AL-PCD rates in the DAD1 over-expressing line of Arabidopsis thaliana. Five day old seedlings of DAD1 over-expressing (OE) and wild-type (WT) lines of Arabidopsis thaliana were subjected to a heat treatment at 45°C for 10 min or no heat treatment. Root hairs were scored 24 hr later and root hairs showing retraction and condensation of the cytoplasm and no FDA staining were deemed to have undergone AL-PCD. Root hairs showing neither FDA staining nor retraction of the cytoplasm, were scored as necrotic. Rates of AL-PCD or Total Cell Death (TCD) (TCD = necrotic + AL-PCD) were plotted. Error bars = standard error of n = 3 replicates.