Neoscytalidium Dimidiatum as a Postharvest Pathogen Affecting Solanaceous Vegetables

Abstract

Neoscytalidium dimidiatum, a member of the Botryosphaeriaceae family, is an emerging global plant pathogen. Although recently reported on various hosts in T & uuml;rkiye, its impact on commercially available vegetables remained undocumented. This study provides the first report of N. dimidiatum causing postharvest decay in the eggplant (Solanum melongena L.), pepper (Capsicum annuum), potato (Solanum tuberosum), and tomato (Solanum lycopersicum) obtained from local Turkish markets in 2023. The pathogen was identified through morphological characterisation and molecular analysis targeting the internal transcribed spacer (ITS) region, translation elongation factor 1-alpha (tef1), and beta-tubulin (tub2) gene sequences. The pathogenicity of N. dimidiatum was confirmed through Koch's postulates at 28 degrees C, and its temperature-dependent effects were assessed on solanaceous vegetables. Disease progression, measured by the area under the disease progress curve (AUDPC), was strongly influenced by temperature. No disease was observed at 12 degrees C. At 18 degrees C, limited disease development occurred in the eggplant and potato. AUDPC values increased significantly at 25 degrees C, generally peaking at 30 degrees C, with some hosts showing similar levels of disease severity at 35 degrees C. These findings highlight the critical role of postharvest temperature control, particularly rapid cooling and cold storage, in minimising losses caused by N. dimidiatum. This is the first report of N. dimidiatum as a postharvest pathogen affecting the eggplant, pepper, tomato fruits, and potato tubers, and the first record of this pathogen on the eggplant and pepper globally, expanding its known host range and reinforcing its significance as an emerging threat to global agriculture.