Effects of sodium chloride on survival and stem elongation of two Asian pear rootstock seedlings

Survival, leaf burn, and mineral uptake of two Asian Pyrus rootstocks were evaluated under NaCl irrigation. Potted seedlings of 2-year-old pear rootstocks, Pyrus betulifolia Bunge (BET) and P. pyrifolia (Burm f.) Nakai (PYR) were irrigated with 0, 25, 50, 100, 150 or 200 (BET only) mM NaCl solution. BET showed high survival rate and slight leaf injury even under 100 mM NaCl irrigation. PYR however exhibited severe leaf injury and most of the tested plants died under 25 mM NaCl irrigation. Leaf Na concentration in BET subjected to 100 mM was similar to that of PYR at 25 mM. (C) 2000 Elsevier Science B.V. All rights reserved.