Effect of several stresses on transcript levels of Hsp70 and sHsp. Two-week-old Arabidopsis plants (control, 120 µmol quanta m−2 s−1, 16 h light period at 25°C) were exposed to wilting (2 h), heat shock (45°C, 2 h), UV-light (15 and 30 min) and different light intensities (120, 550 and 950 µmol quanta m−2 s−1 for 2 h). Transcript levels of Hsp70 and sHsp were detected using RNA gel-blot analysis. Each lane was loaded with 20 µg total RNA. Equal loading was verified by rRNA visualization after ethidium bromide staining.