Cabbage (Brassica oleracea) is a cruciferous vegetable consumed worldwide and is used in traditional medicine. In October 2018, during a survey to determine the presence of viral diseases in cabbage, virus-like symptoms were observed on cabbage plants (cv. Srpski melez) growing in the Futog locality, South Bačka District, the main cabbage-producing area in Serbia.
"Disease incidence was estimated at 40%. Plants exhibiting symptoms of stunting and purpling of the leaves were collected and tested by commercial DAS-ELISA diagnostic kits (Loewe Biochemica, Germany) against turnip yellows virus (TuYV), turnip mosaic virus, and cauliflower mosaic virus. Out of 20 samples tested, 15 were positive for TuYV and negative for the other tested viruses", the scientists at University of Belgrade explain.
The aphid transmissibility of the selected serologically positive sample (364Cb) was tested using Myzus persicae as the vector. Nymphs of aphids were allowed to feed for an acquisition access period of 24 h and thereafter transferred onto three plants of each Physalis floridana and Sinapis alba for a 4-day inoculation access period, with a 16-h photoperiod at 22°C. All inoculated P. floridana plants manifested a very mild interveinal chlorosis, whereas all inoculated S. alba plants reacted with a mild reddening of leaf margins and yellowing 5 weeks postinoculation. In the same manner, the virus was successfully transmitted to cabbage plants (cv. Futoški), which reacted with a mild yellowing symptom 6 wpi. DAS-ELISA was used to confirm the presence of TuYV in all inoculated plants.
"BLAST analysis revealed that the Serbian isolates 345Cb and 364Cb shared the highest nucleotide identity of 97.83% with TuYV-SA isolate (MH427303) of TuYV from Australia and 98.5% with Raphanus sativus isolate (Raph M) of TuYV from Germany (Y16876). In additional, the Serbian TuYV isolates 345Cb and 364Cb are grouped in the cluster with the known TuYV isolates - the scientists underline - The virus has been recorded on Brassica napus in Serbia in 2015, but to our knowledge, this is the first report of TuYV on B. oleracea in the country. Vectors of TuYV are widespread in Serbia. With both B. oleracea and B. napus serving as a reservoir of TuYV in Serbia, production of these and other important brassica hosts of the virus is threatened".
Source: Dragana Milošević, Maja Ignjatov, Slobodan Vlajić, Zorica Nikolić, Jelica Gvozdanović Varga, Ivana Stanković, Branka Krstić, 'First Report of Turnip Yellows Virus on Cabbage in Serbia', 2020, Plant Disease, Vol. 104 (3).