with Hoagland solution
basal mixture no. 2 at pH 5.5. The environmental conditions
inside the chamber were the following: photoperiod 14 h, PAR
500 mE m2 s1, day/night T 20/20 C, RH 65%. After 8 weeks of
acclimation, 2 mM of Zn (as ZnCl2) were added to the solution of
one hydroponic system once aweek, for 3 consecutiveweeks, while
the other hydroponic system was kept as control. Measurements
were made after 6 days from the last dose of Zn, on 1e2 fully
expanded leaves from the top of each plant, (N ¼ 10 for both treated
and control plants, Table 1).