Isolates from tubers were more pathogenic and produced earlier wilt onset compared to the water originated isolates, whereas soil and weed isolates were intermediate in this regard. The effect of certain salts, widely used in plant nutrition in different anionic forms along with certain hydroxides currently used as foliar sprays, on the in vitro growth of the pathogen were tried. The tested isolates were more sensitive to NaOH than KOH. The nitrates, KNO₃ (0.6%) caused remarkable increase in in vitro growth of the pathogen, being more pronounced for soil and weed isolates. Similar trend could be observed for Ca (NO3)2, at the same concentration. Differently, chlorides caused deterimental effect on the in vitro growth of the pathogen being more pronounced for FeC12.4H20, CaCl2 and MgC1₂ Sulphates of ammonium, calcium, copper, potassium and zinc (0.6%) caused a pronounced decrease in growth with the exception of magnesium that increased the growth of potato stems and weed isolates. Tomato plants treated with KNO₃ and MgSO₄ resulted in a decrease in the percentage of wilted plants though the favourable effect on the in vitro growth of the pathogen. The same trend was observed for ammonium sulphate. The effect was attributed to an improvement of the plant vigor. Application of KNO3, (NH4)₂ 50₄ along with MgSO₄ at the same concentration, however, increased the percentage of scorched plants. It is worth to note that NaOH, KOH and ZnSO₄ decreased the in vitro growth of the pathogen, and caused a pronounced decrease in the percentage of wilted plants, despite the increase in the percentage of scorched ones.