HPV is transmitted by the Wheat curl mite (Aceria tosichella). Symptoms are very similar to those for WSMV and include:
â€¢ Leaf mottling (mosaic) and leaf streaking.
â€¢ Light green streaks running parallel to the leaf veins.
These streaks turn yellow and develop into blotches, giving the leaf a green and yellow pattern called a â€˜mosaicâ€™.
â€¢ Tillers on affected plants tend to be less erect than those on uninfected plants. â€¢ Affected plants can die prematurely or fail to grow, becoming stunted relative to healthy plants.
â€¢ Heads on infected plants can be sterile and contain no seed, or can contain small to shrivelled grain. Globally in the field, HPV has been found infecting wheat (Triticum aestivum), maize (Zea mays), green foxtail (Setaria viridis) and yellow foxtail (Setaria glauca). Additional experimentally susceptible species include â€˜Victoryâ€™ oats (Avena sativa), cheat (Bromus secalinus), barley (Hordeum vulgare), and rye (Secale cereale)