Auxin—controlled root growth and ethylene production

Abstract Growth and ethylene production by lentil root tips treated with varying concentrations of indolylacetic and indolylacrylic acids were measured. Stimulation of growth by low concentrations of auxin was accompanied by a reduced ethylene production; growth inhibition by high levels of auxin induced a diminished ethylene evolution. Application of a rhizobitoxine analogue increased growth and reduced ethylene evolution. Simultaneous application of auxin and rhizobitoxine analog reduced ethylene evolution even though growth was inhibited. This indicated the non-dependency of auxin-controlled root growth upon ethylene production.