Increasing mercury (Hg) accumulation in soil deteriorates cultivated soils, decreases growth and yield of plants, and contaminates the food chain. Therefore, the main objective of this study was to evaluate the effects of three Hg levels (0, 75 and 150 mg. l-1) in a saline soil with and without Pseudomonas putida (PTCC 1696) on the growth parameters of the turnip plant. Pots were filled with 3 kg of saline soil (EC: 8.65 dS.m-1) and inoculated with Pseudomonas putida. Turnip (Brassica rapa L.) seeds were sown in all the pots. After 10 days, the soils were treated with either 0, 75 or 150 mg. l-1 of Hg until the final Hg concentrations in soil were either 0, 75 or 150 mg/kg. The pots were arranged in a completely randomized design in a greenhouse. After 60 days of planting, soluble sugars, chlorophyll a (Chla), chlorophyll b (Chlb) and catalase enzymes (CAT) in leaf samples were determined while fresh and dry weights of roots and shoots and Hg concentrations in turnip were determined 70 days after sowing. The results showed that inoculated soils produced plants with higher soluble sugars, Chla, Chlb;(are Chla and Chlb the same as Chla and Chlb) fresh and dry weights of roots and shoots were also significantly higher perhaps due to improved nutrients uptake from the stressed soil. At the same time, CAT and total Hg concentrations in the roots and shoots were reduced probably due to efficient nutrient uptake even when Hg was present. The addition of Pseudomonas putida to saline soil contaminated with Hg alleviated salinity and Hg toxicity stress of the turnip plants. In conclusion, Hg polluted saline soil inoculated with Pseudomonas putida (PTCC 1696) was efficient in increasing the quality and quantity of turnip plants and improving soil health compared to the non-inoculated soil.

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