Differing responses of NR activity to drought were observed inleaves and roots (Fig. 6). NR activity increased in roots (Fig. 6Band D) in all the water stress treatments when compared to con-trol conditions – the highest values (P < 0.05) being for ungraftedplants, 5/cultivar, and 8/cultivar plants at 7% PEG and T2 (Fig. 6D).