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NASA NTRS · 20040088446

Root elongation against a constant force: experiment with a computerized feedback-controlled device

Kuzeja, P. S.·Lintilhac, P. M.·Wei, C.
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Abstract

Axial force was applied to the root tip of corn (Zea mays L. cv. Merit) seedlings using a computerized, feedback-controlled mechanical device. The system's feedback capability allowed continuous control of a constant tip load, and the attached displacement transducer provided the time course of root elongation. Loads up to 7.5 g decreased the root elongation rate by 0.13 mm h-1 g-1, but loads 7.5 to 17.5 g decreased the growth rate by only 0.04 mm h-1 g-1. Loads higher than 18 g stopped root elongation completely. Measurement of the cross-sectional areas of the root tips indicated that the 18 g load had applied about 0.98 MPa of axial pressure to the root, thereby exceeding the root's ability to respond with increased turgor pressure. Recorded time-lapse images of loaded roots showed that radial thickening (swelling) occurred behind the root cap, whose cross-sectional area increased with tip load.

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Non-NASA CenterNASA Discipline Plant BiologyZea mays/cytology/growth & development/physiologyPlant Roots/cytology/growth & development/physiologyPlant Root Cap/cytology/growth & development/physiologyGravitationComparative StudyImage Processing, Computer-AssistedTime FactorsPhysical StimulationBiophysics

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Kuzeja, P. S., Lintilhac, P. M., Wei, C.. 2001-05-01. Root elongation against a constant force: experiment with a computerized feedback-controlled device. https://ntrs.nasa.gov/citations/20040088446

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