Effect of Different Chemical Inducers on Mycelial Growth of Neoscytalidium dimidiatum

Neoscytalidium dimidiatum has become one of the most aggressive fungal pathogen that cause economical damage to plants with changing climatic conditions. Pathogen causes disease symptoms including dieback, canker, blight, root rot, leaf spot, and fruit rot at a wide range of plant species and significant yield losses and damages. Few studies have been conducted on the efficiency of different chemical fungicides against the pathogen, but no effective control method has been found. Also, comprehensive studies on different control methods were needed due to the disadvantages in the use of chemical fungicides. The aim of the study was to evaluate the effects of chitosan (1, 1.5, 2 mg/ml), metyl jasmonate (MeJA; 0.01, 0.1, 1 mM) and acibenzolar-S-methyl (BTH; 0.01, 0.1, 1 mM) on mycelial growth of N. dimidiatum. The results showed statistically significant differences among the inhibition rates of chemical inducers against N. dimidiatum, but also among different doses of chemical inducers as compared to control. Chitosan at 2 mg/ml concentration was the most effective with the inhibition rate of 45.2%, followed by 1.5 mg/ml and 1 mg/ml doses of chitosan that inhibited mycelial growth at the rates of 44.6 and 37.9%, respectively. BTH was the second most effective treatment after chitosan with the inhibition rate of 18.9% at 1 mM dose, while MeJA was sufficiently ineffective in inhibiting the mycelium growth of N. dimidiatum at the concentrations tested. The results indicated that chitosan could be an alternative to fungicides due to its high level of effectiveness and non-toxicity.