As agricultural producers look ahead to the remainder of the growing season, plant specialists from the University of Nebraska-Lincoln (UNL) Extension are providing insight into emerging wheat diseases. A survey conducted at the beginning of June in Cheyenne County wheat fields identified wheat streak mosaic and barley yellow dwarf.
Barley yellow dwarf is typically caused by a virus of the same name, and it primarily impacts cereal crops and grasses. Wheat leaves may appear pale yellow, but depending on local temperatures, a red-purple discoloration might also be present. The disease is often transmitted by aphids.
Wheat streak mosaic is caused by a virus of the same name, and it typically first appears in volunteer wheat. Infected plants may sport streaked leaves in a green-yellow color, and the yellowing may become more intense as temperatures increase in the region. Wheat curl mites are usually responsible for transmitting the disease.
There are various strategies agricultural producers can use to control these diseases, according to plant pathologists. For barley yellow dwarf, in particular, it’s best to delay fall seeding until aphid populations decline. This reduces the risk of disease and can be effective when combined with measures such as planting more resistant varieties and deploying insecticides. Controlling grassy weeds and volunteer cereals near production fields can also help.
To control wheat streak mosaic, it’s best to focus on controlling volunteer wheat, which should be dead at least two weeks before planting. Some wheat varieties also have high levels of resistance.
More information on wheat diseases and management tips can be found by visiting the UNL Cropwatch website at cropwatch.unl.edu.