Root elongation growth and lunisolar tidal acceleration

Correlative evidence suggests a relationship between the lunisolar tidal acceleration and the elongation rate of Arabidopsis thaliana roots grown under conditions of constant low light. Barlow et al. use high temporal- and spatial-resolution video imaging to study root elongation in conjunction with geophysical variables for seedlings grown in a constant environment. They find that elongation responds not only to variation of the lunisolar force but also seems to adjust to variations in the geomagnetic field, as evaluated from the disturbance storm time and ap indices. They conclude that both lunisolar tidal acceleration and the geomagnetic field should be considered as modulators of root growth rate alongside other, stronger and more well-known abiotic environmental regulators.