First report of tomato brown rugose fruit virus in Türkiye

Since January 2019, greenhouse tomato plants growing in Demre, near Antalya, in the Mediterranean region of Turkey, have been observed to have leaves with chlorotic mosaic, mottling, roughness, and occasional narrowing. Necrotic spots were observed on the peduncle, calyxes, and petioles, and the fruit was rough with chlorotic and necrotic patches. These symptoms resemble those caused by several different tomato viruses.

Twenty-seven samples of diseased tomatoes were taken from two greenhouses (of which approximately 20% of the total area of ​​0.7 ha was diseased) and analyzed by RT-PCR for the presence of Cucumber mosaic virus , Tobacco mosaic virus ( TMV), Tomato mosaic virus (ToMV), and Tomato spotted wilt virus . Since the results of these assays were all negative, a set of generic primers (F-3666/R-4718) was used to detect tomato-infecting tobamoviruses by RT-PCR (Luria et al ., 2017), and this led to the generation of a 1052 bp amplicon that was directly sequenced (GenBank accession number MK888980). BLAST analysis of the amplicon sequence revealed 98.0-98.9% sequence identity to Tomato Brown Rugose Fruit Virus (ToBRFV) isolates from Germany, Israel, and Jordan (KT383474, KT383474, KX619418, and MK273189).

Ten plants of a commercial tomato variety, Bandita F1 (Seminis, Turkey), which carries the Tm-2 ^resistance gene , were mechanically inoculated with extracts from diseased tomato leaves. All plants developed systemic mosaic symptoms and tested positive for ToBRFV using the tobamovirus-specific primers described above. The amplicons were sequenced to confirm their identity as ToBRFV. Inoculated plants tested negative using RT-PCR with primers specific for ToMV and TMV (Kumar et al ., 2011). Winter-grown tomato production is important to Turkey's economy, and Antalya is the main off-season production center. If ToBRFV is shown to be causing significant production problems in Antalya, then control measures should be implemented. This is the first report of ToBRFV infecting tomatoes in Turkey.

Source: BSPP