Stop BYDV in wheat with aphid control
Healthy fields bring higher yields but may also serve as beacons for hungry insects. Although the worst U.S. drought since 1956 caused pastures and crops to deteriorate, it also left fewer host plants and fall crop stubble for insects to feed on.
Aphids that feed on infected host plants and crop stubble, can carry the devastating barley yellow dwarf virus (BYDV) to wheat planted this fall. With a few more weeks of winter wheat planting left, there is still potential for fall aphid pressure to creep up on growers. To reduce risk, it’s important for growers to be proactive and protect their crops from the start, enabling them to grow more wheat and achieve higher profits.
Although the 2012 drought may have decreased the potential for fall aphid pressure, it only takes one aphid to transmit BYDV to a field. There are multiple species of aphids, but only certain species transmit BYDV. Most common of the BYDV-transmitting aphids include the bird cherry-oat aphid, corn leaf aphid, English grain aphid and Greenbug.
Aphids contract BYDV by feeding on infected host plants, and then BYDV is spread as infected aphids feed on healthy plants. This virus can cause underdeveloped root systems, plant stunting, winterkill, decreased tillering, delayed maturity, nutritional disorders and reduced grain quality and yield.
Researchers have identified that the fall population of aphids has the greatest potential to vector BYDV and leads to the most dramatic decrease of yield in the spring. If growers are not proactive in ensuring their crops are protected this season, this tiny insect can have a devastating impact on yield by vectoring BYDV.
Eliminate the Green Bridge and scout fields
First and foremost, researchers and agronomists recommend delaying fall planting, eliminating the green bridge and diligently scouting fields.
With the drought this year, delaying planting until the later part of the planting window may allow for more moisture, and it can also help growers actively prevent aphid infestations. Later fall planting dates are recommended to give aphids less time to transmit the virus before cold temperatures set in.
Agronomists also suggest eliminating the green bridge by controlling green residue in the field. This residue will act as a “bridge,” connecting infected aphids to the new crops and allowing for the spread of BYDV.
“We recommend that growers destroy any green residue with a burndown application of a herbicide at least two weeks before planting begins to eradicate the green bridge and break pest cycles,” said Les Glasgow, herbicide technical asset lead, Syngenta, who noted the company has choices to accomplish the task.