Nitrogen (N), Phosphorus (P) and Potassium (K) are the major essential macro-nutrients for plants. The ability of soil bacteria to provide available forms of these nutrients to plants is an important feature in the bacterial strain used as a bio-fertilizer. In this study, fifteen isolates of Azotobacter spp were isolated. The efficiency levels of the N2-fixation were tested, the isolates reduced acetylene at rates of 6.348 - 1381.023 nmoles C2H4/ml/day. The most active isolate was No. AZ 8 that identified as Azotobacter chroococcum MF135558. Twenty-one phosphate-solubilizing bacteria (PSB) were isolated and solubilization efficiency % (SE%) of each isolate was determined by spot inoculation technique. Five isolates (PSB 3, PSB 7, PSB 8, PSB 12 and PSB 14) were chosen due to their high solubilization efficiency % (SE%) 182.35, 173.33, 222.22, 170.00 and 194.11 %, respectively. The five P-solubilizing bacteria were tested for their ability to solubilize P from tri-calcium phosphate and rock phosphate in liquid Pikovskaya’s medium. The highest quantity of released phosphorus in actively growing culture was 36.52 mg/100 ml after 28 days of incubation and 1.095 mg/100 ml after 3 days of incubation on tri-calcium phosphate and rock phosphate, respectively by isolate PSB 14 which was identified as Klebsiella oxytoca MF135559. Five isolates of K-releasing bacteria (KRB) were isolated on Alexandroov’s medium and were tested to release K from mica-muscovite. All the tested isolates can release potassium from mica but not in equal efficiency. The most efficient isolate namely KRB-2 could release 7.05 ppm after 6 weeks of incubation. It was identified as Rhizobiumpusense MF135560.
Hauka, F., Afify, A., & El-Sawah, A. (2017). Efficiency Evaluation of some Rhizobacteria Isolated from Egyptian Soils, In vitro as Biofertilizers.. Journal of Agricultural Chemistry and Biotechnology, 8(9), 231-235. doi: 10.21608/jacb.2017.38779
MLA
F. Hauka; Aida Afify; A. El-Sawah. "Efficiency Evaluation of some Rhizobacteria Isolated from Egyptian Soils, In vitro as Biofertilizers.", Journal of Agricultural Chemistry and Biotechnology, 8, 9, 2017, 231-235. doi: 10.21608/jacb.2017.38779
HARVARD
Hauka, F., Afify, A., El-Sawah, A. (2017). 'Efficiency Evaluation of some Rhizobacteria Isolated from Egyptian Soils, In vitro as Biofertilizers.', Journal of Agricultural Chemistry and Biotechnology, 8(9), pp. 231-235. doi: 10.21608/jacb.2017.38779
VANCOUVER
Hauka, F., Afify, A., El-Sawah, A. Efficiency Evaluation of some Rhizobacteria Isolated from Egyptian Soils, In vitro as Biofertilizers.. Journal of Agricultural Chemistry and Biotechnology, 2017; 8(9): 231-235. doi: 10.21608/jacb.2017.38779
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