Display options
Share it on

Funct Plant Biol. 2014 Apr;41(4):391-400. doi: 10.1071/FP13241.

Photosynthetic performance and biochemical adjustments in two co-occurring Mediterranean evergreens, Quercus ilex and Arbutus unedo, differing in salt-exclusion ability.

Functional plant biology : FPB

Lina Fusaro, Simone Mereu, Cecilia Brunetti, Martina Di Ferdinando, Francesco Ferrini, Fausto Manes, Elisabetta Salvatori, Riccardo Marzuoli, Giacomo Gerosa, Massimiliano Tattini

Affiliations

  1. Department of Environmental Biology, Sapienza University of Rome, P.le Aldo Moro, 5 - 00185, Rome, Italy.
  2. Department of Science for Nature and Environmental Resources (DipNET), University of Sassari, Piazza Università 21 - 07100, Sassari, Italy.
  3. Department of Agri-Food Production and Environmental Sciences, University of Florence, Viale delle Idee 30, 50019, Sesto Fiorentino, Florence, Italy.
  4. Department of Mathematic and Physic, Catholic University of Brescia, Via Musei 41 - 25121 Brescia, Italy.
  5. The National Research Council of Italy, Department of Biology, Agriculture and Food Sciences, Institute for Plant Protection, Via Madonna del Piano 10, I-50 019, Sesto Fiorentino, Florence, Italy.

PMID: 32480999 DOI: 10.1071/FP13241

Abstract

The responses to mild root zone salinity stress were investigated in two co-occurring Mediterranean woody evergreens, Quercus ilex L. and Arbutus unedo L., which differ in morpho-anatomical traits and strategies to cope with water deficit. The aim was to explore their strategies to allocate potentially toxic ions at organism level, and the consequential physiological and biochemical adjustments. Water and ionic relations, gas exchange and PSII performance, the concentration of photosynthetic pigments, and the activity of antioxidant defences, were measured. Q. ilex displayed a greater capacity to exclude Na+ and Cl- from the leaf than A. unedo, in part as a consequence of greater reductions in transpiration rates. Salt-induced reductions in CO2 assimilation resulted in Q. ilex suffering from excess of light to a greater extent than A. unedo. Consistently, in Q. ilex effective mechanisms of nonphotochemical quenching, also sustained by the lutein epoxide-lutein cycle, operated in response to salinity stress. Q. ilex also displayed a superior capacity to detoxify reactive oxygen species (ROS) than A. unedo. Our data suggest that the ability to exclude salt from actively growing shoot organs depends on the metabolic cost of sustaining leaf construction, i.e. species-specific leaf life-span, and the relative strategies to cope with salt-induced water stress. We discuss how contrasting abilities to restrict the entry and transport of salt in sensitive organs relates with species-specific salt tolerance.

Publication Types