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In order to study the diverse effects of seed priming with 24-epibrassinolide (EBL) (0, 0.1, 1 mg/l) to increase tolerance of tomato plants (Lycopersicon esculentum Mill.) to salinity (0, 70 and 140 mM NaCl), the experiments were conducted as factorial based on completely randomized design at greenhouse condition. Results showed that salt stress significantly decreased the growth of tomato plants. However, priming with EBL (1 mg/l) significantly decreased the negative effects of NaCl (particularly at 140 mM). At this case, EBL increased the fresh and dry weights (<2 folds), total chlorophyll (+72%), carotenoids (+ 2 folds), free proline (+3 folds), electrolyte leakage (-18.6%), Na⁺/K⁺ in the roots (-57.5%) and shoots (-62%) compared to salinity control. Generally, it could be concluded that priming with epibrassinolide resulted in enhanced salt tolerance in tomato plants via increment in free proline, photosynthetic pigments and decrease in electrolyte leakage and Na⁺/K⁺ ratio in the tissues.
 

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The present study aimed to investigate the effect of some bio-elicitors and silver nitrate on the content of secondary metabolites in calli derived from leaf explants of silybum marianum. In this research, the best callus was achieved on MS medium containing KIN, thus this medium was chosen for further experiment. In the second experiment, leaf explants were cultured in a selected hormone-regulated medium. After 8 weeks of callus growth, bio elicitors including yeast Yarrowia lipolytica, fungus Aspergillus niger, and bacterium Pseudomonas putida in combination with silver nitrate as a non-living elicitor were added to the leaf-derived calli. Ten days after treatment, the phenolic compound content, antioxidant capacity, silymarin content, and PAL enzyme activity in the calli were measured. The results indicate that the simultaneous application of Yarrowia yeast and silver nitrate led to an improvement in the content of phenolic derivatives, silymarin, and PAL enzyme activity, and this was significant compared to other elicitors both with silver nitrate and without it. The researchers of this experiment suggest that the combined use of bio-elicitors especially Yarrowia lipolytica yeast, and silver nitrateinduces higher synthesis of medicinal metabolites in calli derived from leaf explants.