The interactive effects of salinity, calcium and potassium on physiomorphological traits of sorghum (Sorghum biclolor L.) were studied in a green-house experiment. Treatments included 4 levels of NaCl (0, 80, 160, and 240 mM NaCl), 2 levels of CaCl2 (0 and 20 mM), and 2 levels of KCl (0 and 20 mM). Salinity substantially reduced the plant growth as reflected by a decrease in the plant height, shoot and root weight, and percent of mortality and delay in the reproductive stage, but the relative water content as well as CO2 assimilation rate and transpiration rate were negatively affected only at severe salinity. Root/shoot weight and leaf blade/total plant weight ratios were increased under saline conditions, which led sorghum to tolerate in the presence of salinity. Application of supplemental calcium resulted in partially restoring the adverse effects of high salinity on plant growth, whilst application of additional potassium had a negative interaction on plant growth characteristics. Combined application of Ca2+ and K+ also resulted into an ameliorative effect on sorghum growth and morphological traits under salinity stress.

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