Effect of some Metabolic Inhibitors of Oxidative Phosphorylation on Rooting of Cuttings of Phaseolus mungo

2,4-enhances root formation on hypocotyl cuttings made fromdark-grown seedlings of Phaseolus mungo. The effect is increasedby indol-3-ylacetic acid + sucrose. In the presence of indol-3-ylaceticacid + sucrose, root formation is also enhanced by sodium azideand ammonium sulphate, two non-phenolic uncouplers of oxidativephosphorylation. It appears that the enhancement in root formationby these uncoupters is due to increased respiration by removingthe obligatory link to phosphorylation and, thereby, regulatingthe endogenous levels of adenosine triphosphate. This is alsosupported by the fact that root formation in this system isdepressed both by cobalt which counteracts the uncoupling effectof 2,4-dinitrophenol and also by an exogenous supply of adenosinetn phosphate.