First report of Globisporangium heterothallicum causing root and crown rot of pepper in Turkey

S. Derviş, G. Özer, Ş. Türkölmez, O. Çiftçi
2020 New Disease Reports  
Turkey is the world's third-largest producer of pepper (Capsicum annuum), annually cultivating over 90,000 ha and producing over half a million tonnes of fruit. In 2019, wilting and death of c. 20% of plants were observed in pepper fields in Şanlıurfa province, Turkey (Fig. 1) . Severe root and crown rot symptoms with discoloration were observed on affected plants, and necrotic lesions expanded rapidly into the stems which killed the plant (Fig. 2) . To isolate the putative pathogen, small
more » ... athogen, small pieces of symptomatic root (5-10 mm) were surface sterilised in 70% ethanol for 30 seconds then transferred onto grated apple cornmeal agar amended with antimicrobial agents. Twelve oomycete isolates with abundant hyphal swellings were purified by subbing single hypha onto new plates and incubating at 20°C for one week in the dark. Sporangia were formed, terminal or intercalary, (sub-)globose or lemon-shaped, and grew up to 20 µm in diameter (Fig. 3) . A sexual stage was not observed. The internal transcribed spacer (ITS) and the large subunit (LSU) of the nuclear rDNA and mitochondrial cytochrome oxidase II gene (cox II) of two representative isolates were sequenced using primer pairs ITS4/ITS6, NL1
doi:10.5197/j.2044-0588.2020.041.036 fatcat:el7obqhw7jf6rfgixcts67jque