Journal article

Publication year: 2021

Pages: 1883-1895

Journal: New Phytologist

Volume number: 230

Issue number: 5

ISSN: 0028-646X

eISSN: 1469-8137

Open access status: Hybrid

DOI Link: https://doi.org/10.1111/nph.17307

Publisher: Wiley

Abstract: 

Understanding P uptake in soil-plant systems requires suitable P tracers. The stable oxygen isotope ratio in phosphate (expressed as delta O-18(P)) is an alternative to radioactive labelling, but the degree to which plants preserve the delta O-18(P) value of the P source is unclear. We hypothesised that the source signal will be preserved in roots rather than shoots.

In soil and hydroponic experiments with spring wheat (Triticum aestivum), we replaced irrigation water by O-18-labelled water for up to 10 d. We extracted plant inorganic phosphates with trichloroacetic acid (TCA), assessed temporal dynamics of delta O-18(TCA-P) values after changing to O-18-labelled water and combined the results with a mathematical model.

Within 1 wk, full equilibration of delta O-18(TCA-P) values with the isotope value of the water in the growth medium occurred in shoots but not in roots. Model results further indicated that root delta O-18(TCA-P) values were affected by back transport of phosphate from shoots to roots, with a greater contribution of source P at higher temperatures when back transport was reduced.

Root delta O-18(TCA-P) partially preserved the source signal, providing an indicator of P uptake sources. This now needs to be tested extensively for different species, soil and climate conditions to enable application in future ecosystem studies.

Harvard Citation style: Bauke, S., Schnepf, A., von Sperber, C., Orlowski, N., Lewandowski, H., Selzner, T., et al. (2021) Tracing uptake and translocation of phosphorus in wheat using oxygen isotopes and mathematical modelling, New Phytologist, 230(5), pp. 1883-1895. https://doi.org/10.1111/nph.17307

APA Citation style: Bauke, S., Schnepf, A., von Sperber, C., Orlowski, N., Lewandowski, H., Selzner, T., Tamburini, F., & Amelung, W. (2021). Tracing uptake and translocation of phosphorus in wheat using oxygen isotopes and mathematical modelling. New Phytologist. 230(5), 1883-1895. https://doi.org/10.1111/nph.17307