Arabidopsis parp mutants are hypersensitive to DNA damage agents.

Wild-type Col-0 and parp mutant seeds were grown on MS agar medium supplemented with the genotoxic agents bleomycin (A) or mitomycin C (B). Sensitivity to DNA damage agents was scored as the percentage of plants that had not yet developed true leaves after 14 d. Mean and standard error of the mean are shown for one experiment; experiment was performed three times with similar results. Genotypes not sharing same letter on graph are significantly different at the high concentration (ANOVA Tukey HSD P < 0.05 across three experiments).