Wheat streak mosaic virus detected in winter wheat in Lithuania

Wheat streak mosaic virus (WSMV) causing viral diseases in graminaceous plants worldwide has been isolated in Lithuania from natural infected winter wheat (Triticum aestivum L.) plants. The diseased wheat plants with pronounced symptoms (chlorotic mottling, streaks of leaves and stunting) were found in various localities of Vilnius and Kaunas regions. Virus isolates were investigated by serology, electron microscopy (EM) and reverse transcription-polymerase chain reaction (RT-PCR) methods. The identification of the virus was based on the results of symptomology on host-plants, positive DAS-ELISA (double-antibody sandwich enzyme-linked immunosorbent assay) test, particle morphology (presence of flexuous, filamentous virus particles similar to 15 nm in diameter and 700 nm in length) and a specific amplification fragment size (750 bp) of virus RNA (ribonucleic acid) in RT-PCR. Isolate (WSMV-1313) of WSMV from wheat plants was characterized by a coat protein gene sequence analysis. Comparison with other WSMV isolates from the GenBank database showed that the Lithuanian WSMV isolate shares the highest sequence similarity to WSMV isolates from Russia (98.3%) and Italy (98.1%). This is the first report of wheat as a natural host for WSMV in Lithuania.