Evaluation of in vitro antifungal activity of potassium bicarbonate on Rhizoctonia solani AG 4 HG-I, Sclerotinia sclerotiorum and Trichoderma sp.

摘要

The effect of increased concentrations of potassium bicarbonate (KHCO3) as a possible alternative to synthetic fungicides for controlling?Rhizoctonia solani?AG 4 HG-I?and?Sclerotinia sclerotiorum?was evaluated?in vitro,?in this study.?In addition, the effect of potassium bicarbonate on?Trichoderma?sp.,?a natural antagonist on?R. solani?AG 4 HG-I?and?S. sclerotiorum?was determined. Potassium bicarbonate substantially inhibited (P<0.05) the growth of?the?three fungal strains. Mycelial growth of?R. solani?AG 4 HG-I significantly decreased as the concentration of bicarbonate increased, especially at concentrations greater than 200 mM. Similarly, mycelial growth of both?S. sclerotiorum?and?Trichoderma?sp. dramatically reduced in?increasing?concentrations of KHCO3. Mycelial growth of either fungi was completely inhibited when exposed to 100 mM bicarbonate.?In addition, KHCO3concentrations higher than 10 mM caused significant (P<0.05) reduction of the sclerotium formation of?S. sclerotiorum. Also, sclerotium germination and?de novosclerotium formation were significantly inhibited as the concentrations of KHCO3increased. As a result, it was concluded that potassium bicarbonate was an alternative chemical agent for controlling?R. solani?AG 4 HG-I?and?S. sclerotiorum.Also, KHCO3?was found to have negative effects on?Trichoderma?sp.