Cowpea plants were initially exposed to an osmotic shock
induced by 200 m NaCl, followed or not by recovery after 3 d treatment. The salt treatment rapidly caused a cessation of
leaf growth, as indicated by the RGR which reached values
near to zero after only 1 d treatment (Fig. 1a), paralleled by
the transpiration rate (Fig. 1b). Also, leaf RWC decreased
significantly after 1 d treatment (Fig. 1c), associated with
mild leaf wilting. In contrast, the leaf dry mass production of
plants irrigated with an NaCl-free nutrient solution (control)
increased linearly as indicated by the almost constant RGR
over the experimental period (Fig. 1a).