Twelve-d-old rice seedlings with 3 leaves were exposed to 30 ◦C
(non-HS) and 45 ◦C (HS) for 3 h in the dark, then grown in halfstrength
Kimura B solution with or without 5 M CdCl2 at 30/25 ◦C
day/light. Cd toxicity was first shown in the second leaves of rice
seedlings, so the second leaves were used for all chemical measurements
and enzyme assays.