Improving salinity tolerance of Acacia saligna (Labill.) plant by arbuscular mycorrhizal fungi and Rhizobium inoculation

Abstract

This study was carried out to investigate the alleviation of salt stress (0, 6.25, 12.50 and 25 dS/m) on growth and development of Acacia saligna, grown in sandy loam sterile soil by using arbuscular mycorrhizal fungi (AMF) and Sinorhizobium terangae (R), individually or in combination (AMF+R). Growth and nodulation parameters, leaf osmotic adjustment and chemical analysis were used as parameters. Salt stress increases the percentage of sodium (Na) and calcium (Ca) contents as well as proline; meanwhile, it reduces the leaf osmotic potential, growth parameters, nodulation parameters, Nitrogen, phosphorus, potassium (N. P. K.) contents, total carbohydrates percentages and chlorophyll contents. Co-inoculated (AMF+R) stressed plants were able to maintain a higher osmotic potential of cells leading to the significantly rapid growth, enhanced nodulation parameters, N, P, K, Ca, total carbohydrates percentages and chlorophyll contents as well as proline in leaves, and significantly reduced the Na percentage. In conclusion, Co-inoculated (AMF+R) enabled the plants to maintain osmotic adjustments and enhanced the plants tolerance against salinity.

Key words: Acacia saligna, salinity, Arbascular mycorrhizal fungi and Rhizobium.