Skip to main content
Log in

Modulation of NO -3 uptake by water-extractable humic substances: involvement of root plasma membrane H+ATPase

  • Published:
Plant and Soil Aims and scope Submit manuscript

Abstract

The effect of a water extractable humic substances fraction (WEHS) on nitrate uptake and plasma membrane (pm) H+-ATPase activity of maize roots was investigated. Four days old maize root seedlings were exposed for 4 to 24 h to a nutrient solution containing 200 μ M nitrate in the absence or presence of 5 mg org. C { L -1 WEHS. Plants exposed to nitrate developed a higher capacity to absorb the anion (induction): the net uptake rate progressively increased up to 12 h of contact with the solution; thereafter, a decline was observed. When WEHS was present together with nitrate in the nutrient solution, the induction of nitrate uptake was evident and maximal already 4 h after starting the treatment. The rate of net nitrate uptake decreased only slightly during the remaining period (4-24 h). Stimulation of net nitrate uptake rate was also observed when WEHS was added to a nitrogen- or nitrate-free nutrient solution or to a 5 mM CaSO4 solution. The activity of pmH+-ATPase raised upon exposure of the roots to nitrate with the same pattern observed for nitrate uptake. The contemporary presence of nitrate and WEHS caused a further stimulation of the pmH+-ATPase activity after 4 h treatment. An increase in the enzyme activity was also observed when plants were treated for 4 h in the presence of WEHS in CaSO4, nitrogen- or nitrate-free solutions. However, when nitrate was present the enhancement was even greater. Results support the idea that the plasma membrane proton pump might be one of the primary targets of the action of humic substances on plant nutrient acquisition. A role of WEHS in the modulation of nitrate uptake via an interaction with the pm H+-ATPase is also discussed.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Institutional subscriptions

Similar content being viewed by others

References

  • Aiken GR, Thurman EM and Malcolm RL 1979 Comparison of XAD macroporus resin for the concentration of fulvic acid from aqueous solution. Anal. Chem. 51, 1799-1803.

    Article  CAS  Google Scholar 

  • Albuzio A, Ferrari G and Nardi S 1986 Effects of humic substances on nitrate uptake and assimilation in barley seedlings. Can. J. Soil Sci. 66, 731-736.

    Article  CAS  Google Scholar 

  • Bradford MM 1976 A rapid and sensitive method of quantitation of microgram quantities of protein utilizing the principle of proteindye binding. Anal. Biochem. 72, 248-254.

    Article  PubMed  CAS  Google Scholar 

  • Cataldo DA, Haroon M, Schrader LB and Youngs VI 1975 Rapid colorimetric determination of nitrate in plant tissues by nitratation of salicylic acid. Comm. Soil Sci. Plant Anal. 6, 71-80.

    CAS  Google Scholar 

  • Crawford NM 1995 Nitrate: nutrient and signal for plant growth. Plant Cell 7, 859-868.

    Article  PubMed  CAS  Google Scholar 

  • Crawford NM and Glass ADM 1998 Molecular and physiological aspects of nitrate uptake in plants. Trends Plant Sci. 3, 389-395.

    Article  Google Scholar 

  • Dell'Agnola G and Nardi S 1987 Hormone-like effect and enhanced nitrate uptake induced by depolycondensed humic fractions obtained from Allolobophora rosea and A. caliginosa faeces. Biol. Fertil. Soils 4, 115-118.

    Article  Google Scholar 

  • Fischer-Schliebs E, Varanini Z and Lüttge U 1994 Isolation of H+-transport-competent plasma membrane vesicles from corn roots by discontinuous sucrose gradient centrifugation: effect of membrane protectant agents. J. Plant Physiol. 144, 505-512.

    CAS  Google Scholar 

  • Forbush B 1983 Assay of the Na+ K+-ATPase in plasma membrane preparations: Increasing the permeability of membrane vesicles using sodium dodecyl sulfate buffered with bovine serum albumin. Anal. Biochem. 128, 159-163.

    Article  PubMed  CAS  Google Scholar 

  • Giannini JL, Ruiz-Cristin J and Briskin DP 1988 A small scale procedure for the isolation of transport competent vesicles from plants tissues. Anal. Biochem. 174, 561-567.

    Article  PubMed  CAS  Google Scholar 

  • Gerke J 1993 Solubilization of Fe(III) from humic-Fe complexes, humic/Fe-oxide mixtures and from poorly ordered Fe-oxide by organic acids-consequences for P adsorption. Z. Pflanzenernähr. Bodenk. 156, 235-257.

    Google Scholar 

  • Guminski S, Sulej J and Glabiszewski J 1983 Influence of sodium humate on the uptake of some ions by tomato seedlings. Acta Soc. Bot. Pol. 52, 149-164.

    CAS  Google Scholar 

  • Lanfermeijer FC and Prins HBA 1994 Modulation of HC-ATPase activity by fusicoccin in plasma membrane vesicles from oat (Avena sativa L.) roots. Plant Physiol. 104, 1277-1285.

    PubMed  CAS  Google Scholar 

  • Lazof DB, Rufty TW, Jr and Redinbaugh MG 1992 Localization of nitrate absorption and translocation within morphological regions of the corn root. Plant Physiol. 100, 1251-dy1258.

    PubMed  CAS  Google Scholar 

  • Maggioni A, Varanini Z, Nardi S and Pinton R 1987 Action of soil humic matter on plant roots: Stimulation of ion uptake and effects on (Mg2+ + K+) ATPase activity. Sci. Tot. Envir. 62, 355-363.

    Article  CAS  Google Scholar 

  • Mc Clure PR, Kochian LV, Spanswick RM and Shaff IE 1990 Evidence for cotransport of nitrate and protons in maize roots. Effect of nitrate in the membrane potential. Plant Physiol. 93, 281-289.

    CAS  Google Scholar 

  • Nardi S, Concheri G and Dell'Agnola G 1996 Biological activity of humus. In: Humic substances in terrestrial ecosystems. Eds A Piccolo, Elsevier Science BV, 361-406.

    Google Scholar 

  • Pinton R, Cesco S, Santi S and Varanini Z 1997 Soil humic substances stimulate proton release by intact oat seedlings roots. J. Plant Nutr. 20, 857-869.

    Article  CAS  Google Scholar 

  • Pinton R, Cesco S, De Nobili M, Santi S and Varanini Z 1998Water and pyrophosphate-extractable humic substances fractions as a source of iron Fe-deficient cucumber plants. Biol. Fertil. Soil 26, 23-27.

    Article  CAS  Google Scholar 

  • Santi S, Locci G, Pinton R, Cesco S and Varanini Z 1995 Plasma membrane H+-ATPase in maize roots induced for NO -3 uptake. Plant Physiol. 109, 1277-1283.

    PubMed  CAS  Google Scholar 

  • Tsay Y-F, Schroeder JI, Feidmann KA and Crawford NM 1993 A herbicide sensitive gene CHL1 of Arabidopsis encodes a nitrateinducible nitrate transporter. Cell 72, 705-713.

    Article  PubMed  CAS  Google Scholar 

  • Varanini Z and Pinton R 1995 Humic substances and plant nutrition. Progress Botany 56, 97-117.

    CAS  Google Scholar 

  • Varanini Z, Pinton R, De Biasi MG, Astolfi S and Maggioni A 1993 Low molecular weight humic substances stimulate H+-ATPase activity of plasma membrane vesicles isolated from oat (Avena sativa L.) roots. Plant and Soil 153, 61-69.

    Article  CAS  Google Scholar 

  • Vaughan D and Ord BG 1981 Uptake and incorporation of 14Clabelled soil organic matter by roots of Pisum sativum L. J Exp. Bot. 32, 679-687.

    Google Scholar 

  • Wang RC and Crawford NM 1996 Genetic identification of a gene involved in constitutive high-affinity nitrate transport in higher plants. Proc. Natl. Acad. Sci. USA 93, 9297-9301.

    Article  PubMed  CAS  Google Scholar 

Download references

Author information

Authors and Affiliations

Authors

Rights and permissions

Reprints and permissions

About this article

Cite this article

Pinton, R., Cesco, S., Iacolettig, G. et al. Modulation of NO -3 uptake by water-extractable humic substances: involvement of root plasma membrane H+ATPase. Plant and Soil 215, 155–161 (1999). https://doi.org/10.1023/A:1004752531903

Download citation

  • Issue Date:

  • DOI: https://doi.org/10.1023/A:1004752531903

Navigation