RECOVERY OF NITRATE REDUCTASE-ACTIVITY IN WHEAT LEAVES AFTER A PERIOD OF SEVERE WATER-STRESS

In-vivo leaf Nitrates Reductase Activity (NRA) and water potential ( psi(W) ) of wheat, were measured in water stressed plants, grown in greenhouse and during recovery after resumption of watering. Although during the stress period psi(W) values were as low as -1.6 to -2.7 MPa, NRA activity was completely restablished 24 hours after rewatering, whenever psi(W) values had also recovered and were similar to controls. These results demonstrate the great capacity of NRA to recover from severe water stress situations.