Submit Manuscript

Microbiology Journal

Year: 2011 | Volume: 1 | Issue: 4 | Page No.: 149-158
Facebook Twitter Digg Reddit Linkedin StumbleUpon E-mail

Article Trend

Total views 309

Search

Authors

W.M. Salem

W.F. Sayed

M.S. Ali

Keywords

Research Article

Host-specific Enhancement of Frankia using Aqueous Extracts of Casuarina equisetifolia

W.M. Salem, W.F. Sayed and M.S. Ali
The research study was conducted to study the impact of aqueous extracts of different C. equisetifolia parts (green cladodes, dry cladodes, roots and seeds) on growth of four Frankia strains, rhizospheric isolates and C. equisetifolia seed germination. The concentrations of some macronutrients (Na, K, Ca, Mg and P) and micronutrients (Mn, Fe, Cu and Zn) were determined in the aqueous extracts. In vitro growth of all the tested Frankia strains was stimulated by the aqueous root extracts. Growth of Azotobacter sp., Bacillus subtilis, Aspergillus niger and A. versicolor was either inhibited or not affected by different extract concentrations. On the other hand, seed and dry cladode extracts increased C. equisetifolia seed germination rate up to 136 and 132%, respectively. The more-pronounced Frankia growth stimulation, caused by Casuarina root extract, compared to the dominant rhizospheric isolates suggested that compounds released from root host tissue such as the high concentration of metal ions Ca2+, Mg2+ and P and low concentration of heavy metalions Mn2+ specifically favor all Frankia strains tested. The released compounds may be a stimulating factor in the presence of Frankia in soils near a Casuarina roots and this was suggested a host-specific enhancement of the endosymbiont Frankia.
PDF Fulltext XML References Citation

Leave a Comment

Your email address will not be published. Required fields are marked *