Circumnutation and gravitropism cause root waving in<i>Arabidopsis thaliana</i>

Abstract

Arabidopsis thaliana roots grow in a wavy pattern on inclined agar plates. This waving behaviour has been interpreted as representing a gravitropism-dependent thigmotropic response. We argue instead that this root waving represents primarily a flattened spiral growth pattern resulting from circumnutation and gravitropism.