The worldwide occurrence of soil alkalinisation and salinization has risen due to
prolonged or severe drought periods and inadequate irrigation practices. Alkaline
soil pH and high salinity adversely affect crop productivity by reducing their yield.
Therefore, clarifying the molecular background of salt stress could facilitate the
selection of salt-tolerant plant varieties. Our objective was to assess the tolerance
of Arundo donax to alkaline salt stress caused by irrigation water containing a mixture
of NaHCO3 and Na2CO3 (at a ratio of 1:1) with final concentrations of 80 mM and 200
mM, and pH 10. In terms of physiological parameters the plants were resistant to the
stress treatments. Negative effects on the water balance have been observed only at
the higher salt concentration (200 mM). The K/Na ratio declined correspondingly with
the accumulation of Na. Furthermore, the plants showed increased accumulation of zinc,
while a decrease in the concentration of other elements (such as Ca, Cu, K, Mg, Ni,
S, Si, and Sr) was detected. Antioxidative defence directed by multiple symplastic
enzymes contributed to the high physiological tolerance to the applied stress.
This work was supported by grants from the National Research, Development, and Innovation
Office of Hungary (NKFIH K-132241, GINOP 2.2.1-15 2017-00042) and by the European
Structural and Investment Funds (VEKOP-2.3.3-15-2016-00008).
