Physiological Disorders of the Nicotianamine-auxothroph Tomato Mutant chloronerva at Different Levels of Iron Nutrition II. Iron Deficiency Response and Heavy Metal Metabolism

https://doi.org/10.1016/S0015-3796(89)80080-0Get rights and content

Summary

The tomato mutant chloronerva exhibits typical symptoms of iron deficiency. Iron deficiencyinduced proton secretion occurs up to 10 µM FeEDTA in the nutrient medium (wild-type only at iron supply lower than 1 µM). Thickened root tips and root hair zones are formed up to 20 µM Fe (wild-type root hairs up to 5 µM). The ferric reductase activity of the rhizodermis remains higher than in the wildtype up to 100 µM Fe supply.

In the concentration range of 5 to 10 µM Fe supply the mutant accumulates the 2- to 3-fold amount of iron in the shoot compared with the wild-type. The increased uptake of certain heavy metals (e. g. Cu, Mn, Zn) by the wild-type under iron deficiency is extended to a higher iron supply range in the mutant.

All these deviations from the wild-type behaviour are overcome by the supply with nicotianamine (NA) to the leaves. The role of NA as an intracellular transporter for Fe(II) in the regulation of iron metabolism and iron deficiency response mechanisms is discussed.

References (47)

  • G. Scholz et al.

    The effect of nicotianamine on the uptake of Mn2+

    Zn2+, Cu2+, Rb+ and PO3-4 by the tomato mutant chloronerva., Biochem. Physiol. Pflanzen

    (1987)
  • G. Scholz et al.

    Nicotianamine increases the uptake of FeEDDHA by plants of micromolar iron concentration.

    Biochem. Physiol. Pflanzen

    (1985)
  • P.C. Sijmons et al.

    Development of Fe3+ reduction activity and H+ extrusion during growth of iron-deficient bean plants in a rhizostat.

    Biochem. Physiol. Pflanzen

    (1986)
  • R. Becker et al.

    The influence of nicotianamine on adventitious root formation in hypocotyls of the tomato mutant chloronerva (Lycopersicon esculentum Mill.).

    Physiol. Plant.

    (1989)
  • I. Beneš et al.

    Metal complex formation by nicotianamine

    a possible phytosiderophore., Experientia

    (1983)
  • H.F. Bienfait

    Regulated redox processess at the plasmalemma of plant root cells and their function in iron uptake.

    J. Bioenerg. Biomembr.

    (1985)
  • H.F. Bienfait

    Biochemical basis of iron efficiency reactions in plants

  • H.F. Bienfait et al.

    Characterization of ferric reducing activity in roots of Fe-deficient Phaseolus vulgaris.

    Physiol. Plant.

    (1983)
  • H.F. Bienfait et al.

    Free space iron pools in roots.

    Plant Physiol.

    (1985)
  • J.C. Brown

    Mechanism of iron uptake by plants.

    Plant, Cell and Environm.

    (1978)
  • R.L. Chaney et al.

    Obligatory reduction of ferric chelates in iron uptake by soybeans.

    Plant Physiol.

    (1972)
  • S. Fushiya et al.

    Synthesis of avenic acid A and 2’-deoxymugineic acid, amino acids possessing an iron chelating activity

    Chemistry Letters

    (1981)
  • L. Jacobson et al.

    The relation between iron and chlorophyll contents in chlorotic sunflower leaves.

    Plant Physiol.

    (1956)
  • Cited by (0)

    Part 35 in the series “The ‘normalizing factor’ for the tomato mutant chloronerva”. For part 34 see U.W. Stephan and Ž. Procházka (1989).

    *

    Author's address: Dr. Udo W. Stephan, Zentralinstitut für Genetik and Kulturpflanzenforschung der Akademie der Wissenschaften der DDR, Corrensstraße 3, Gatersleben, DDR - 4325.

    View full text