Plant and Soil

, Volume 254, Issue 2, pp 317–327

Turnover and distribution of root exudates of Zea mays

Article
  • 331 Downloads

Abstract

Decomposition and distribution of root exudates of Zea mays L. were studied by means of 14CO2 pulse labeling of shoots on a loamy Haplic Luvisol. Plants were grown in two-compartment pots, where the lower part was separated from the roots by monofilament gauze. Root hairs, but not roots, penetrated through the gauze into the lower part of the soil. The root-free soil in the lower compartment was either sterilized with cycloheximide and streptomycin or remained non-sterile. In order to investigate exudate distribution, 3 days after the 14C labeling, the lower soil part was frozen and sliced into 15, one-mm thick layers using a microtome. Cumulative 14CO2 efflux from the soil during the first 3 days after 14C pulse labeling did not change during plant growth and amounted to about 13–20% of the total recovered 14C (41–55% of the carbon translocated below ground). Nighttime rate of total CO2 efflux was 1.5 times lower than during daytime because of tight coupling of exudation with photosynthesis intensity. The average CO2 efflux from the soil with Zea mays was about 74 μg C g−1 day−1 (22 g C m−2 day−1), although, the contribution of plant roots to the total CO2 efflux from the soil was about 78%, and only 22% was respired from the soil organic matter. Zea mays transferred about 4 g m−2 of carbon under ground during 26 days of growth. Three zones of exudate concentrations were identified from the distribution of the 14C-activity in rhizosphere profiles after two labeling periods: (1) 1–2 (3) mm (maximal concentration of exudates) 2) 3–5 mm (presence of exudates is caused by their diffusion from the zone 1); (3) 6–10 mm (very insignificant amounts of exudates diffused from the previous zones). At the distance further than 10 mm no exudates were found. The calculated coefficient of exudate diffusion in the soil was 1.9 × 10−7 cm2 s−1.

14C pulse labeling exudate diffusion rhizosphere CO2 root exudates soil sterilization Zea mays 

Preview

Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

References

  1. Biddulph O 1969 Mechanisms of translocation of plant metabolites. In Physiological Aspects of Crop Yield. Eds. J D Eastin, F A Haskins, C Y Sullivan and C H N Van Bavel. pp. 143–164. Am. Soc. Agron. Crop. Sci. Soc. Am. Inc., Madison, WI.Google Scholar
  2. Black C A (Ed.) 1965 Methods of Soil Analysis, Part 2, pp. 1562–1565. Am. Soc. Agron., Inc. Publisher, Madison, WI.Google Scholar
  3. Boero G and Thien S 1979 Phosphatase activity and phosphorus availability in the rhizosphere. In The Soil Root Interface. Eds J L Harley and R S Russell. pp. 231–242, Academic Press, London.Google Scholar
  4. Bowen G D and Rovira A D 1976 Microbial colonization of plant roots. Annu. Rev. Phytopathol. 14, 121–144.Google Scholar
  5. Bowen G D and Theodorou C 1979 Interaction between bacteria and ectomycorrhizal fungi. Soil Biol. Biochem. 11, 119–126.CrossRefGoogle Scholar
  6. Cheng W, Coleman D C, Carroll C R and Hoffman C A 1993 In situ measurement of root respiration and soluble C concentrations in the rhizosphere. Soil Biol. Biochem. 25, 1189–1196.CrossRefGoogle Scholar
  7. Curl E A and Truelove B 1986 The Rhizosphere. Springer, Berlin.Google Scholar
  8. Darrah P R 1991a Measuring the diffusion coefficient of rhizosphere exudates in soil. I. The diffusion of non-sorbing compounds. J. Soil Sci. 42, 413–420.Google Scholar
  9. Darrah P R 1991b Measuring the diffusion coefficients of rhizosphere exudates in soil. I. The diffusion of sorbing compounds. J. Soil Sci. 42, 421–434.Google Scholar
  10. Darrah P R 1991c Models of the rhizosphere. II. A quasi three-dimensional simulation of the microbial population dynamics around a growing root releasing soluble exudates. Plant Soil 138, 147–158.Google Scholar
  11. Darrah P R 1991d Models of the rhizosphere. I. Microbial population dynamics around a root realising soluble and insoluble carbon. Plant Soil 133, 187–199.Google Scholar
  12. Deubel A 1996 Einfluss wurzelbürtiger organischer Kohlenstoffverbindungen auf Wachstum und Phosphatmobilisierung verschiedener Rhizosphärenbakterien. Dissertation, Martin-Luther-Universität Halle-Wittenberg.Google Scholar
  13. Deubel A, Gransee A and Merbach W 2000 Transformation of organic rhizodeposition by rhizosphere bacteria and its influence on the availability of tertiary calcium phosphate. J. Plant Nutr. Soil. Sci. 163, 387–392.Google Scholar
  14. 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.Google Scholar
  15. Domanski G, Kuzyakov Y, Siniakina SV, Stahr K 2001 Carbon flows in the rhizosphere of Lolium perenne. J. Plant Nutr. Soil Sci. 164, 381–387.Google Scholar
  16. Farr E, Vaidyanathan L V and Nye P H 1969 Measurement of ionic concentration gradients in soil near roots. Soil Sci. 107, 385–391.Google Scholar
  17. Gahoonia T S and Nielsen N E 1991 A method to study rhizosphere processes in thin soil layers of different proximity to roots. Plant Soil 135, 143–146.Google Scholar
  18. Gardner W K, Parbery D G, Barber D A and Swinden L 1983 The acquisition of phosphorus by Lupinus albus L.V. The diffusion of exudates away from roots: a computer simulation. Plant Soil 72, 13–29.Google Scholar
  19. Gransee A and Wittenmayer L 2000 Qualitative and quantitative analysis of water-soluble root exudates in relation to plant species and development. J. Plant Nutr. Soil. Sci. 163, 381–385.Google Scholar
  20. Gregory P J and Atwell B J 1991 The fate of carbon in pulse labelled crops of barley and wheat. Plant Soil 136, 205–213.Google Scholar
  21. Helal H M and Sauerbeck D 1983 Method of study turnover processes in soil layers of different proximity to roots. Soil Biol. Biochem. 15, 223–225.CrossRefGoogle Scholar
  22. Helal H M and Sauerbeck D 1986 Effect of plant roots on carbon metabolism of soil microbial biomass. Z. Pflanzenernähr. Bodenk. 149, 181–188.Google Scholar
  23. Kuchenbuch R and Jungk A 1982 A method for determining concentration profiles at the soil-root interface by thin slicing rhizosphere soil. Plant Soil 68, 391–394.Google Scholar
  24. Kuzyakov Y 1997 Abbau von mit 14C spezifisch markierten Aminosäuren im Boden und Decarboxylierung als einer der natürlichen Neutralisationmechanismen. Arch. Acker-Pflanzenbau Bodenk 41, 335–343.Google Scholar
  25. Kuzyakov Y 2002 Review: Factors affecting rhizosphere priming effects. J. Plant Nutr. Soil Sci. 165, 382–396.Google Scholar
  26. Kuzyakov Y and Cheng W 2001 Photosynthesis controls of rhizosphere respiration and organic matter decomposition. Soil Biol. Biochem. 33, 1915–1925.Google Scholar
  27. Kuzyakov Y and Demin V V 1998 CO2 efflux by rapid decomposition of low molecular organic substances in soils. Science of Soils, 3. http://link.springer.de/link/service/ journals /10112/fpapers /8003001/80030002.htm.Google Scholar
  28. Kuzyakov Y and Siniakina SV 2001 Siphon method of separating root-derived organic compounds from root respiration in non-sterile soil. J. Plant Nutr. Soil Sci. 164, 511–517.Google Scholar
  29. Kuzyakov Y, Kretzschmar A and Stahr K 1999 Contribution of Lolium perenne rhizodeposition to carbon turnover of pasture soil. Plant Soil 213, 127–136.Google Scholar
  30. Kuzyakov Y, Ehrensberger H and Stahr K 2001 Carbon partitioning and below-ground translocation by Lolium perenne. Soil Biol. Biochem. 33, 61–74.Google Scholar
  31. Liljeroth E, Kuikman P and Van Veen J A 1994 Carbon translocation to the rhizosphere of maize and wheat and influence on the turnover of native soil organic matter at different soil nitrogen levels. Plant Soil 161, 233–240.Google Scholar
  32. Lin Q and Brookes P S 1999 An evaluation of the substrate-induced respiration method. Soil Biol. Biochem. 31, 14, 1969–1983.Google Scholar
  33. Marschner H 1995 Mineral Nutrition of Higher Plants. 2nd Edition. Academic Press, London.Google Scholar
  34. Martens R 1990 Contribution of rhizodeposits to the maintenance and growth of soil microbial biomass. Soil Biol. Biochem. 22, 141–147.Google Scholar
  35. Martin J K 1977 Factors influencing the loss of organic carbon from wheat roots. Soil Biol. Biochem. 9, 1–7.Google Scholar
  36. Meharg A A and Killham K 1995 Loss of exudates from the roots of perennial ryegrass inoculated with a range of microorganisms. Plant Soil 170, 345–349.Google Scholar
  37. Merbach W and Ruppel S 1992 Influence of microbial colonization on 14CO2assimilation and amounts of root-borne 14C compounds in soil. Photosynthetica 26, 551–554.Google Scholar
  38. Merbach W, Mirus E, Knof G, Remus R, Ruppel S, Russow R, Gransee A and Schulze J 1999 Release of carbon and nitrogen compounds by plant roots and their possible ecological importance. J. Plant Nutr. Soil Sci. 162, 373–383.Google Scholar
  39. Moriarty D J W and Pollard P C 1982 Diel variation of bacterial productivity in seagrass (Zostera capricorni) beds measured by rate of thymidine incorporation in DNA. Mar. Biol. 72, 165–173Google Scholar
  40. Newman E I and Bowen H J 1974 Patterns of distribution of bacteria on root surface. Soil Biol. Biochem. 6, 205–209.Google Scholar
  41. Newman E I and Watson A 1977 Microbial abundance in the rhizosphere-a computer model. Plant Soil 48, 17–56.Google Scholar
  42. Norvell WA, Welch R M, Adams M L and Kochlan L V 1993 Reduction of Fe(III), Mn(III), and Cu(II) chelates by roots of pea (Pisum sativum L.) or soybean (Glycine max.). Plant Soil 155/156, 123–126.Google Scholar
  43. Nye P H and Tinker P B 1977 Solute Movement in the Soil-Root System. Blackwell Scientific Publications, Oxford.Google Scholar
  44. Paterson E and Sim A 1999 Rhizodeposition and C-partitioning of Lolium perenne in axenic culture affected by nitrogen supply and defoliation. Plant Soil 216, 155–164.Google Scholar
  45. Paul E A and Clark F E 1996 Soil Microbiology and Biochemistry. Academic Press, London.Google Scholar
  46. Rovira A D 1969 Plant root exudates. Bot. Rev. 35, 35–57.Google Scholar
  47. Rovira A D and Campbell R 1974 Scanning electron microscopy of microorganisms on the roots of wheat. Microbial Ecol. 1, 15–23.Google Scholar
  48. Sauerbeck D and Johnen B 1976 Der Umsatz von Pflanzenwurzeln im Laufe der Vegetationsperiode und dessen Beitrag zur ‘Bodenatmung'. Z. Pflanzenernähr. Bodenk. 3, 315–328.Google Scholar
  49. Schilling G, Gransee A, Deubel A, Lezovic G and Ruppel S 1998 Phosphorus availability, root exudates, and microbial activity in the rhizosphere. J. Plant Nutr. Soil Sci. 161, 465–478.Google Scholar
  50. Sposito G 1989 The Chemistry of Soils. Oxford University Press, Oxford.Google Scholar
  51. Swinnen J 1994 Evaluation of the use of a model rhizodeposition technique to separate root and microbial respiration in soil. Plant Soil 165, 89–101.Google Scholar
  52. Uren N C and Reisenauer H M 1988 The role of root exudates in nutrient acquisition. Adv. Plant Nutr. 3, 79–114.Google Scholar
  53. Veen B W 1980 Energy cost of ion transport. In Genetic Engineering of Osmoregulation. Impact on Plant Productivity for food, Chemicals and Energy. Eds D W Rains, R S Valentine and A Hollaender. pp. 187–195. Plenum Press, New York.Google Scholar
  54. Waremburg F R and Morral R A A 1978 Energy flow in the plant-microorganism system. In Interactions between Non-Pathogenic Soil Microorganisms and Plants. Eds Y R Dommergues and S V Krupa. pp. 205–242. Elsevier, Amsterdam.Google Scholar
  55. Welsh D T, Bourgues S, de Wit R and Aubi I 1997 Effect of plant photosynthesis, carbon sources and ammonium availability on nitrogen fixation rates in the rhizosphere of Zostera noltii. Aquat. Microb. Ecol. 12, 285–290.Google Scholar
  56. Whipps J M 1990 Carbon economy. In The Rhizosphere. Ed J M Lynch. pp. 59–97. John Wiley and Sons Ltd., Chichester.Google Scholar
  57. Zhang F S 1993 Mobilization of iron and manganese by plant-borne and synthetic metal chelators. Plant Soil 155/156, 111–114.Google Scholar

Copyright information

© Kluwer Academic Publishers 2003

Authors and Affiliations

  1. 1.Department of Soil Science and Land Evaluation, Institute of Soil Science and Land Evaluation (310)Hohenheim UniversityStuttgartGermany
  2. 2.Department of EcologyMoscow Agricultural AcademyMoscowRussia
  3. 3.Department of Soil ScienceInstitute of EcologyBerlinGermany

Personalised recommendations