Molecular identification of burn spot disease syndrome agent Fusarium avenaceum in Turkish crayfish Pontastacus leptodactylus populations

In this study, we aimed to isolate and identify the causative agent of burn spot disease syndrome from crayfish populations within Turkish water bodies. Crayfish Pontastacus leptodactylus samples were captured from Bayramşah Reservoir, Karaidemir Reservoir and Keban Reservoir (Turkey). Fungi samples were taken from symptomatic crayfish and cultured in potato dextrose agar, and DNAs were extracted. Species-specific PCR primers (FAF1 and FAR) were used in order to amplify the internal transcribed spacer (ITS) region of fungal DNA. Sequences obtained from the amplified regions were analyzed using GenBank and identified. As a result, a molecular diagnosis of the fungi samples was made, and the pathogen was identified as Fusarium avenaceum. In addition, a challenge test with healthy crayfish was conducted to evaluate the pathogenicity of the fungi. F. avenaceum was reisolated from experimentally infested individuals, and thusly we confirmed the disease. It was concluded that F. avenaceum causes burn spot disease syndrome in P. leptodactylus.