Glycophytes have a degree
of compartmentation ability, as levels of Na+ up to
1 mmol g−1 DW are quite common in photosynthetically
active leaves of many species. For example, in
a study of two tetraploid wheat genotypes, we concluded
that Na+ became potentially toxic only when
concentrations exceeded 1.25 mmol g−1 DW (equivalent
to about 250 mM Na+ in the leaf tissue water),
as this level correlated with the onset of non-stomatal
reductions in photosynthesis in durum wheat