First report of dill blight caused by Itersonilia perplexans in Turkey
KeywordsDill Itersonilia perplexans Dill blight Turkey
During January 2018, when temperatures average around 5.8–14.8 °C, blight symptoms were observed on leaves, petioles and stems of dill (Anethum graveolens) plants grown in a greenhouse of 2 decares located in Antalya province of Turkey. The disease affected less than 2% of the total area. The symptoms appeared on all aerial parts of plant as small, greyish necrotic lesions. Seriously affected parts became completely dry and died over time. Symptomatic tissues were cut into small pieces, plated on potato dextrose agar (PDA), and incubated at 25 °C for 10 days. A fungus was consistently isolated from diseased tissues, whose colonies were flat, circular, whitish to cream-colored. The fungus was identified as Itersonilia perplexans based on morphology and DNA sequence comparisons. Mycelium was straight, hyaline with clamp connections at the septa. Sporogenous cells (n = 20) were thin-walled, pyriform, ovoid to subglobose, 14.64 ± 3.36 × 7.28 ± 1.15 μm in size. Ballistospores (n = 20) were lemon-shaped, hyaline, broadly-lunate, 18.04 ± 2.52 × 13.80 ± 1.03 μm in size. The ribosomal internal transcribed spacer (ITS) region was amplified with ITS1 and ITS4 primers, sequenced and deposited in GenBank under the accession No. MH348181. BLAST analysis of sequence showed 99% identity with the neotype of I. perplexans, CBS 363.85, NR_077117 (Boekhout et al. 1991). To confirm pathogenicity, disease-free plants were inoculated with ballistospore suspension according to the method described by Aldaoud et al. (2009). One week later, typical blight symptoms were observed on inoculated leaves and stems but not on control plants. The pathogen was reisolated from inoculated leaves, fulfilling Koch’s postulates. Similar symptoms caused by I. perplexans on dill were reported in Bulgaria and Australia (Aldaoud et al. 2009; Rodeva et al. 2009). To our knowledge, this is the first report of dill blight caused by I. perplexans in Turkey.
- Rodeva R, Gabler J, Stoyanova Z (2009) First evidence of Itersonilia perplexans on dill (Anethum graveolens) in Bulgaria. Sodininkystėir daržininkystė 28:193–198Google Scholar