Effects of a hydrophilic polymer soil amendment on stress tolerance of Eucalyptus saligna

This study evaluated the effect of the hydrophilic polymer Super-AB-A-300 on salt and drought resistance in Eucalyptus saligna Sm. One-year-old cuttings of E. saligna were treated with salt (2 L of 300 mM NaCl), drought stress, and salt plus drought stress; an untreated set of cuttings was used as a control. All treatments were conducted with and without the Super-AB-A-300 polymer in the soil mixture. The Super-AB-A-300 polymer held more water in the soil during water-deficit conditions and promoted tolerance to salinity and drought stresses in the E. saligna rooted cuttings. In addition, the Super-AB-A-300 polymer retained Cl- and Na+ in the soil solution due to its high water-holding capability and the exchangeable K+ in the Super-AB-A-300 resulted in an amended K+ /Na+ balance in the salt-treated plants. Furthermore, the Super-AB-A-300 polymer promoted greater resistance to salinity plus drought stresses, due to the salt- and water-holding capabilities of the polymer.