Figure 6.

Constitutive heat shock tolerance in railway plants. The percentage of seedlings exhibiting partial or total bleaching of their cotyledons and leaves after heat shock treatment is shown. H indicates healthy after treatment (green), and B indicates bleached after treatment (orange). Acclimated seedlings were subjected to a 3-h 37°C pretreatment 2 d prior to a 1-h heat shock at 45°C, while nonacclimated seedlings were incubated directly for 1 h at 45°C. Bleaching was often nonlethal even for KA plants.