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Strawberry is considered as a salinity sensitive species and is adversely affected in response to the salt stress in terms of growth and yield. Pot experiments were conducted to determine the effect of exogenous salicylic acid (SA) application on physiology, growth, chlorophyll and mineral content of strawberry grown under salt stress and greenhouse conditions. Strawberry plants were treated with SA at different concentrations (0.0, 0.25, 0.50 and 1.00 mM). Salinity treatments were established by adding 0 and 35 mM of NaCl to a base complete nutrient solution. Salt stress negatively affected the growth, chlorophyll content and mineral uptake of strawberry plants. However, plants treated with SA often had greater shoot fresh weight, shoot dry weight, root fresh weight and root dry weight as well as higher chlorophyll content under salt stress. The greatest values were obtained with 1.00 mM SA treatment in both saline and non-saline conditions. Leaf water relative content (LWRC) was reduced in response to salt stress while electrolyte leakage was raised. SA treatments induced increases in LWRC and decreases in electrolyte leakage compared to the control under salt stress. With respect to the nutrient content, SA treatments increased almost contents of all nutrients in leaves and roots of strawberry plants under salt stress. The greatest values were often obtained by the 1.00 mM SA treatment. These findings suggest that the SA treatments can ameliorate the negative effect of salinity on the growth of strawberries. Key words: salinity, growth, mineral content MELHORA DO EFEITO DE ESTRESSE SALINO EM MORANGO POR ADIÇÃO DE ÁCIDO SALICÍLICORESUMO: O morango é considerado uma espécie sensível à salinidade e é negativamente afetado por estresse salino, em termos de crescimento e produção. Por meio de experimentos em vaso foi determinado o efeito de ácido salicílico exógeno (SA) na fisiologia, crescimento, conteúdos de clorofila e de minerais, em morangueiros cultivados em estufa sob estresse salino. As concentrações de SA foram 0.0, 0.25, 0.50 e 1.00 mM. O estresse salino foi verificado pela adição de 0 e 35 mM de NaCl à uma solução nutritiva completa. O estresse salino afetou negativamente o crescimento, o conteúdo de clorofila e a absorção dos nutrientes minerais. Entretanto, plantas tratadas com SA muitas vezes apresentam maiores pesos frescos e secos, além de maior concentração de clorofila, sob condições de estresse salino. O conteúdo relativo de água das folhas (LWRC) foi reduzido em resposta ao estresse salino, enquanto o extravasamento de eletrólitos aumentou. Os tratamentos com SA induziram a aumentos em LWRC e diminuições no extravassamento de eletrólitos, em comparação com os controles sob estresse salino. Com respeito aos conteúdos de nutrientes, houve aumento para quase todos os nutrientes com adição de SA nas folhas e raízes sob estresse salino. Os maiores valores forma geralmente obtidos para 1.00 mM SA. Estes resultados sugerem que os tratamentos com SA podem atenuar os efeitos negativos da salin...

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Plant root and shoot dry weight, leaf relative water content (LRWC) and chlorophyll content were reduced by 30%, 21%, 15%, 34%, respectively, at 40mM NaCl as compared to non-salt stress conditions. However, membrane permeability (MP) of plant increased (85.0%) with increasing salinity. Foliar nutrient application (FNA) alleviated deleterious effects of salinity stress on growth and this effect was statistically significant. The highest alleviation effect of FNA at 40mM salinity stress was observed in the case of 10mM foliar KNO 3 and Ca(NO 3 ) 2 application, resulting in increase in plant root dry weight (50%), shoot dry weight (50%), LRWC (8.2%) and MP decrease (27.4%) at 40mM NaCl. Phosphorus, Fe and Zn contents in shoots and roots of plants also increased with FNA treatments, but they were still much lower than those of non-salt stress treatment. Sulphur, P, Fe and Zn contents of shoots reached similar values as in non-salt stress treatment when KNO 3 was applied, whereas Fe, Mn, Zn, and Cu contents of roots reached the values of non-salt stress treatment when Ca(NO 3 ) 2 was applied.

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