Wheat streak mosaic virus has shown up in southern Alberta.
The counties of Lethbridge, Vulcan and Willow Creek have each confirmed the virus in crops and scouting is recommended in all regions south of Red Deer.
As the name implies, wheat streak mosaic virus shows up as yellow streaks on the leaves of cereal crops.
The virus, spread by leaf curl mites, destroys the green chlorophyll necessary for plants to convert sunlight to sugars.
The mites do not have wings so they rely on wind to travel to new feeding grounds.
They can multiply quickly in hot, dry weather such as that recently experienced in southern Alberta and which was in the forecast for the week of July 3.
It has the potential to severely reduce yield. There are no chemical controls.
Wheat streak mosaic virus symptoms can look similar to stripe rust, and as it happens, Alberta Agriculture also reports that stripe rust has been reported in at least seven counties.
They include Cardston, Forty Mile, Lacombe, Lethbridge, Newell, Red Deer and Warner.