Simultaneous application of salicylic acid and calcium improves salt tolerance in two contrasting tomato (Solanum lycopersicum) cultivars

• Published in: South African journal of botany 2014-11, Vol.95, p.32-39
• Main Authors: Manaa, A., Gharbi, E., Mimouni, H., Wasti, S., Aschi-Smiti, S., Lutts, S., Ben Ahmed, H.
• Format: Article
• Language: English
• Subjects: Calcium; Salicylic acid; Salinity; Salt tolerance; Tomato
• ISSN: 0254-6299; 1727-9321
• DOI: 10.1016/j.sajb.2014.07.015

Soil salinity is one of the most important environmental factors responsible for serious agricultural problems. Tomato salt tolerance may be improved by genetic selection and by the use of adapted physiological tools. The aim of this study was to investigate the impact of exogenous application of salicylic acid (SA 0.01mM) and calcium sulphate (CaSO4 5mM), singly or in combination, on plant growth, photosynthetic pigments, nutritional behaviour and some metabolic parameters (total chlorophyll, carotenoids, soluble sugars, proline and lipid peroxidation) of two tomato cultivars (cv. Super Marmande and cv. Red River) exposed to salt stress (100mM NaCl). Application of 100mM NaCl reduced plant growth, total chlorophyll and carotenoid contents. Salt stress also induced an accumulation of Na+, a decrease in K+ and Ca2+ concentration and root sugar level, an increase in malondialdehyde (MDA) and proline concentration. Deleterious impact of salinity was related to modification in ion content rather than modification in the plant water status. Exogenous application of SA or Ca alone improved plant behaviour in the presence of NaCl. Nevertheless, the best results in terms of growth, photosynthetic pigment concentrations and mineral nutrition (limitation of Na+ accumulation and maintenance of K+ and Ca2+ content) were obtained in response to the combined SA+Ca treatment. Although the involved physiological parameters varied depending on the considered cultivar, our results suggest that Ca2+ and SA may interact to reduce the stress experienced by the plant in the presence of NaCl. •Deleterious impact of salinity was related to modification in ion content.•SA and Ca impaired the salt effects on plant growth, especially in Super Marmande.•(SA+Ca) alleviated the salt effect on chlorophyll pigment contents.•SA and/or Ca induced a significant decrease in leaf Na+ concentration.•SA and/or Ca alleviated adverse effect of salinity on root sugar level.