“…In spite of improved pH conditions, the elevated concentration of soluble Na in the gypsum-amended soils could be toxic to the plants and therefore become a constraint to the growth of plants (Luan et al, 2009). This explains the observed poor growth performance for all the test plant species except for Digit grass, which was well adapted to the soluble Na-rich conditions (Brauer and Wolfson, 1986). The Na concentration in the shoots was much lower in the Digit grass than other grass species (Fig.…”