الفهرس 
Introduction
BiofertilizersOnly 14 pages are availabe for public view
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Abstract
Healthy plants carry populations of endophytic bacteria. Endophytes with growth-promoting properties are desirable for improvement of agricultural crop yield. A favorable plant-endophyte association would minimize the usage of agricultural chemicals, such as chemofertilizers and pesticides saving costs and reducing pollutants to environment. This project mainly aimed to find potentiality of endophytes as biofertilizers in corn (Zea mays L.) to improve productivity. The occurrence of endophytic bacteria was studied in two crop plants belonging to Poaceae; Phragmites and wheat. from the two groups of studied plants, 21 bacterial isolates were isolated, purified and coded according to the host plant. These purified isolates assessed by maize seed bacterization in laboratory. Three of the 21 screened purified isolates selected for further studies as they gave the best results in improving maize grains germination. Cultural, morphological properties and molecular identification of the three bacterial isolates were carried out via 16S rRNA gene sequencing. Two of these bacterial isolates E1S2 and MK2R2 were Gram negative belonging to genus Enterobacter and Klebsiella while the last B2L2 was Gram positive and belonging to genus Bacillus. Wheat isolates MK2R2 and B2L2 were identified as Klebsiella michiganensis W14 and Bacillus subtilis NRRL B-23049 respectively while Phragmites isolate E1S2 was identified as Enterobacter cloace subsp. Dissolvens ATCC 2337. Laboratory priming of the three identified isolates (Enterobacter subsp. Dissolvens ATCC 2337 E1S2, Klebsiella michiganensis W14 MK2R2 and Bacillus subtilis NRRL B-23049 B2L2) individually and in consortia (co-culturing) to evaluate plant growth promotion potentiality of endophytic bacterial isolates on maize were studied. Treatments; T3 representing the single culture (B2L2), T5, T6 and T8 representing the co-cultivated cultures (MK2R2, B2L2 and E1S2), (B2L2 and E1S2) and (MK2R2 and B2L2) respectively, increased growth parameters compared with controls and then applied in field experiment either alone or in combination with urea. from field experiment, Klebsiella michiganensis W14 MK2R2 and Bacillus subtilis NRRL B-23049 B2L2 either alone (treatment 8) or in combination with Enterobacter cloace subsp. Dissolvens ATCC 2337 E1S2 (treatment 5 (in presence of fertilizer (T8+F and T5+F) surpassed significantly the treatment lacked the fertilizer as well as fertilizer treated plants and control plants in all agronomic parameters either in vegetative or fruiting stages. So it could be summarized that, the endophytic bacterial treatments in combination with the recommended dose of urea fertilizer (T8+F and T5+F) were the best in increasing maize yield. In organic agriculture, where the use of harmful chemicals has to be avoided, the seed bacterization with endophytic bacteria could be recommended as a cheap and potent biofertilizer for improving maize yield.