Conditions for the emergence of circumnutations in plant roots

The plant root system shows remarkably complex behaviors driven by environmental cues and internal dynamics, whose interplay remains largely unknown. A notable example is circumnutation growth movements, which are growth oscillations from side to side of the root apex. Here we describe a model capable of replicating root growth behaviors, which we used to analyze the role of circumnuntations, revealing their emergence I) under gravitropic stress, as a combination of signal propagation and sensitivity to the signal carriers; II) as a result of the interplay between gravitropic and thigmotropic responses; and III) as a behavioral strategy to detect and react to resource gradients. The latter function requires the presence of a hypothetical internal oscillator whose parameters are regulated by the perception of environmental resources.

Automated summary

The study describes a model capable of replicating root growth behaviors and analyzes the role of circumnutation movements in response to environmental cues. The research reveals that circumnutations emerge under gravitropic stress and are a behavioral strategy for roots to detect and react to resource gradients, with an internal oscillator regulating their parameters based on environmental resource perception.