Arbuscular Mycorrhizal Fungi and Spermine Alleviate the Adverse Effects of Salinity Stress on Electrolyte Leakage and Productivity of Wheat Plants

IBRAHIM A. H., ABDEL-FATTAH G. M., EMAM F. M., ABD EL-AZIZ M. H. & SHOKR A. E. 2011. Arbuscular mycorrhizal fungi and spermine alleviate the adverse effects of salinity stress on electrolyte leakage and productivity of wheat plants. - Phyton (Horn, Austria) 51(2): 261-276, with 3 figures. A pot experiment was conducted to investigate the possible role of arbuscular mycorrhizal (AM) fungi, spermine and their combination in alleviating the adverse effects of salinity stress on electrolyte leakage (EL), root colonization and productivity of wheat plants. Two levels of salinized underground water were used (6.09 dSm(-1) and 10.63 dSm(-1)). At three studied growth stages, salinity stress markedly increased the electrolyte leakage of wheat leaves and the effect was increased with increasing the salinity level. Although the application of low salinity level did not decrease shoot dry weight and grains number of wheat plants, it significantly decreased grain yield and harvest index of these plants. The highest salinity level markedly reduced all yield parameters. The imposed salinity stress significantly decreased total carbohydrates, protein and moisture level of the developed wheat grains. Conversely, the level of ash and fibers was increased in response to the applied stress. The inoculation with arbuscular mycorrhizal fungi mitigated the detrimental effects of salinity on EL, yield parameters and grains quality of wheat plants when compared to non-mycorrhizal treatments. The highest root colonization with AM fungi was observed at the booting stage, whereas the lowest one was reported at the tillering phase. Exogenous application of spermine reduced EL and improved the productivity of wheat plants grown in the stress conditions. Interestingly, the dual treatment with AM fungi and spermine added more enhancement of wheat yield in both control and salt stress conditions via reduction of EL and increase of mycorrhizal colonization.