Effect of NaCl and Polyethylene glycol on the in vitro growth of two potato fungal pathogens Rhizoctonia solani and Fusarium solani

Soil salinization and drought can adversely affect microorganisms inhabiting this compartment and modulate their interaction with plants. In this study we evaluated the tolerance of two soil born fungal strains belonging to the species Rhizoctonia solani and Fusarium solani to grow at different concentrations of salt (0 to 1000 mM of NaCl ) and polyethylene glycol 6000 (0 – 37 % of PEG6000) in PDA and LB media. The results showed that R. solani showed better tolerance to NaCl concentration in LB in comparison to PDA medium, whereas the opposite behavior was noticed for F. solani. In addition, F. solani showed better tolerance to both NaCl and PEG6000 concentrations in comparison to R. solani. These results may help to understand and predict the impact of soil and water salinization on the development soil born fungal pathogens on cultivated plants.