Investigation of the efficacy of licensed some fungicides against Neoscytalidium dimidiatum in organic agriculture

Malatya is Turkey's most important apricot production center and it provides 46.2% of the total apricot production with approximately 8 million apricot trees. Malatya, known as capital of apricot, meets 80% of dried apricot export. Neoscytalidium dimidiatum (Penz.) Crous & Slippers causes sudden shoot drying and die back in apricot orchards in Malatya province. In this study, it was aimed to determine the possibilities of chemical and biological control in organic agriculture by in vitro studies of the pathogenic fungus Neoscytalidium dimidiatum, which does not have a regulated chemical control. The effect of fungal biocontrol agents Trichoderma viride and Trichoderma harzianum and bacterial biocontrol agents Bacillus amyloliquefaciens, Bacillus subtilis and Pseudomonas fluorescens as well as copper oxide, copper oxycloride, copper hydroxide and Bordoux slurry and tea tree oil which are allowed to be used in ecological agriculture were investigated against the mycelial growth of N. dimidiatum Kale 4C isolate. The percentage of radial growth inhibition of the T. viride preparation among the biological preparations was determined as 81.71% in this study. Among the chemical pesticides, Gulleci slurry at a 1% dose was found to be prevent the pathogen at the rate of 86.85% of. As a result, it was demonstrated that Trichoderma species and Gulleci mixture showed high activity against N. dimidiatum (Penz.) Crous & Slippers for the first time. These results show that these biological actives and Gülleci slurry have the potential to be used against the causal agent. KEY WORDS: Neoscytalidium, Apricot, Organic agriculture, Biological control, Trichoderma