First report of High Plains wheat mosaic virus in Ukraine
In 2018, more than 40 wheat (Triticum aestivum) samples showing symptoms of leaf streak were collected in the Ukraine and tested for the presence of wheat streak mosaic virus (Tritimovirus, WSMV). Despite the presence of symptoms and of the mite vector (Aceria tosichella), WSMV was not found, but transmission electron microscopy revealed the presence of an emaravirus. Further studies confirmed the occurrence High Plains wheat mosaic virus (Emaravirus, HPWMoV - formerly EPPO Alert List) in commercial wheat fields in 4 regions of the Ukraine (Dnipropetrovsk, Donetsk, Zaporizhia and Kharkiv), where 56% of symptomatic samples (24 samples out of 43 tested samples) were HPWMoV-positive and approximately 50% were infected by both HPWMoV and WSMV. Subsequently, HPWMoV was also detected in the Vinnytsia region, in 12 samples of maize (Zea mays) plants showing leaf streaking and mosaic. This is the first time that HPWMoV is reported from Ukraine and from the EPPO region.
EPPO note: HPWMoV was first initially found in the USA on wheat and maize in the 1990s (EPPO RS 1999/134), and then also reported from Argentina and Australia. It is transmitted by Aceria tosichella. Seed transmission has been observed at a low rate in sweet maize (EPPO RS 2002/163).
Sources
Snihur H, Pozhylov I, Budzanivska I, Shevchenko O (2020) First report of High Plains wheat mosaic virus on different hosts in Ukraine. Journal of Plant Pathology 102, 545–546. https://doi.org/10.1007/s42161-019-00435-y