Abstract
The mechanical and physiological bases for root growth against high mechanical impedance are reviewed. The best estimates of maximum axial root growth pressure (σmax) in completely impeded pea roots appear to be from 0.5 to 0.6 MPa, which results from a turgor pressure of about 0.8 MPa. When roots are incompletely impeded, a range of responses has been reported. Roots do not change elongation rate in a simple mechanical way in response to changes in mechanical impedance. Instead, ethylene might play a key role in mediating an increase in root diameter and a decrease in elongation rate. These changes persist for some hours or days after impedance is removed. Differences between species in their ability to penetrate strong soil layers are not related to differences in σmax, but appear to be due to differences in root diameter. In rice, differences between cultivars in the ability of their roots to penetrate strong wax layers are not related to their elongation rates through uniformly strong media. Differences between species or cultivars in their ability to penetrate strong layers may be due to differences in the tendency of roots to deflect or buckle when they grow from a weak to a strong environment.
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References
Abdalla A M, Hettiaratchi D R P and Reece A R 1969 The mechanics of root growth in granular media. J. Agric. Eng. Res. 14, 236–248.
Andrade A, Wolfe D W and Fereres E 1993 Leaf expansion, photosynthesis, and water relations of sunflower plants grown on compacted soil. Plant Soil 149, 175–184.
Atwell B J 1988 Physiological responses of lupin roots to soil compaction. Plant Soil 111, 277–281.
Atwell B J 1990 The effect of soil compaction on wheat during early tillering. II. Concentrations of cell constituents. New Phytol. 115, 37–41.
Atwell B J and Newsome J C 1990 Turgor pressure in mechanically impeded lupin roots. Aust. J. Plant Physiol. 17, 49–56.
Babalola O and Lal R 1977 Subsoil gravel horizon and maize root growth. I. Gravel concentration and bulk density effects. Plant Soil 46, 337–346.
Baluška F, Brailsford R W, Hauskrecht M, Jackson M B and Barlow PW 1993 Cellular dimorphism in the maize root cortex: involvement of microtubules, ethylene and gibberellin in the differentiation of cellular behaviour in postmitotic growth zones. Bot. Acta 106, 394–403.
Barley K P and Greacen E L 1967 Mechanical resistance as a soil factor influencing the growth of roots and underground shoots. Adv. Agron. 19, 1–40.
Barraclough P B and Weir A H 1988 Effects of a compacted subsoil layer on root and shoot growth, water use and nutrient uptake of winter wheat. J. Agric. Sci. 110, 207–216.
Bengough A G, Croser C and Pritchard J 1997 A biophysical analysis of root growth under mechanical stress. Plant Soil 189, 155–164.
Bengough A G and Kirby J M 1999 Tribology of the root cap in maize (Zea mays) and peas (Pisum sativum). New Phytol. 142, 421–425.
Bengough A G, Mackenzie C J and Elangwe H E 1994 Biophysics of the growth responses of pea roots to changes in penetration resistance. Plant Soil 167, 135–141.
Bengough A G and McKenzie B M 1997 Sloughing of root cap cells decreases the frictional resistance to maize (Zea mays L.) root growth. J. Exp. Bot. 48, 885–893.
Bengough A G and Mullins C E 1990 Mechanical impedance to root growth: a review of experimental techniques and root growth responses. J. Soil Sci. 41, 341–358.
Bengough A G and Mullins C E 1991 Penetrometer resistance, root penetration resistance and root elongation rate in two sandy loam soils. Plant Soil 131, 59–66.
Bengough A G and Young I M 1993 Root elongation of seedling peas through layered soil of different penetration resistances. Plant Soil 149, 129–139.
Bingham I J 2001 Soil–root–canopy interactions. Ann. Appl. Biol. 138, 243–251.
Bushamuka V N and Zobel R W 1998 Differential genotypic and root type penetration of compacted soil layers. Crop Sci. 38, 776–781.
Clark L J, Aphalé S L and Barraclough P B 2000 Screening the ability of rice roots to overcome the mechanical impedance of wax layers: importance of test conditions and measurement criteria. Plant Soil 219, 187–196.
Clark L J and Barraclough P B 1999 Do dicotyledons generate greater maximum axial root growth pressures than monocotyledons? J. Exp. Bot. 50, 1263–1266.
Clark L J, Bengough A G, Whalley W R, Dexter A R and Barraclough P B 1999 Maximum axial root growth pressure in pea seedlings: effects of measurement techniques and cultivars. Plant Soil 209, 101–109.
Clark L J, Cope R E, Whalley W R, Barraclough P B and Wade L J 2002 Root penetration of strong soil in rainfed lowland rice: comparison of laboratory screens with field performance. Field Crops Res. 76, 189–198.
Clark L J, Whalley W R and Barraclough P B 2001 Partial mechanical impedance can increase the turgor of seedling pea roots. J. Exp. Bot. 52, 167–171.
Clark L J, Whalley W R, Dexter A R, Barraclough P B and Leigh R A 1996 Complete mechanical impedance increases the turgor of cells in the apex of pea roots. Plant Cell Environ. 19, 1099–1102.
Clark R B, Alberts E E, Zobel R W, Sinclair T R, Miller M S, Kemper W D and Foy C D 1998 Eastern gamagrass (Tripsacum dactyloides) root penetration into and chemical properties of claypan soils. Plant Soil 200, 33–45.
Cosgrove D J 1993 Tansley Review No. 46. Wall extensibility: its nature, measurement and relationship to plant cell growth. New Phytol. 124, 1–23.
Croser C, Bengough A G and Pritchard J 2000a The effect of mechanical impedance on root growth in pea (Pisum sativum). I. Rates of cell flux, mitosis, and strain during recovery. Physiol. Plant. 107, 277–286.
Croser C, Bengough A G and Pritchard J 2000b The effect of mechanical impedance on root growth in pea (Pisum sativum). II. Cell expansion and wall rheology during recovery. Physiol. Plant. 109, 150–159.
Dexter A R and Hewitt J S 1978 The deflection of plant roots. J. Agric. Engng Res. 23, 17–22.
Eavis B W 1967 Mechanical impedance and root growth. Symp. Inst. Agric. Eng., Silsoe UK, 4/F/39, 1–11.
Eavis B W, Ratliff L F and Taylor H M 1969 Use of a dead-load technique to determine axial root growth pressure. Agron. J. 61, 640–643.
Frensch J and Hsiao T C 1995 Rapid response of the yield threshold and turgor regulation during adjustment of root growth to water stress in Zea mays. Plant Physiol. 108, 303–312.
Gill W R and Bolt G H 1955 Pfeffer's 31 studies of the root growth pressures exerted by plants. Agron. J. 47, 166–168.
Goss M J 1977 Effects of mechanical impedance on root growth in barley (Hordeum vulgare L.). I. Effects on the elongation and branching of seminal root axes. J. Exp. Bot. 28, 96–111.
Goss M J and Scott Russell R 1980 Effects of mechanical impedance on root growth in barley (Hordeum vulgare L.). III. Observations on the mechanism of response. J. Exp. Bot. 31, 577–588.
Greacen E L 1986 Root response to soil mechanical properties. Trans. 13th Congress Int. Soc. Soil Sci. 5, 20–47.
Greacen E L and Oh J S 1972 Physics of root growth. Nature New Biol. 235, 24–25.
Hartung W, Zhang J and Davies W J 1994 Does abscisic acid play a stress physiological role in maize plants growing in heavily compacted soil? J. Exp. Bot. 45, 221–226.
He C, Finlayson S A, Drew M C, Jordan W R and Morgan P W 1996 Ethylene biosynthesis during aerenchyma formation in roots of maize subjected to mechanical impedance and hypoxia. Plant Physiol. 112, 1679–1685.
Henderson C W L 1989. Lupin as a biological plough: evidence for and effects on wheat growth and yield. Aust. J. Exp. Agric. 29, 99–102.
Hussain A, Black C R, Taylor I B, Mulholland B J and Roberts J A 1999 Novel approaches for examining the effects of differential soil compaction on xylem sap abscisic acid concentration, stomatal conductance and growth in barley (Hordeum vulgare L.). Plant Cell Environ. 22, 1377–1388.
Hussain A, Black C R, Taylor I B and Roberts J A 2000 Does an antagonistic relationship between ABA and ethylene mediate shoot growth when tomato (Lycopersicon esculentum Mill.) plants encounter compacted soil? Plant Cell Environ. 23, 1217–1226.
Iijima M, Griffiths B and Bengough A G 2000 Sloughing of cap cells and carbon exudation from maize seedling roots in compacted sand. New Phytol. 145, 477–482.
Iijima M and Kono Y 1992 Development of Golgi apparatus in the root cap cells of maize (Zea mays L.) as affected by compacted soil. Ann. Bot. 70, 207–212.
IijimaM, Kono Y, Yamauchi A and Pardales J R 1991 Effects of soil compaction on the development of rice and maize root systems. Environ. Exp. Bot. 31, 333–342.
Kundu D K, Ladha J K and Lapitan de Guzman E 1996 Tillage depth influence on soil nitrogen distribution and availability in a rice lowland. Soil Sci. Soc. Am. J. 60, 1153–59.
Lachno D R, Harrison-Murray R S and Audus L J 1982 The effects of mechanical impedance to growth on the levels of ABA and IAA in root tips of Zea mays L. J. Exp. Bot. 33, 943–951.
Lockhart J A 1965 An analysis of irreversible plant cell elongation. J. Theor. Biol. 8, 264–275.
Masle J and Passioura J B 1987 The effect of soil strength on the growth of young wheat plants. Aust. J. Plant Physiol. 14, 643–56.
Materechera S A, Alston A M, Kirby J M and Dexter A R 1992 Influence of root diameter on the penetration of seminal roots into a compacted subsoil. Plant Soil 144, 297–303.
Materechera S A, Dexter A R and Alston A M 1991 Penetration of very strong soils by seedling roots of different plant species. Plant Soil 135, 31–41.
May O L and Kasperbauer M J 1999 Genotypic variation for root penetration of a soil pan. J. Sustain. Agric. 13, 87–94.
McEwen J and Johnston A E 1979 The effects of subsoiling and deep incorporation of P and K fertilizers on the yield and nutrient uptake of barley, potatoes, wheat and sugar beet grown in rotation. J. Agric. Sci. Camb. 92, 695–702.
Misra R K 1997 Maximum axial growth pressures of the lateral roots of pea and eucalypt. Plant Soil 188, 161–170.
Misra R K, Dexter A R and Alston A M 1986a Maximum axial and radial growth pressures of plant roots. Plant Soil 95, 315–326.
Misra R K, Dexter A R and Alston A M 1986b Penetration of soil aggregates of finite size. II. Plant roots. Plant Soil 94, 59–85.
Misra R K and Gibbons A K 1996 Growth and morphology of eucalypt seedling-roots, in relation to soil strength arising from compaction. Plant Soil 182, 1–11.
Montagu K D, Conroy J P and Atwell B J 2001 The position of localized soil compaction determines root and subsequent shoot growth responses. J. Exp. Bot. 52, 2127–2133.
Moss G I, Hall K C and Jackson M B 1988 Ethylene and the responses of roots of maize (Zea mays L.) to physical impedance. New Phytol. 109, 303–311.
Mulholland B J, Black C R, Taylor I B, Roberts J A and Lenton J R 1996a Effect of soil compaction on barley (Hordeum vulgare L.) growth. I. Possible role for ABA as a root-sourced chemical signal. J. Exp. Bot. 47, 539–549.
Mulholland B J, Taylor I B, Black C R and Roberts J A 1996b Effect of soil compaction on barley (Hordeum vulgare L.) growth. II. Are increased xylem sap ABA concentrations involved in maintaining leaf expansion in compacted soils? J. Exp. Bot. 47, 551–556.
Mullins C E, Blackwell P S and Tisdall J M 1992 Strength development during drying of a cultivated, flood-irrigated hardsetting soil. I. Comparison with a structurally stable soil. Soil Tillage Res. 25, 113–128.
Mutsaers H J W, Weber G K, Walker P and Fisher N M 1997 A field guide for on-farm experimentation. IITA/CTA/ISNAR.
Osborne D J 1976 Control of cell shape and cell size by the dual recognition of auxin and ethylene. In Perspectives in Experimental Biology, Vol. 2. Ed. N. Sunderland, pp. 89–102. Pergamon, Oxford.
Price A H, Steele K A, Moore B J, Barraclough P B and Clark L J 2000 A combined RFLP and AFLP linkage map of upland rice (Oryza sativa L.) used to identify QTLs for root-penetration ability. Theor. Appl. Genet. 100, 49–56.
Pritchard J, Barlow P W, Adam J S and Tomos A D 1990 Biophysics of the inhibition of the growth of maize roots by lowered temperature. Plant Physiol. 93, 222–230.
Probine M C and Preston R D 1962 Cell growth and the structure and mechanical properties of the wall in internodal cells of Nitella opaca. II. Mechanical properties of the walls. J. Exp. Bot. 13, 111–127.
Rasse D P and Smucker A J M 1998 Root recolonization of previous root channels in corn and alfalfa rotations. Plant Soil 204, 203–213.
Roberts J A, Hussain A, Taylor I B and Black C R 2002 Use of mutants to study long-distance signalling in response to compacted soil. J. Exp. Bot. 53, 45–50.
Sarquis J I, Jordan W R and Morgan P W 1991 Ethylene evolution from maize (Zea mays L.) seedling roots and shoots in response to mechanical impedance. Plant Physiol. 96, 1171–1177.
Sarquis J I, Morgan P W and Jordan W R 1992 Metabolism of 1-aminocyclopropane-1-carboxylic acid in etiolated maize seedlings grown under mechanical impedance. Plant Physiol. 98, 1342–1348.
Schmidt C P and Belford R K 1994 Increasing the depth of soil disturbance increases yields of direct drilled wheat on the sandplain soils of Western Australia. Aust. J. Exp. Agric. 34, 777–781.
Scholefield D and Hall D M 1985 Constricted growth of grass roots through rigid pores. Plant Soil 85, 153–162.
Sharma PK, Ingram KT and Harnpichitvitaya D 1995 Subsoil compaction to improve water use efficiency and yields of rainfed lowland rice in coarse-textured soils. Soil Tillage Res. 36, 33–44.
Sharp R E 2002 Interaction with ethylene: changing views on the role of abscisic acid in root and shoot growth responses to water stress. Plant Cell Environ. 25, 211–222.
Sharp R E, Silk W K and Hsiao T C 1988 Growth of the maize primary root at low water potentials. I. Spatial distribution of expansive growth. Plant Physiol. 87, 50–57.
Stolzy L H and Barley K P 1968 Mechanical resistance encountered by roots entering compact soils. Soil Sci. 105, 297–301.
Tardieu F 1988 Analysis of the spatial variability of maize root density. III. Effect of a wheel compaction on water extraction. Plant Soil 109, 257–262.
Tardieu F, Katerji N, Bethenod O, Zhang J and Davies W J 1991 Maize stomatal conductance in the field: its relationship with soil and plant water potentials, mechanical constraints and ABA concentration in the xylem sap. Plant Cell Environ. 14, 121–126.
Taylor H M and Ratliff L F 1969 Root growth pressures of cotton, peas and peanuts. Agron. J. 61, 398–402.
Tomos D and Pritchard J 1994 Biophysical and biochemical control of cell expansion in roots and leaves. J. Exp. Bot. 45, 1721–1731.
Veen B W 1982 The influence of mechanical impedance on the growth of maize roots. Plant Soil 66, 101–109.
Wade L J 1996 Soil compaction – make it or break it for rainfed lowland ecosystem. In Management of Clay Soils in the Rainfed Lowland Rice-Based Cropping System. pp. 243–247. Proceedings Number 70, ACIAR, Canberra.
Wiersum L K 1957 The relationship of the size and structural rigidity of pores to their penetration by roots. Plant Soil 9, 75–85.
Whalley W R, Bengough A G and Dexter A R 1998 Water stress induced by PEG decreases the maximum growth pressure of the roots of pea seedlings. J. Exp. Bot. 49, 1689–1694.
Whalley W R, Clark L J and Dexter A R 1994 The temperaturedependence of the maximum axial growth pressure of roots of pea (Pisum sativum L.). Plant Soil 163, 211–215.
Whalley W R, Lipiec J, Stepniewski W and Tardieu F 2000 Control and measurement of the physical environment in root growth experiments. In Root Methods: a Handbook. Eds. A L Smit, A G Bengough, C Engels, M van Noordwijk, S Pellerin and S C van de Geijn. pp. 75–112. Springer, Berlin.
Whiteley G M and Dexter A R 1982 Root development and growth of oilseed, wheat and pea crops on tilled and non-tilled soil. Soil Tillage Res. 2, 379–393.
Whiteley G M, Hewitt J S and Dexter A R 1982 The buckling of plant roots. Physiol. Plant 54, 333–342.
Whiteley G M, Utomo W H and Dexter A R 1981 A comparison of penetrometer pressures and the pressures exerted by roots. Plant Soil 61, 351–364.
Yu L, Ray J D, O'Toole J C and Nguyen H T 1995 Use of waxpetrolatum layers for screening rice root penetration. Crop Sci. 35, 684–687.
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Clark, L., Whalley, W. & Barraclough, P. How do roots penetrate strong soil?. Plant and Soil 255, 93–104 (2003). https://doi.org/10.1023/A:1026140122848
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DOI: https://doi.org/10.1023/A:1026140122848