Abstract
Excessive salinity in irrigation decreases crop's growth in arid regions such as Saudi Arabia. The aim of this research was to study the combined effects of salinity and temperature on germination, plant growth, F
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, gas exchange, chlorophyll and proline content in two Sorghum bicolor cultivars, Hindi and Jaizani. The treatments contained 3 temperatures (20°C, 30°C, 40°C) and 4 NaCl concentrations (0, 50, 100, 200 mM). The results presented that as NaCl increased, germination, growth, gas exchange and F
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of the two cultivars declined, with great effects at 40°C than at the other temperatures. Proline was higher in the Hindi and Jaizani cultivars at 20°C and 30°C under the different salinity conditions. On the other hand, the chlorophyll content was increased at 20°C under increased salinity in both cultivars. The interactions between salinity and temperature significantly affected most measurements of the two cultivars; however, Hindi cultivar showed more tolerance toward stress.