Closing the phenotyping gap: non-invasive electromagnetic induction enables high-throughput screening of crop root function in the field

Time-lapse EMI surveys in an on-farm field experiment predict 3D soil moisture dynamics in sorghum with high accuracy (R2 = 0.83) across 13 genotypes and three row spacings.

• Why it matters: Measuring crop root function at scale in the field is a bottleneck for drought-related crop improvement, limiting exploration of water uptake and root activity in breeding programs.
• What they did: The study integrated electromagnetic induction sensing, inversion modelling, and machine learning using a customised DualEM-21S system to predict depth-specific soil moisture (theta) and derive water use from theta profile changes.
• The result: EMI-derived crop water use is significantly positively correlated with root length density at depths without water stress, and functional root traits vary with growth stage, genotype, row spacing, and interactions.