Zero-calorie sugar delivery to roots


Resistance to moving sugars from foliage to roots is high in trees, suggesting that the transport mechanism found in herbs might not work in trees. Now with new measurements of phloem structure and leaf turgor pressure, it has been shown that the Münch pressure-flow hypothesis can also explain sugar transport in tall trees.

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Fig. 1: Vascular transport in tall trees.


  1. 1.

    Münch, E. Die Stoffbewegungen in der Pflanze (Gustav Fischer, 1930).

  2. 2.

    Thompson, M. V. Trends Plant Sci. 11, 26–32 (2006).

    CAS  Article  PubMed  Google Scholar 

  3. 3.

    De Schepper, V., De Swaef, T., Bauweraerts, I. & Steppe, K. J. Exp. Bot. 64, 4839–4850 (2013).

    Article  PubMed  Google Scholar 

  4. 4.

    Thompson, M. V. & Holbrook, N. M. Plant Cell Environ. 26, 1561–1577 (2003).

    Article  Google Scholar 

  5. 5.

    Knoblauch, J., Mullendore, D. L., Jensen, K. H. & Knoblauch, M. Plant. Physiol. 166, 1271–1279 (2014).

    Article  PubMed  PubMed Central  Google Scholar 

  6. 6.

    Mullendore, D. L., Windt, C. W., Van As, H. & Knoblauch, M. Plant Cell 22, 579–593 (2010).

    CAS  Article  PubMed  PubMed Central  Google Scholar 

  7. 7.

    Savage, J. A. et al. Maintenance of carbohydrate transport in tall trees. Nat. Plants (2017).

  8. 8.

    Mencuccini, M. & Holtta, T. New Phytol. 185, 189–203 (2010).

    CAS  Article  PubMed  Google Scholar 

  9. 9.

    Jensen, K. H., Liesche, J., Bohr, T. & Schulz, A. Plant Cell Environ. 35, 1065–1076 (2012).

    CAS  Article  PubMed  Google Scholar 

  10. 10.

    Jyske, T. & Hölttä, T. New Phytol. 205, 102–115 (2015).

    CAS  Article  PubMed  Google Scholar 

  11. 11.

    Hölttä, T., Mencuccini, M. & Nikinmaa, E. J. Theor. Biol. 259, 325–337 (2009).

    Article  PubMed  Google Scholar 

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Correspondence to Michael G. Ryan.

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Ryan, M.G., Robert, E.M.R. Zero-calorie sugar delivery to roots. Nature Plants 3, 922–923 (2017).

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