SEARCH

SEARCH BY CITATION

Keywords:

  • Carotenoids;
  • chlorophyll fluorescence;
  • halophyte;
  • relative growth rate;
  • stomatal conductance;
  • water use efficiency

The following article from Plant Biology, “Growth, ion homeostasis, photosynthesis and photosystem II efficiency of an obligate halophyte, Salicornia brachiata, under increasing salinity (p)” by A. K. Parida, C. M. Hari Kishore & B. Jha, published online on 1 April 2010 (DOI: 10.1111/j.1438-8677.2010.00336.x) in Wiley InterScience (http://www.interscience.wiley.com), has been retracted by agreement between the authors, the journal Editor-in-Chief, Heinz Rennenberg and Blackwell Publishing Ltd.

The retraction has been agreed due to concern about overlap with the article “Relationship between the photosynthetic activity and the performance of Cakile maritima after long-term salt treatment” by Ahmed Debez, Hans-Werner Koyro, Claude Grignon, Chedly Abdelly, Bernhard Huchzermeyer published in Physiologia Plantarum (2008) vol. 133, 373-385.

Abstract

We examined the effects of salinity (0–600 mm NaCl) on growth, photosynthesis, photosystem II (PSII) efficiency, ion relations and photosynthetic pigment content in Salicornia brachiata. Relative growth rate (RGR) was optimum at 200 mm NaCl and was inhibited at higher salt concentrations; however, relative water content (RWC) of shoots was unaffected by salinity. Accumulation of Na+ increased with the increase in salinity of shoots, with a concomitant decrease of K+ and Ca2+. Despite the large amount of Na+ accumulated in shoots of salt-treated plants, neither leaf dehydration nor symptoms of severe shoot injury were noticed, indicating no osmotic or toxic effects of salt because of effective compartmentation of salt in vacuoles. Chlorophyll and carotenoid concentrations increased at optimal salinity and decreased at extreme salinities. Although reduced in the presence of high salt concentrations, chlorophyll and carotenoid content remained relatively high. Net photosynthesis (A), stomatal conductance (gs), intercellular CO2 concentration (Ci), maximum quantum efficiency of PSII (Fv/Fm) and quantum yield (ΦPSII) were stimulated at low salinity (200 mm NaCl). Higher salinity adversely affected gas exchange and PSII functional characteristics, resulting in a reduction of A per unit leaf area. This was associated with increased non-photochemical quenching (NPQ). Higher salt levels impaired photosynthetic capacity of S. brachiata mainly via stomatal limitation, as gs was severely reduced. The absence of pigment degradation, reduction of water loss and concomitant PSII protection from photodamage through thermal dissipation of excess excitation energy significantly increased the survival capacity of S. brachiata grown at high salinity.