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Maize root growth responses to penetration of a bilayered soil

Studying the influence of soil strength on root growth dynamics, Popova et al. document the mechanical and tropic responses of primary roots of maize (Zea mays) seedlings further to penetration of a bilayered soil consisting of loose loamy sand on top and a coarser, denser layer beneath.

Typical MRI projection images of maize roots growing in mixed sands with different bulk densities and structures.
Typical MRI projection images of maize roots growing in mixed sands with different bulk densities and structures. Full details in Popova et al.(2016).

Upon reaching the compacted soil in the lower layer, the elongation rate of the primary roots nearly halved and the tortuosity and deflection of the root path significantly changed in response to contact with the changing soil texture. The resulting ‘waviness’ of the root serves as a key indicator of the maize roots’ response to touch stimuli as they encounter a changing physical soil environment.

Root Biology Issue This paper is part of the Root Biology Special Issue.

Written by Annals of Botany Office

The Annals of Botany Office is based at the University of Oxford.

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