remarkable that the essential role of organic matter represented in compost, N2-fixers and (AM) mycorrhizae in enhancing the growth and yield of wheat.

Two field experiments were conducted in a calcareous soil at El-Noubaria Research Station (ARC) during two successive seasons (2006 and 2007) to study the effect of biofertilizer inoculation with nitrogen fixing bacteria (Azospirillum lipoferum, Azotobacter chrococcoum, Bacillus polymyxa and Klebsiella pneumoniae), Ksolubilizing bacteria (Bacillus circulans) and Arbuscular mycorrhizal fungi on growth, yield and different storage periods of onion (Allium cepa) cultivar Giza 20. The important obtained results are as follows: Plant height and number of tubular leaves, plant dry weight and yield as growth parameters, nitrogenase enzyme activity, dehydrogenase enzyme activity and the percentage of AM-mycorrhizal infection as microbiological parameters and total nitrogen, phosphorus, potassium and carbohydrates as chemical parameters gave more vigor growth and yield due to the inoculation with N2-fixers + Bacillus circulans + AM-mycorrhizae + ½ dose of NPK fertilizers compared to control during both tested seasons and that also they recorded best plant growth, harvest bulbs yield (12.7 and 13.7 ton/fed), onion chemical properties as well as increased the tolerance against diseases and maintained healthy bulbs during the different storage periods.

A field experiment was carried out in sandy soil at El-Ismailia Agricultural Research Station, El-Ismailia Governorate, Agricultural Research Center (ARC) to study the effect of treating the soil with different types of compost (plant residues with organic manure and plant residues with cellulose decomposers), (AM)-mycorrhizae and N2-fixing bacteria on the growth and yield of wheat plants. Plant dry weight recorded a significant increase when the soil was treated with compost provided with cellulose decomposers and biofertilizers. The highest number of tillers obtained with compost B amended with organic manure and biofertilizers.The maximum infection percentage was due to compost A provided with organic manure. The optimum nitrogenase enzyme activity obtained when the soil was treated with compost B plus cellulose decomposers and biofertilization. High significant nitrogen percentage was shown when the soil was amended with compost D + organic manure + biofertilizers. Inoculation with N2-fixers + (AM) mycorrhizae led to the increase of phosphorus % and this was clearly obtained with compost "B" plus cellulose decomposers. Inoculation with mixed diazotrophs + (AM)-mycorrhizae increased potassium % and this was obtained with compost D plus organic manure at the period of 45 days from sowing.Results showed significant increases in yield parameters, i.e., 1000-grain weight, grain yield and straw yield. The addition of compost B amended with organic manure + N2-fixers + (AM) mycorrhizal gave the superior yield. Generally, it was remarkable that the essential role of organic matter represented in compost, N2-fixers and (AM) mycorrhizae in enhancing the growth and yield of wheat.

Newly reclaimed sandy soils are considered one of the main items of agricultural expanding policy in Egypt. Therefore we need to continuous addition of organic matter to increase soil fertility and agricultural production. For this reason, eight heaps were prepared each heap involves four plant residues. One set of four heaps was supplemented with organic manure. Another set was supplemented with cellulose decomposers. Some physical, chemical and microbiological properties were determined during composting process. The important obtained results are as follows: Temperature inside the compost heaps began to rise from the third day of composting and reached maximum values at the third week of the process. From the fourth week there was a gradual decrease in temperature till the end of composting. The pH values of the eight heaps tended slightly to acidic at early intervals of composting process till the 20 th day, then the pH values increased to reach neutral or slightly alkaline by the end of the process. The Gradual increases in EC and bulk density values during the process. The obtained results showed a gradual decrease in organic carbon and organic matter by time and increase in total-N of all composted heaps during the different intervals of composting process. The results showed remarkable decrease in C/N ratio with the progress of the composting process.At the beginning of the composting, total number of mesophilic bacteria was increased, however it was markedly decreased in the third week of composting. Then it was highly increased at the end of composting. The same pattern of the results was also observed with mesophilic fungi and actinomycetes. On the other hand, thermophilic bacteria were sharply increased at the third week and then obviously decreased at the end of the composting process (cooling phase). The same trend was also observed with thermophilic fungi and actinomycetes. It has been also observed that no marked differences were obtained in the total microbial counts of different compost heaps for both mesophilic and thermophilic organisms.In concerning the enzymes activities of common selected fungal, bacterial and actinomycets strains the obtained results were: In regarding to Cellulase enzyme activity, it was obvious that Trichoderma reesei, Bacillus stearothermophilius and Streptomyces antibioticus recorded the highest activity in culture filtrates. In regarding to dehydrogenase enzyme activity, Trichoderma reesei, Bacillus subtilis and Streptomyces roseus exhibited the highest activity. In case of protease activity and also soluble protein the fungus Trichoderma ressei, Bacillus subtilis, and Streptomyces antibioticus showed high protease activity and also high soluble protein content.