Excessive soil salinity is an important constraint limiting the distribution of plants in natural habitats, and is an increasingly severe agricultural problem in arid and semi-arid regions. Higher salinity levels caus...Excessive soil salinity is an important constraint limiting the distribution of plants in natural habitats, and is an increasingly severe agricultural problem in arid and semi-arid regions. Higher salinity levels caused significant reduction in growth parameters like leaf area, leaf length and root and shoot dry weight. Salicylic acid (SA), a plant phenolic is now considered as a hormone-like endogenous regulator, and its role in the defence mechanisms against biotic stressors has been well documented. In recent years its role has been widely investigated in abiotic stress (salinity, drought, water deficit and so on). The aim of the present work was to study the effects of salicylic acid on growth and some physiological characters of salt stressed tomato plants. The presence of salicylic acid at low concentration (0.01 mM) in culture medium riched with NaCl 100 mM (6 g·L^-1) improves the tolerance of tomato cv. Golden Sunrise to salinity. This amelioration results in stimulation of growth and development of plants. The applied of SA in saline medium induce: (i) an increase in chlorophyll content; (ii) a better supply of essential elements in plant growth, such as K+; (iii) a decrease in toxic ions such Na+ and CI in aerial organs; and (iv) an additional synthesis of organic solutes and osmoprotectors like proline and proteins. All these results suggest that salicylic acid could be successfully used in alleviating depressive effects of salt on the productivity of the cultivated tomato.展开更多
文摘Excessive soil salinity is an important constraint limiting the distribution of plants in natural habitats, and is an increasingly severe agricultural problem in arid and semi-arid regions. Higher salinity levels caused significant reduction in growth parameters like leaf area, leaf length and root and shoot dry weight. Salicylic acid (SA), a plant phenolic is now considered as a hormone-like endogenous regulator, and its role in the defence mechanisms against biotic stressors has been well documented. In recent years its role has been widely investigated in abiotic stress (salinity, drought, water deficit and so on). The aim of the present work was to study the effects of salicylic acid on growth and some physiological characters of salt stressed tomato plants. The presence of salicylic acid at low concentration (0.01 mM) in culture medium riched with NaCl 100 mM (6 g·L^-1) improves the tolerance of tomato cv. Golden Sunrise to salinity. This amelioration results in stimulation of growth and development of plants. The applied of SA in saline medium induce: (i) an increase in chlorophyll content; (ii) a better supply of essential elements in plant growth, such as K+; (iii) a decrease in toxic ions such Na+ and CI in aerial organs; and (iv) an additional synthesis of organic solutes and osmoprotectors like proline and proteins. All these results suggest that salicylic acid could be successfully used in alleviating depressive effects of salt on the productivity of the cultivated tomato.