Advertisement

Plant and Soil

, Volume 255, Issue 1, pp 351–359 | Cite as

Non-invasive imaging of roots with high resolution X-ray micro-tomography

  • P.J. GregoryEmail author
  • D. J. Hutchison
  • D. B. Read
  • P. M. Jenneson
  • W. B. Gilboy
  • E. J. Morton
Article

Abstract

X-ray micro-tomography is a well-established technique for non-invasive imaging and evaluation of heterogeneous materials. An inexpensive X-ray micro-tomography system has been designed and built for the specific purposes of examining root growth and root/soil interactions. The system uses a silver target X-ray source with a focal spot diameter of 80 μm, an X-ray image intensifier with a sampling aperture of about 100 μm, and a sample with a diameter of 25 mm. Pre-germinated wheat and rape seeds were grown for up to 8–10 days in plastic containers in a sandy loam soil sieved to < 250 μm, and imaged with the X-ray system at regular intervals. The quality of 3 D image obtained was good allowing the development and growth of both root axes and some first-order laterals to be observed. The satisfactory discrimination between soil and roots enabled measurements of root diameter (wheat values were 0.48–1.22 mm) in individual tomographic slices and, by tracking from slice to slice, root lengths were also measured. The measurements obtained were generally within 10% of those obtained from destructive samples measured manually and with a flat-bed scanner. Further developments of the system will allow more detailed examination of the root:soil interface.

imaging root length tomography wheat X-ray imaging 

Preview

Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

References

  1. Adderley W P, Simpson I A and MacLeod G W 2001 Testing highresolution X-ray computed tomography for the micromorphological analyses of archaeological soils and sediments. Archaeol. Prospect. 8, 107-112.Google Scholar
  2. Asseng S, Aylmore L A G, MacFall J S, Hopmans J W and Gregory P J 2000 Computer-assisted tomography and magnetic resonance imaging. In Techniques for Studying Roots. Eds. A L Smit, A G Bengough, C Engels, M van Noordwijk, S Pellerin and S C van de Geijn. pp. 343-363. Springer, Berlin.Google Scholar
  3. Aylmore L A G 1993 Use of computer-assisted tomography in studying water movement around plant roots. Adv. Agron. 49, 1-54.Google Scholar
  4. Barrett H H and Swindell W 1981 Radiological Imaging: The Theory of Image Formation, Detection and Processing. pp 348-349. Academic Press, London.Google Scholar
  5. Bragg P L, Govi G and Cannell R Q 1983 A comparison of methods, including angled and vertical minirhizotrons, for studying root growth and distribution in a spring oat crop. Plant Soil 73, 435-440.Google Scholar
  6. Brown J M, Johnson G A and Kramer P J 1986 In vitro magnetic resonance microscopy of changing water content in Pelargonium hortorum roots. Plant Physiol. 82, 1158-1160.Google Scholar
  7. Gregory P J 1979 A periscope method for observing root growth and distribution in field soil. J. Exp. Bot. 30, 205-214.Google Scholar
  8. Hainsworth J M and Aylmore L A G 1983 The use of computerassisted tomography to determine spatial distribution of soil water content. Aust. J. Soil Res. 21, 435-443.Google Scholar
  9. Hamza M A and Aylmore L A G 1992 Soil solute concentration and water uptake by single lupin and radish plant roots. I. Water extraction and solute accumulation. Plant Soil 145, 187-196.Google Scholar
  10. Hamza M A, Anderson S H and Aylmore L A G 2001 Studies of soil water drawdowns by single radish roots at decreasing soil water content using computer-assisted tomography. Aust. J. Soil Res. 39, 1387-1396.Google Scholar
  11. Heeraman D A and Juma N G 1993. A comparison of minirhizotron, core and monolith methods for quantifying barley (Hordeum vulgare L.) and fababean (Vicia faba L.) root distribution. Plant Soil 148, 29-41.Google Scholar
  12. Heeraman D A, Hopmans J W and Clausnitzer V 1997 Three dimensional imaging of plant roots in situ with X-ray computed tomography. Plant Soil 189, 167-179.Google Scholar
  13. Hopmans J W, Vogel T and Koblik P D 1992 X-ray tomography of soil water distribution in one-step outflow experiments. Soil Sci. Soc. Am. J. 56, 355-362.Google Scholar
  14. Hounsfield G N 1972 A method of and apparatus for examination of a body by radiation such as X-or gamma radiation. British Pat. No. 1283915, London, UK.Google Scholar
  15. Jarvis R A 1968 Soils of the Reading District. Memoir of the Soil Survey of Great Britain England and Wales. Harpenden, Herts, UK.Google Scholar
  16. Jenneson P M, Morton E J and Gilboy W B 2002 An X-ray microtomography system optimised for the low-dose study of living organisms. Applied Rad. Isotopes (in press).Google Scholar
  17. Ketcham R A and Carlson W D 2001 Acquisition, optimization and interpretation of X-ray computed tomographic imagery: applications to the geosciences. Comp. Geosci. 27, 381-400.Google Scholar
  18. Kirchoff G and Pendar CE 1995 Delta-T Scanner-User Manual v2.0. Ed. N Webb. Delta-T Devices Ltd., Cambridge, U.K.Google Scholar
  19. Livesley S J, Stacey C L, Gregory P J and Buresh R J 1999.Sieve size effects on root length and biomass measurements of maize (Zea mays) and Grevillea robusta. Plant Soil 207, 183-193.Google Scholar
  20. MacFall J S and Johnson G A 1994 Use of magnetic resonance imaging in the study of plants and soils. In Tomography of Soil-Water-Root Processes. Eds. S H Anderson and J W Hopmans. pp. 99-113. SSSA Special Publication no. 36. SSSA, Madison.Google Scholar
  21. Macedo A, Crestana S and Vaz C M P 1998 X-ray microtomography to investigate thin layers of soil clod. Soil Till. Res. 49, 249-253.Google Scholar
  22. Pierret A, Capowiez Y, Moran C J and Kretzschmar A 1999 X-ray computed tomography to quantify tree rooting spatial distributions. Geoderma 90, 307-326.Google Scholar
  23. Smit A L, George E and Groenwold J 2000 Root observations and measurements at (transparent) interfaces with soil. In Techniques for Studying Roots. Eds. A L Smit, A G Bengough, C Engels, M van Noordwijk, S Pellerin and S C van de Geijn. pp. 236-271. Springer, Berlin.Google Scholar
  24. Taylor H M 1987 Minirhizotron Observation Tubes: Methods and Applications for Measuring Rhizosphere Dynamics. ASA Special Publ. 50. ASA, CSSA and SSA, Madison, WI.Google Scholar
  25. Young I M, Crawford J W and Rappoldt C 2001 New methods and models for characterising structural heterogeneity of soil. Soil Till. Res. 61, 33-45.Google Scholar

Copyright information

© Kluwer Academic Publishers 2003

Authors and Affiliations

  • P.J. Gregory
    • 1
    Email author
  • D. J. Hutchison
    • 1
  • D. B. Read
    • 1
  • P. M. Jenneson
    • 2
  • W. B. Gilboy
    • 2
  • E. J. Morton
    • 2
  1. 1.Department of Soil ScienceThe University of Reading, WhiteknightsReadingU.K.
  2. 2.Department of PhysicsUniversity of SurreyGuildfordU.K

Personalised recommendations