What is Barley Yellow Dwarf Virus?
This is a disease that affects grains in most places in the U.S. where they are grown. Because of how widespread it is and how it affects yield, it is considered to be one of the most important grain diseases farmers face. Barley yellow dwarf disease is caused by a virus that is spread by aphids. Just 30 minutes of feeding on an infected plant and one of these tiny insects is capable of transferring the virus to the next plant on which it feeds. The name barley yellow dwarf is used because it is descriptive of the symptoms the disease causes in barley. Yellow dwarf virus on oat crops causes slightly different symptoms, but the name has stuck and is called barley yellow dwarf no matter which grain it infects.
Symptoms of Oat Barley Yellow Dwarf Virus
Barley yellow dwarf virus in oats may cause some minor early symptoms that look like nutrient deficiencies, herbicide injury, or root rot, so it can be easy to overlook initially. Later, the disease will cause yellow discoloration at the leaf tips, which in oats will then turn red or purple. These spots turn bright yellow in barley and yellow or red in wheat. Discolored leaf tips may curl in and the leaves generally become stiff. Timing of infection can cause different effects. Oats with barley yellow dwarf virus that begins when the plants are young will be stunted and produce less. When the disease sets in during the fall, plants may die over the winter, even without showing any symptoms. When older plants develop the disease, they may only show signs on new growth.
Managing Barley Yellow Dwarf Virus in Oats
To prevent major yield losses in your oats, it is important to take steps to prevent or manage this viral disease. There are resistant varieties of oats, which is a good place to start. Only plant your oats during the time of year recommended. Early spring sowing, for instance, can increase the risk of aphid exposure. Remove any volunteer grains from your fields, as these can harbor the disease. Insecticides for aphids may be of limited usefulness because the effect doesn’t last very long. Early spring, when plants are young and most vulnerable, is the best time to try chemical control. You can also try adding ladybugs, a natural aphid predator, to your garden and promoting an environment that is conducive to their presence.
