Munns (1993) proposed
a two-stage model to describe plant response to salinity: growth is
first reduced by a decrease in soil water potential (a water stress
effect), and later by the effect of salt injury on the older leaves,
which die owing to an increase of salt in the cell components.
Munns (1993) also proposed that the accelerated death of older
leaves led to a decrease in the supply of carbohydrates or growth
hormones to meristematic regions, thereby inhibiting growth.