The sesquiterpene lactone dehydroleucodine reversibly inhibits Allium cepaL. root growth

Here, we prove that dehydroleucodine, a sesquiterpene lactone, at low conce ntrations (25-100 muM) slowed down the Allium cepa L root growth by 22-70% respectively neither affecting cell viability nor cell size. Removal of the drug after 24 h incubation restored the normal growth rate of the roots. H igher concentrations (200 muM) of dehydroleucodine were deleterious for the roots. As cell size did not change, it is most likely that dehydroleucodin e affected some event of cell division cycle making it longer. Thus, dehydr oleucodine could be a useful tool to slow down cell proliferation.