Separation of transit of auxin from uptake: average velocity and reversible inhibition by anaerobic conditions.

An applied pulse of (14)C-indole-3-acetic acid moved down aerobic corn coleoptiles at about 15 millimeters per hour. When sections with a moving pulse were transferred to nitrogen, the rate fell below 2 millimeters per hour. This inhibition was completely reversible; sections returned to air moved the same amount of auxin as untreated aerobic controls.