© 1986 Heron Publishing—Victoria, Canada
The influence of NaCl on leaf water relations and the proportions of K, Na, Ca, Mg, and Cl in epidermal cells of Fraxinus excelsior L.
S. Leonardi and W. Flückiger
Institute for Applied Plant Biology, Sandgrubenstraße 25, CH-4124 Schönenbuch, Switzerland /
Summary
The influence of NaCl on leaf water relations was investigated in 3–4-year-old, potted Fraxinus excelsior L. trees. Until midsummer, the application of NaCl to the soil resulted in increased leaf water potentials (Ψ) and stomatal
diffusive resistances (rs). The improved water status seems to be due to a latent injury rather than to an adaptive response of the plant because,
despite the initial increases in Ψ and rs, leaf necrosis developed in midsummer. Altered hydraulic resistances were detected at the time the leaves became necrotic.
X-ray analysis of frozen, hydrated leaf tissue from NaCl-treated trees showed substantial increases in Ca2+ and Mg2+ content in the epidermal cells. These changes in elemental composition of the leaves from NaCl-treated plants may be associated
with malfunction of the stomatal apparatus.
