Evaluation of inhibitory effect some bicarbonate carbonate salts against Neoscytalidium dimiatum

Abstract

Neoscytalidium dimidiatum, a member of the Botryosphaeriaceae family, has emerged as a significant pathogen causing canker and blight diseases in various fruit trees, field crops, park and forest trees, and other hosts. Neoscytalidium dimidiatum is the only recognized species within the genus, with the other two previously recognized species, N. novaehollandiae and N. orchidacearum. There is no suggested chemical control method against Neoscytalidium. In this study, we evaluated the inhibitory effect of some salts on the mycelial growth, germ tube elongation and conidial germination of the N. dimidiatum isolate phylogenetically clustered with the isolates previously recognized as N. novaehollandiae. The antifungal effects of the salts were determined at 0.125, 0.25, 0.5, 1.0 and 2.0% (w/v) concentrations of salts in vitro conditions. Statistically, differences were observed between the inhibitory effects of six salts on the parameters at P ≤ 0.05. The 0.25% and higher concentrations of the ammonium bicarbonate and ammonium carbonate salts completely inhibited mycelial growth, germ tube elongation and conidial germination. Potassium and sodium bicarbonate salts in the highest concentration (2.0%) were able to decrease the mycelial growth, germ tube elongation and conidial germination with the rates of 95.58%-95.58%, 95.05%-95.76% and 77.44%-82.91%, respectively. In addition, potassium and sodium carbonate were able to completely inhibit investigated factors of the pathogen at 2.0% and 1.0% concentrations, respectively. The minimum inhibition concentration values of the ammonium bicarbonate, potassium carbonate and sodium carbonate varied between 0.25% and 2.0%. The minimum fungicidal concentration values of the ammonium carbonate and bicarbonate also ranged between 0.25% and 1.0%. As a result, this study showed that salts of carbonate and bicarbonate could be recommended to manage diseases caused by N. dimidiatum.