While Na + is not an essential nutrient for all plants, it is essential for halophytes , whichaccumulate salt in vacuoles to maintain turgor and growth. A few of the C 4 plants (except corn and sorghum) need Na + essentially for specifi c functions,such as in the concentration of CO 2(Subbarao et al. 2003 ). Na + can be benefi cial to plants under conditions of K + defi ciency (Maathuis 2014 ). Na + can undertake osmotic functions, reduce the total K + requirements and improve growth when the lack of K + is a limiting factor. A near-complete replacement of K + by Na + in its osmotic function is possible ( Shabala and Mackay 2011 ; Gattward et al. 2012 ). High- affi ity Na +uptake probably occurs in most of the land plants (Haro et al. 2010 ). Benefi cial effects of sodium especially at a low concentration (