What plant roots know?

Despite their paramount role in plant life, the study of roots has been largely neglected until recently. Here, I shortly describe a few newly-discovered abilities of plants to undergo adaptive changes and execute developmental decisions based on roots' perception of non-resource information pertaining to imminent challenges and opportunities. Seemingly simple in their morphology and architecture and lacking central information-processing centres, roots are able to sense and integrate complex cues and signals over time and space that allow plants to perform elaborate behaviours analogous, some claim even homologous, to those of intelligent animals. Although our knowledge of root behaviour is rapidly expanding, further understanding of its underlying mechanisms is largely preliminary, calling for detailed investigation of the involved cues, signals and information processing controls, as well as their implications for plant development, growth and reproduction under realistic ecological and agricultural settings.