Authors : Deniz Çaplık, Gülten Nisan Ozan, Harun Bayraktar, Mustafa Küsek
DOI : 10.1007/s42161-024-01591-6
Volume : 106
Issue : 2
Year : 2024
Page No : 769-769
Maize or corn (Zea mays L.) is one of the world’s most important crop plants (Revilla et al. 2022). In August 2022, symptoms of stem and leaf blight, wilting and root rot were observed in a maize field with a disease incidence of 3% in Şeyhçoban district of Şanlıurfa, Turkey (37°08’47.0"N 38°51’20.0"E). To isolate the pathogen, stem tissues of symptomatic 10 plants were sampled, surface-sterilized in 1% NaOCl solution for 2 min, plated on potato dextrose agar (PDA) and incubated at 25 °C for 7 days in dark. A total of 20 isolates with similar morphological characteristics were recovered from all samples. Colonies on PDA were initially white with powdery aerial mycelia but gradually darkened. Arthroconidia were dark-brown, thick-walled, 0–1 septate, rod-shaped, 5.63 to 10.45 × 2.7 to 4.4 μm (n = 30). Pycnidiospores produced on pine needles on 1.2% water agar were hyaline, ellipsoidal, 0–1 septate and 3.7 to 5.6 × 11.2 to 13.2 μm (n = 30). The fungus was identified as Neoscytalidium dimidiatum based on these morphological characteristics (Crous et al. 2006). The identity of a representative isolate was also confirmed by sequencing of the internal transcribed spacer (ITS) and the translation elongation factor 1-α gene (EF1-α) gene regions. The resultant sequences were deposited in the GenBank database (Accession Nos. OR770105 for ITS and OR784450 for EF1-α) and showed 100% identity with the ITS (Accession No. KF531820) and EF1-α (Accession No. KF531798) sequences of the strain CBS 499.66 of N. dimidiatum (Penz.) Crous & Slippers. Phylogenetic tree based on Neighbor-Joining method of ITS and EF1-α sequences confirmed the identification of N. dimidiatum. To evaluate pathogenicity, stems of five 45-days-old maize plants were wounded with a sterilized needle and inoculated with mycelial discs from one-week-old culture. Sterile PDA plugs were used as controls. Inoculated and control plants were transferred to a growth chamber at 25 °C. After 30 days, blight symptoms were observed on inoculated maize plants. No symptoms were observed on controls. N. dimidiatum was reisolated from inoculated lesions and morphologically identified. To our knowledge, this is the first report of N. dimidiatum associated with blight symptom of maize in Turkey.