How do we control Barley Yellow Dwarf Mosaic in a barley field seeded in fall...
How do we control Barley Yellow Dwarf Mosaic in a barley field seeded in fall in Preble county?
Preble County Ohio
Barley is the most sensitive cereal grain crop to barley yellow dwarf virus, so special care must be used. How close will this field be to volunteer cereal crops currently growing? The closer the volunteer cereal field the greater the risk. Here are the things to consider to reduce the problem, but you can't eliminated it completely:
- A few BYD resistant varieties are available, but these are resistant to only a few of the BYD virus species or isolates within a species. It is therefore necessary to know which species of the virus are predominant and the species to which each variety is resistant in order to make the correct variety selection for each area. Consult with your seed dealer for varieties with resistance to BYD.
- Plant winter wheat after the Hessian fly-free date and barley as late as practical to avoid early fall infections. Fresh green leaves of early autumn plantings attract aphids and may lead to severe infestations. Later planting helps winter cereals escape aphid population buildup in the fall. Plant spring oats as early as possible. Vigorously growing plants are more tolerant of BYD than are weaker ones. Large populations of aphids usually do not appear in Ohio until later in the spring.
- Proper fertilization is necessary for good crop growth. Plants with nutritional stress are more susceptible and yield less.
- Control volunteer wheat, barley and oats. Volunteer plants can be a problem in double-cropping systems. These plants can serve as important reservoirs of the virus for the next crop.
- Contact insecticides act directly on aphids, but have short residual effect and may not last long enough to protect the field from a subsequent influx of virus-carrying aphids. Some systemic insecticides have been used successfully in some states where severe BYD epidemics occur. In these areas, aphids typically fly in from virus infected grain crops. Systemic insecticides require that the aphids feed on the plant and feeding may be long enough to inoculate the plant with virus, however it reduces the chances of spreading the disease by killing the insect before they can inoculate other plants.