الفهرس 
INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
Objectives:
1- Isolation, purification and identification of strains belonging to Pseudomonas from inside roots of rice plants grown in middle of the Nile delta and N2-fixing cyanobacteria from rice fields of the same area. The obtained two strains along with a rice endophytic Rhizobium leguminosarum biovar trifolii that already tested and found successful for rice biofertilization in the Nile delta will be used as the biofertilizer candidates in this study.
2- Test the performance of those bacteria, individually and when used as consortia, in enhancement of rice seedling growth under gnotobiotic lab culture conditions,
3- Study the possible contribution of them to rice growth and performance when used individually or in consortia inocula preparations in large-scale multilocation rice field experiments in the Nile delta.
Methods& Results:
1- Clover-nodulating Rhizobium from roots of field-grown rice.
2- Isolation and identification of Anabaena spp. and Pseudomonas stutzeri.
3- Growth of rice under gnotobiotic conditions.
4- Screening of plant growth-promotion activities.
5- Field experiments.
Genomic palindromic-PCR fingerprinting and/or PCR-restriction fragment length polymorphism (RFLP) of 16s rDNA identified the cyanobacterium isolate as Anabaena sp. (named as strain ERC102) and also Pseudomonas stutzeri (named as strain ERP-1). Results of the plant growth promotion test for the rhizobial and cyanobacterial strains, that performed under gnotobiotic controlled condition in a growth chambers. Inoculation with the Rlt E11 alone stimulated root and shoot growth of the three rice varieties Sakha 101, Sakha 104 and Giza 178. The plant growth promotion provided by inoculation with Rlt E11 alone was better than for inoculation with the cyanobacterial strain alone or when the two strains mixed in a consortia inoculum.
The obtained results are informative and clearly refer to necessity of adding new biofertilizer candidates to be used for rice biofertilization. This is anticipated to diminish the current excessive use of N-fertilizer in rice production that adversely affects production economy and environmental soundness.
Conclusion:
1-Increase of rice yield over that which can be reached using the full recommended amount of chemical fertilizer-N for the crop, with possible reduction of some 33 - 67% of the chemical fertilizer input;
2. Decrease environmental pollution and health risks originating from the current excessive use of chemical N-fertilizers;
3. Relieve the stress on manufacturing and marketing originating from increasing demand on chemical fertilizers in certain periods of the year. This sometimes makes availability of chemical fertilizers controlled by a sort of “black-market” rather than the legitimate normal market;
4. Decrease energy consumed for production and distribution of chemical fertilizers and direct it to other necessary socioeconomic and industrial uses.