Plant and Soil

, Volume 272, Issue 1–2, pp 327–336 | Cite as

Ability of seedling roots of Lolium perenne L. to penetrate soil from artificial biopores is modified by soil bulk density, biopore angle and biopore relief



To predict root growth in heterogeneous soil, we need to understand when roots will grow into, along and out from continuous biopores. In this study we determined the effect of biopore angle and wall roughness on root penetration into surrounding soil of different bulk densities. Straight ‘artificial biopores’, 3-mm diameter and 34-mm long, were formed without radial compression in soil compacted to bulk densities of 1.25, 1.38 or 1.50 Mg m−3. Biopores were inclined at 40° or 90° from the horizontal and their walls scarified or left smooth. Seminal roots of ryegrass (Lolium perenne) were grown for 7 days in the biopores and their penetration of the surrounding soil examined. Few roots (13%) penetrated soil from vertical biopores while most roots (78%) in 40°-from-horizontal biopores grew for only short distances (4–24 mm) before penetrating soil. As soil bulk density increased, the length of roots remaining in 40°-from-horizontal biopores increased, although scarification modified this effect by decreasing the distances roots grew before penetrating soil. Compared with smooth artificial biopores, micrographs of soil surfaces excavated by earthworms (Aporrectodea rosea) showed they were relatively uneven. This study provides a basis for developing simulation models of root growth in heterogeneous soil containing biopores.


biopore angle earthworm burrow perennial ryegrass root elongation seedling roots soil bulk density surface relief 


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  1. Bengough, A G 1991The penetrometer in relation to mechanical resistance to root growthSmith, K AMullins, C E eds. Soil Analysis: Physical MethodsMarcel DekkerNew York431445Google Scholar
  2. Cockroft, B, Barley, K P, Greacen, E L 1969The penetration of clays by fine probes and root tipsAust. J. Soil Res.7333348Google Scholar
  3. Dexter, A R 1978Tunnelling in soil by earthwormsSoil Biol. Biochem.10447449Google Scholar
  4. Dexter, A R 1986Model experiments on the behaviour of roots at the interface between a tilled seed-bed and a compacted sub-soil. I. Effects of seed-bed aggregate size and sub-soil strength on wheat rootsPlant Soil95123133Google Scholar
  5. Dexter, A R 1987Mechanics of root growthPlant Soil98303312Google Scholar
  6. Dexter, A R, Hewitt, J S 1978The deflection of plant rootsJ. Agric. Eng. Res.231722Google Scholar
  7. Edwards, C A, Lofty, J R 1980Effect of earthworm inoculation upon the root growth of direct drilled cerealsJ. Appl. Ecol.17533543Google Scholar
  8. Ehlers, W, Köpke, U, Hesse, F, Böhm, W 1983Penetration resistance and root growth of oats in tilled and untilled loess soilSoil Tillage Res.3261275Google Scholar
  9. Evans, P S 1970Root growth of Lolium perenne L. 1. Effect of plant age, seed weight, and nutrient concentration on root weight, length and number of apicesN. Z. J. Bot.8344356Google Scholar
  10. Evans, P S 1977Comparative root morphology of some pasture grasses and cloversN. Z. J. Agric. Res.20331335Google Scholar
  11. FAO–UNESCO 1974 Soil Map of the World. Legend. Vol. 1. UNESCO, Paris.Google Scholar
  12. Genstat 5 Committee 1987 Genstat 5 Reference Manual. Clarendon Press, Oxford. 749 pp.Google Scholar
  13. Glinski, J, Lipiec, J 1990Soil Physical Conditions and Plant RootsCRC PressBoca Raton, USA250Google Scholar
  14. Gooderham, P T 1977Some aspects of soil compaction, root growth and crop yieldAgric. Prog.523344Google Scholar
  15. Holmes, L C, Leeper, G W, Nicolls, K D 1940Soil and land utilization survey of the country around BerwickProc. Roy. Soc. Victoria52177238Google Scholar
  16. Lee, K E 1985EarthwormsTheir Ecology and Relationship with Soil and Land Use. Academic PressSydney411Google Scholar
  17. Logsdon, S D, Linden, D R 1992Interactions of earthworms with soil physical conditions influencing plant growthSoil Sci.154330337Google Scholar
  18. Materechera, S A, Dexter, A R, Alston, A M 1991Penetration of very strong soils by seedling roots of different plant speciesPlant Soil1353134Google Scholar
  19. Materechera, S A, Alston, A M, Kirby, J M, Dexter, A R 1992Influence of root diameter on the penetration of seminal roots into a compacted subsoilPlant Soil144297303Google Scholar
  20. McKenzie, B M 1988Earthworms and their Tunnels in Relation to Soil Physical PropertiesUniversity of AdelaideSouth AustraliaPh.D. ThesisGoogle Scholar
  21. McKenzie, B M, Dexter, A R 1993Size and orientation of burrows made by the earthworms Aporrectodea rosea and A. caliginosaGeoderma56233241Google Scholar
  22. Passioura, J B 1985Roots and water economy of wheatDay, WAtkin, R K eds. Wheat Growth and ModellingPlenum PressNew York185199Google Scholar
  23. Passioura, J B 1991Soil structure and plant growthAust. J. Soil Res.29717728Google Scholar
  24. Passioura, J B, Stirzaker, R J,  et al. 1993Feedforward responses of plants to physically inhospitable soilBuxton, D R eds. International Crop Science I.. International Crop Science Congress, Ames, Iowa. 14–22 July 1992Crop Science Society of AmericaMadison715719Google Scholar
  25. Reid, J B 1981Observations on root hair production by lucerne, maize and perennial grass grown in a sandy loamPlant Soil62319322Google Scholar
  26. Shierlaw, J, Alston, A M 1984Effect of soil compaction on␣root growth and uptake of phosphorusPlant Soil771528Google Scholar
  27. Stirzaker, R J, Passioura, J B, Wilms, Y 1996Soil structure and plant growth: impact of bulk density and bioporesPlant Soil185151162Google Scholar
  28. Wang, J, Hesketh, J D, Woolley, J T 1986Preexisting channels and soybean rooting patternsSoil Sci.141432437Google Scholar
  29. Whiteley, G M, Dexter, A R 1981Elastic response of the roots of field cropsPhysiol. Plant.51407417Google Scholar
  30. Whiteley, G M, Dexter, A R 1983Behaviour of roots in cracks between soil pedsPlant Soil74153162Google Scholar
  31. Whiteley, G M, Hewitt, J S, Dexter, A R 1982The buckling of plant rootsPhysiol. Plant.54333342Google Scholar
  32. Wood, F H 1973Life cycle and host–parasite relationships of Aglenchus costatus (de Man, 1921) Meyl, 1961 (Nematoda: Tylenchidae)N. Z. J. Agric. Sci.16373380Google Scholar
  33. Young, I M 1998Biophysical interactions at the root–soil interface: A reviewJ. Agric. Sci., Camb.13017Google Scholar

Copyright information

© Springer 2005

Authors and Affiliations

  1. 1.Department of Primary IndustriesJ.R. HirthVictoriaAustralia
  2. 2.Scottish Crop Research InstituteDundeeScotland
  3. 3.Department of Agricultural SciencesLa Trobe UniversityVictoriaAustralia

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