Sulphur deprivation limits Fe-deficiency responses in tomato plants
Author(s)
Zuchi, Sabrina
Cesco, Stefano
Varanini, Zeno
Pinton, Roberto
Astolfi, Stefania
Date Issued
2009
Type
Article
Abstract
Aim of this work was to clarify the role of S supply in the development of the response to Fe depletion in Strategy I plants. In S-sufficient plants, Fe-deficiency caused an increase in the Fe(III)-chelate reductase activity, 59Fe uptake rate and ethylene production at root level. This response was associated with increased expression of LeFRO1 (Fe(III)-chelate reductase) and LeIRT1 (Fe2+ transporter) genes. Instead, when S-deficient plants were transferred to a Fe-free solution, no induction of Fe(III)-chelate reductase activity and ethylene production was observed. The same held true for LeFRO1 gene expression, while the increase in 59Fe2+ uptake rate and LeIRT1 gene over-expression were limited. Sulphur deficiency caused a decrease in total sulphur and thiol content; a concomitant increase in 35SO42- uptake rate was observed, this behaviour being particularly evident in Fe-deficient plants. Sulphur deficiency also virtually abolished expression of the nicotianamine synthase gene (LeNAS), independently of the Fe growth conditions. Sulphur deficiency alone also caused a decrease in Fe content of tomato leaves and an increase in root ethylene production; however these events were not associated with either increased Fe(III)-chelate reductase activity, higher rates of 59Fe uptake, or over-expression of either LeFRO1 or LeIRT1 genes. Results show that S-deficiency could limit the capacity of tomato plants to cope with Fe-shortage by preventing the induction of the Fe(III)-chelate reductase and limiting the activity and expression of the Fe2+ transporter. Furthermore, the results support the idea that ethylene alone cannot trigger specific Fe-deficiency physiological responses in a Strategy I plant, such as tomato.
Additional information
L'articolo é disponibile sul sito dell'editore: http://www.springerlink.com
Citation
Zuchi, S. et al. 2009. Sulphur deprivation limits Fe-deficiency responses in tomato plants. "Planta" 1(230): 85-94.
File(s)![Thumbnail Image]()
Name
Planta_2009.pdf
Size
646.77 KB
Format
Adobe PDF
Checksum (MD5)
295adb46a22552232c1d072a63162c48
Sponsor(s)
Research was supported by grants from Italian
M.I.U.R.-COFIN 2006.
M.I.U.R.-COFIN 2006.