Bill Cissel, Extension Agent – Integrated Pest Management; bcissel@udel.edu
Congratulations to Joe Streett for correctly identifying the disease as wheat spindle streak mosaic virus and for being selected to be entered into the end of season raffle for $100 not once but five times. Everyone else who guessed correctly will also have their name entered into the raffle. Click on the Guess the Pest logo to participate in this week’s Guess the Pest challenge!
Guess the Pest Week #7 Answer: Wheat Spindle Streak Mosaic Virus (WSSMV)
By Nancy Gregory, Extension Plant Diagnostician
Wheat spindle streak mosaic virus (WSSMV) and wheat soilborne mosaic are two similar viruses found in wheat in the spring when there has been cooler weather. Affected areas may appear stunted in low lying, wetter areas of the field. The viruses persist in primitive fungus-like organisms (not pathogens of wheat) in the soil, even during rotation out of wheat for a year or two. Symptoms of WSSM include yellow mottle or flecking and the lesions are spindle or dash like (elongated) in shape. Virus testing is expensive and not reliable for these viruses. Plants grow out of the symptoms when temperatures rise, and there is usually little to no yield loss. There are no other controls for these viruses which for which wheat is the only known host.