Salt Tolerance and Chemical Composition of Rhodes and Dallis Grasses Grown in Sand Culture

Abstract

Dallis and Rhodes grasses were grown in sand cultures subjected to 7 series of treatments. In addition to the base nutrient (control) solution, 6 salts were added singly to the base nutrient soln.[long dash]NaHCO3,MgC12, NaCl, Na2SO4, NaNO3 and CaCl2. Dallis grass is much less salt tolerant than Rhodes grass. Although the NaHCO3 treatment was without effect on the growth of Rhodes grass, it was exceedingly toxic to Dallis grass. Rhodes grass accumulated Na readily in the tops, whereas the Na content of Dallis was characteristically low. The different treatments brought about marked variations in mineral composition of both grasses, and with the exception that poor growth of the MgCl2 cultures was directly related to excessive accumulations of Mg, the observed growth responses could not be conclusively associated with the status of accumulated inorganic ions. Excepting the MgCl2 and NaHC03 treatments which induced specific toxic symptoms, growth response to the salinized culture solns. was most logically interpreted in terms of physiol. availability of water.