Occurrence of virus infections on cereal crops and their identifications in the Trakya region of Turkey

WOS: 000232704300001Some virus infections exhibiting yellowing, dwarfing, streak mosaic, necrosis of tillers, mottle and reduction in yield of cereal crops have prevailed since 1999 in the Trakya region of Turkey. Infection rates were 32.33 % in winter wheat (Triticum aestivum L.), 26.52 % in barley (Hordeum vulgare L.), 8.32 % in oat (Avena sativa L.), 61.63 % in bird seed (Phalaris canariensis L.) and 8 % in triticale in 2001. Rates of virus infections in 2002 however were 17.27 % in winter wheat, 15.22 % in barley and 16.5 % in oats. The main purpose of this study was to identify the viruses by employing biological, serological and molecular tests. For this purpose 90 cereal leaf samples in 2001 and 106 plant samples in 2002 were collected from the infected fields located in the Edirne, Kuklareli and Tekirdag provinces. Samples were inoculated mechanically to eight indicator plant series. Thirty-seven inoculated samples caused virus-like symptoms on at least one indicator test plant. By employing 11 polyclonal antisera, DAS-ELISA tests were implemented. Serological test results however revealed that 63 out of 90 samples contained barley yellow dwarf virus-PAV (BYDV-PAV), nine out of 90 samples containing wheat streak mosaic virus (WSMV) and only two out of 90 samples had oat necrotic mottle virus (ONMV) in 2001 and 14 out of 106 cereal plant samples revealed the presence of BYDV-PAV in 2002. RT-PCR tests also confirmed the presence of BYDV-PAV in the area by having primers 534 kb amplification product. Presence of Rhopalosiphum padi L. with a high degree of infestation implies that BYDV-PAV is responsible for the major virus infection in the area. This is the first report for the presence of ONMV and BYDV-PAV identified by DAS-ELISA and molecular RT-PCR tests in Turkey