(A) Regulation of lateral root (LR) development by GR24 (a synthetic strigolactone), fluridone (inhibitor of SL biosynthesis) and NPA (auxin efflux blocker). (B) Quantitative analyses of the number of lateral roots formed in the above-stated treatments. (C) Effect of GR24 and related pharmacological agents on adventitious rooting in hypocotyl explants derived from 6 d old, dark-grown seedlings. Evaluation of the number of endogenous root initials and their elongation was undertaken in explants cleared after staining with safranin. (D) Quantitative analyses of AR initiation. Each datum indicates mean ± SE from at least 3 replicates, showing changes to be significant at different levels (*P < .05, **P < .01, ***P <.001) from the control, analyzed by one-way ANOVA.