First report of Stagonospora nodorum blotch caused by Parastagonospora nodorum on emmer wheat (Triticum dicoccum Schrank) in Turkey
KeywordsEmmer wheat Stagonospora nodorum rDNA-ITS region Turkey
Tetraploid emmer (Triticum dicoccum Schrank) wheat is a transitional form of the modern durum wheat and cultivated under marginal areas of some European countries including Turkey (Gurcan et al. 2017). In April 2017, a survey was conducted in advanced emmer wheat line growing areas at the experimental fields of Akdeniz University, Antalya, Turkey. A leaf spot disease with approximately 60% incidence was observed in the field. Pale brown lesions with small dark pycnidia were observed on leaves of the plants. Small pieces of fungus were obtained from the lesions with the aid of a scalpel under binocular microscope. Conidial suspensions (1 × 109 conidia/mL) were put on Petri dishes containing potato dextrose agar (PDA) for one week at 20–24 °C under fluorescent lights for 12 h photoperiod to induce sporulation. Fungal hyphal fragments were placed on cellophane paper autoclaved at 120 °C for 1 h and put on the PDA medium to obtain single-conidial cultures. Microscopic examination with at least 50 conidia showed that the conidia were hyaline, straight to slightly curved, cylindrical, 1 to 3-septate, 19 to 29 μm × 2.6 to 3.0 μm. Based on morphological characteristics of the isolate, the pathogen was identified as Parastagonospora nodorum (Bissett 1982). To verify these morphological data, DNA was extracted from fungus scraped from cellophane paper on Petri dishes by CTAB method. The rDNA internal transcribed spacer (ITS) region including 5.8S rDNA was amplified with primers of ITS1 and ITS4 and sequenced. The sequence was deposited in GenBank with the accession number MG994969. The sequence of our isolate was compared to sequences of other Parastogonospora sp. obtained by Quaedvlieg et al. (2013). A phylogenetic analysis under the Neighbor Joining criterion illustrated that it grouped in a clade with type strain of P. nodorum isolate CBS 259.49 (KF251185) and almost maximum bootstrap value (99%). To sum up, P. nodorum has been reported from many countries in Europe, the Americas and Australia. This is the first report of P. nodorum on emmer wheat in Turkey.
The work was supported by The Scientific and Technological Research Council of Turkey (TUBITAK) with the project number 214O401.
- Bissett J (1982) Stagonospora nodorum. Fungi Canadenses No. 240. National Mycological Herbarium, Biosystematics Research Institute Agriculture Canada, OttawaGoogle Scholar