Abstract
The responses of roots to nitrogen- and phosphorus-rich patches of soil include proliferation of laterals and stimulation of nutrient inflow (uptake rate per unit root length) within the patch. Nitrate uptake from an N-rich patch is thereby maximised and, perhaps, compensates for an uneven supply of nitrate to the whole root system. Paradoxically, the often weak correlation between root length density and N uptake found in experiments on single plants and crop monocultures suggests that root proliferation in patches has only a minor compensatory influence on N capture. This paradox was resolved when it was realised that localised root proliferation during inter-specific competition for nitrate can lead to a strong association between root length density and nitrate capture. Here, a simple model of inter-specific competition is used to estimate the stimulation in inflow required in one plant to match the N capture of a competitor that responds only by root proliferation, and to estimate associated carbon costs. The model predicts that nitrate inflow must increase proportionally more than root length density to achieve the same N capture. For example, the N capture possible with a 10% increase in root length density can be matched by increasing N inflow by anything from 20% to 20-fold, depending on the initial conditions: the faster the rate of change in root length density, the greater the required relative increase in inflow. In those terms, proliferation would seem the better option, but one that may be more costly in terms of its carbon requirement.
This is a preview of subscription content, log in via an institution.
Buying options
Tax calculation will be finalised at checkout
Purchases are for personal use only
Learn about institutional subscriptionsPreview
Unable to display preview. Download preview PDF.
References
Bilborough C J and Caldwell M M 1995 The effects of shading and N status on root proliferation in nutrient patches by the perennial grass Agropyron desertorum. Oecologia 103, 19–16.
Boot R G A and Mensink M (1990) Size and morphology of root systems of perennial grasses from contrasting habitats as affected by nitrogen supply Plant Soil 129, 291–299.
Campbell B D and Grime J P 1989 A comparative study of plant responsiveness to the duration of episodes of mineral nutrient enrichment. New Phytol. 112, 261–267.
Cui M and Caldwell M M 1997 Shading reduces exploitation of soil nitrate and phosphate by Agropyron desertorum and Artemisia tridentata from soils with patchy and uniform nutrient distributions. Oecologia 109, 177–183.
Drew M C and Saker L R 1975 Nutrient supply and the growth of the seminal root system in barley. II. Localized, compensatory increases in lateral root growth and rates of nitrate uptake when nitrate supply is restricted to only part of the root system. J. Exp. Bot. 26, 79–90.
Drew M C and Saker L R 1978 Nutrient supply and the growth of the seminal root system in barley. III. Compensatory increases in growth of lateral roots, and in rates of phosphate uptake, in response to a localized supply of phosphate. J. Exp. Bot. 29, 435–451.
Drew M C, Saker L R and Ashley T W 1973 Nutrient supply and the growth of the seminal root system in barley. I. The effect of nitrate concentration on the growth of axes and laterals. J. Exp. Bot. 24, 1189–1202.
Eissenstat D M and Yanai R D 1997 The ecology of root lifespan. Adv. Ecol. Res. 27, 1–60.
Forde B G 2000 Nitrate transporters in plants: structure, function and regulation. Biochim. Biophys. Acta Biomembranes 1465, 219–235.
Forde B G and Clarkson D T 1999 Nitrate and ammonium nutrition of plants: physiological and molecular perspectives. Adv. Bot. Res. 30, 1–90.
Hodge A, Stewart J, Robinson D, Griffiths B S and Fitter A H 1998 Root proliferation, soil fauna and plant nitrogen capture from nutrient-rich patches in soil. New Phytol. 139, 479–494.
Hodge A, Robinson D, Griffiths B S and Fitter A H 1999 Why plants bother: root proliferation results in increased nitrogen capture from a nutrient-rich patch when two grasses compete. Plant Cell Environ. 22, 811–820.
Hodge A, Robinson D and Fitter A H 2000 An arbuscular mycorrhizal inoculum enhances root proliferation in, but not nitrogen capture from, nutrient-rich patches in soil. New Phytol. 145, 575–584.
Howitt S M and Udvardi M K 2000 Structure, function and regulation of ammonium transporters in plants. Biochim. Biophys. Acta Biomembranes 1465, 152–170.
Jackson R B and Caldwell M M 1996 Integrating resource heterogeneity and plant plasticity: modelling nitrate and phosphate uptake in a patchy soil environment. J. Ecol. 84, 891–903.
Lamers H, Chapin F S and Pons T L 1998 Plant Physiological Ecology. Springer, Berlin. 540 p.
Lappartient A G, Vidmar J J, Leustek T, Glass A D M and Touraine B 1999 Inter-organ signaling in plants: regulation of ATP sulfurylase and sulfate transporter genes expression in roots, mediated by pholem-translocated compound. Plant J. 18, 89–95.
Nobel P S 1991 Physicochemical and Environmental Plant Physiology. Academic Press, San Diego, CA 635 p.
Otani T and Ae N 1996 Sensitivity of phosphorus uptake to changes in root length and soil volume. Agron. J. 88, 371–375.
Pregitzer K S, Hendrick R L and Fogel R 1993 The demography of fine roots in response to patches of water and nitrogen. New Phytol. 125, 575–580.
Robinson D 1986 Limits to nutrient inflow rates in roots and root systems. Physiol. Plant. 68, 551–559.
Robinson D 1994 The responses of plants to non-uniform supplies of nutrients. New Phytol. 127, 635–674.
Robinson D 1996a Variation, co-ordination and compensation in root systems in relation to soil variability. Plant Soil 187, 57–66.
Robinson D 1996b Resource capture by localised root proliferation: why do plants bother? Ann. Bot. 77, 179–185.
Robinson D and Rorison I H 1983 A comparison between the responses of Lolium perenne L., Holcus lanatus L. and Deschampsia flexuosa (L.) Trin. to a localized supply of nitrogen. New Phytol. 94, 263–273.
Robinson D, Linehan D J and Gordon D C 1994 Capture of nitrate from soil by wheat in relation to root length, nitrogen inflow and availability. New Phytol. 128, 297–305.
Robinson D and Van Vuuren M M I 1998 Responses of wild plants to nutrient patches in relation to growth rate and life-form. In Inherent Variation in Plant Growth. Physiological Mechanisms and Ecological Consequences. Eds H Lambers, H Poorter and M M I Van Vuuren. pp. 237–257. Backhuys Publishers, Leiden.
Robinson D, Hodge A, Griffiths B S and Fitter A H 1999 Plant root proliferation in nitrogen-rich patches confers competitive advantage. Proc. R. Soc. London B 266: 431–435.
Scheurwater I, Clarkson D T, Purves J V, Van Rijt G, Saker L R, Welschen R and Lambers H 1999 Relatively large nitrate efflux can account for the high specific respiratory costs for nitrate transport in slow-growing grass species. Plant Soil 215, 123–134.
Tibbett M 2000 Roots, foraging and the exploitation of soil nutrient patches: the role of mycorrhizal symbiosis. Funct. Ecol. 14, 397–399.
Tinker P B, Nye P H 2000 Solute Movement in the Rhizosphere. Oxford University Press, Oxford. 444 pp.
Van Vuuren M M I, Robinson D and Griffiths B S 1996 Nutrient inflow and root proliferation during the exploitation of a temporally and spatially discrete source of nitrogen in soil. Plant Soil 178, 185–192.
Vidmar J J, Tagmount A, Cathala N, Touraine B and Davidian J C E 2000 Cloning and characterization of a root specific high-affinity sulfate transporter from Arabidopsis thaliana. FEBS Lett. 475, 65–69.
Wiesler F and Horst W J 1994 Root growth and nitrate utilization of maize cultivars under field conditions. Plant Soil 163, 267–277.
Yanai J, Linehan D J, Robinson D, Young I M, Hackett C A, Kyuma K and Kosaki T. 1995 Effects of inorganic nitrogen application on the dynamics of the soil solution composition in the root zone of maize in a Scottish soil. Plant Soil 180, 1–9.
Zhang H and Forde B G 1998 An Arabidopsis MADS box gene that controls nutrient-induced changes in root architecture. Science 279, 407–409.
Zhang H, Jennings A, Barlow P W and Forde B G 1999 Dual pathways for regulation of root branching by nitrate. Proc. Natl. Acad. Sci. USA 96, 6529–6534.
Author information
Authors and Affiliations
Editor information
Rights and permissions
Copyright information
© 2002 Springer Science+Business Media Dordrecht
About this chapter
Cite this chapter
Robinson, D. (2002). Root proliferation, nitrate inflow and their carbon costs during nitrogen capture by competing plants in patchy soil. In: Powlson, D.S., Bateman, G.L., Davies, K.G., Gaunt, J.L., Hirsch, P.R. (eds) Interactions in the Root Environment: An Integrated Approach. Developments in Plant and Soil Sciences, vol 96. Springer, Dordrecht. https://doi.org/10.1007/978-94-010-0566-1_5
Download citation
DOI: https://doi.org/10.1007/978-94-010-0566-1_5
Publisher Name: Springer, Dordrecht
Print ISBN: 978-94-010-3925-3
Online ISBN: 978-94-010-0566-1
eBook Packages: Springer Book Archive