Abstract
The role of organic acids in the mobilization of plant nutrients from the rhizosphere was assessed in seven contrasting soil types. The results indicated that malate was poor at mobilizing micronutrients from all the test soils, whilst citrate was capable of mobilizing significant quantities. Citrate was also capable of mobilizing P from one soil which possessed a large Ca-P fraction. This mobilization of P was due to both the complexing action of the citrate anion and due to the dissolution properties of the protons released from citric acid upon equilibrium with the soil solution. The reaction of citrate with cations was found to be near instantaneous with significant absorption to the solid phase in some soils at low concentrations. Soil decomposition studies indicated that citrate was rapidly broken down in organic soils but was more resistant to degradation in subsoil horizons. It was concluded that organic acids can be expected to be of little consequence in nutrient mobilization from high pH soils, whilst in acid soils they may be involved both in a more general mechanism for micronutrient uptake or as a potential Al detoxification mechanism.
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Abbreviations
- C6H8O7 :
-
Citric acid and H-citrate indicates
- C6H5O7Na3 :
-
whilst Na-citrate indicates
References
Avery B W 1973 Soil classification in the soil survey of England and Wales. J. Soil Sci. 24, 324–328.
Barber S A 1984 Soil Nutrient Biovailability: A Mechanistic Approach. Wiley, New York, USA. 398p.
Chen Y and Hadar Y 1991 Iron nutrition and interactions in plants. Developments in Plant and Soil Science Vol 43. Kluwer Academic, Netherlands. 3/7 p.
Cline G R, Powell P E, Szaniszlo P J and Reid C P P 1987 Comparison of the abilities of hydroxamic, synthetic and other natural organic acids to chelate Fe and other ions in nutrient solution. Soil Sci. Soc. Am. J. 46, 1158–1164.
Curl E A and Trueglove B 1986 The Rhizosphere, Springer-Verlag, Berlin, Germany.
Darrah P R 1991 Measuring the diffusion coefficients of rhizosphere exudates in soil II. The diffusion of sorbing compounds. J. Soil Sci. 42, 421–436.
Dinkelaker B, Römheld V and Marschner H 1989 Citric acid excretion and precipitation of calcium citrate in the rhizosphere of white lupin (Lupinus albus L.). Plant Cell Environ. 12, 285–292.
Earl K D, Syers J K and McLaughlin J R 1979 Origin of effects of citrate, tartrate, and acetate on phosphate sorption by soils and synthetic gels. Soil Sci. Soc. Am. J. 43, 674–678.
Fitzpatrick E A 1983 Soils, their classification and distribution. Longman Inc., New York, USA. 353 p.
Fox T R, Comerford N B and McFee W W 1990 Phosphorus and aluminum release from a spodic horizon mediated by organic acids. Soil Sci. Soc. Am. J. 54, 1763–1767.
Gardner W K, Barber D A and Parbery D G 1983 The acquistion of phosphorus by Lupinus albus L. III. The probable mechanism by which phosphorus movement in the soil/root interface is enhanced. Plant and Soil 70, 107–124.
Hoffland E 1992 Quantitative evaluation of the role of organic acid exudation in the mobilization of rock phosphate by rape. Plant and Soil 140, 179–289.
Hoffland E, Findenegg G R and Nelemans J A 1989 Solubilization of rock phosphate by rape. II. Local root exudation of organic acids as a response to P starvation. Plant and Soil 113, 161–165.
Hue N V, Craddock G R and Adams F 1986 Effect of organic acids on aluminum toxicity in subsoils. Soil Sci. Soc. Am. J. 50, 28–34.
Jones D L and Darrah P R 1992 Re-sorption of organic compounds by roots of Zea mays L. and its consequences in the rhizosphere I. Re-sorption of 14C labelled glucose, mannose and citric acid. Plant and Soil 143, 259–266.
Jones D L and Darrah P R 1993a Re-sorption of organic compounds by roots of Zea mays L. and its consequences in the rhizosphere II. Experimental and model evidence for simultaneous exudation and re-sorption of compounds. Plant and Soil 153, 47–59.
Jones D L and Darrah P R 1993b Influx and efflux of amino acids from Zea mays L. roots and their implications for N nutrition and the rhizosphere. In Plant Nutrition — From Genetic Engineering to Field Practice. Ed. N JBarrow. pp 91–94. Kluwer Academic Publishers, Dordrecht, The Netherlands.
Jones D L and Darrah P R 1994 Influx and efflux of organic acids across the root-soil interface of Zea mays L. and its implications in rhizosphere C flow and mineral nutrition. Plant and Soil (Submitted).
Jones D L, Edwards A C, Donachie K and Darrah P R 1994 Role of proteinaceous amino-acids released in root exudates in nutrient acquisition from the rhizosphere. Plant and Soil 158, 183–192.
Lindsay W L 1979 Chemical equilibria in soils. Wiley-Interscience, New York, USA.
Lopez-Hernadez D, Siegert G and Rodriguez JV, 1986 Competitive adsorption of phosphate with malate and oxalate by tropical soils. Soil Sci. Soc. Am. J. 50, 1460–1462.
Lundström U S 1993 The role of organic acids in the soil solution chemistry of a podsolized soil. J. Soil Sci. 44, 121–133.
Majdi H and Persson H 1993 Spatial distribution of fine roots, rhizosphere and bulk-soil chemistry in an acidified Picea abies stand. Scand. J. For. Res. 8, 147–155.
Marschner H 1986 Mineral Nutrition in Higher Plants. Academic Press, London.
Merckx R, VanGinkel J H, Sinnaeve J and Cremers A 1986 Plant-induced changes in the rhizosphere of maize and wheat. II. Complexation of cobalt, zinc and manganese in the rhizosphere of maize and wheat. Plant and Soil 96, 95–107.
Mori S, Nishizawa N, Hayashi H, Chino M, Yoshimura E and Ishihara J 1991 Why are young rice plants highly susceptible to iron deficiency? Plant and Soil 130, 143–356.
Martell A E and Smith R M 1976–1989 Critical stability constants, 6 volumes. Plenum Press, New York.
Miyasaka S C, Buta J C, Howell R K and Foy C D 1991 Mechanisms of Al tolerance in snapbeans. Root exudation of citric acid. Plant Physiol. 96, 737–743.
Murphy J and Riley J P 1962 A modified single solution method for the determination of phosphate in natural waters. Anal. Chim. Acta 27, 31–36.
Olsen S R and Sommers L E 1982 Phosphorus. In Methods of Soil Analysis Part 2. Eds. A LPage, K HMiller and D RKeeney. pp 414–416. American Society of Agronomy Publications, Madison, Wisconsin, USA.
Parker D R, Zelazny L W and Kinraide T B 1989 Chemical speciation and plant toxicity of aqueous aluminium. In Environmental Chemistry and Toxicology of Aluminium. Ed. T ELewis. pp 117–145. Lewis Publications, Chelsea, MI.
Pohlman A A and McColl J G 1986 Kinetics of metal dissolution from forest soils by coluble organic acids. J. Environ. Qual. 15, 86–92
Takagi S, Nomoto K and Takemoto T 1984 Physiological aspect of mugineic acid, a possible phytosiderophore of graminaceous plants. J. Plant Nutr. 71, 469–477
Uren N C and Reisenauer H M 1988 The role of root exudates in nutrient acquisition. Adv. Plant Nutr. 3, 79–114.
Welch R M, Norvell W A, Schaefer S C, Shaff J E and Kochian L V 1993 Induction of iron(III) and copper (II) reduction in pea (Pisum sativum L.) roots by Fe and Cu status: Does the root-cell plasmalemma Fe(III)-chelate reductase perform a general role in regulating cation uptake? Planta 190, 555–561.
Whipps J M 1990 Carbon Economy. In The Rhizosphere, Ed. J MLynch. pp 59–97. Wiley Interscience, London.
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Jones, D.L., Darrah, P.R. Role of root derived organic acids in the mobilization of nutrients from the rhizosphere. Plant Soil 166, 247–257 (1994). https://doi.org/10.1007/BF00008338
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DOI: https://doi.org/10.1007/BF00008338