Although these actual protection costs may be broadly similar, independent consultant and former Velcourt director Keith Norman says there are several other benefits to controlling a disease which can potentially give crop losses in the UK of £136m a year.
He also points out that the lack of neonicotinoid seed treatment will increase selection pressure on pyrethroids, where there is already well-known resistance in the aphid populations.
Wolverine’s BYDV resistance originated from a goat grass, a distant relative of wheat, and the relevant resistance gene, Bdv2, was transferred to wheat in a breeding programme that dates back 20 years.
The disease is spread by grain aphids and bird cherry aphids, and warm weather encourages aphid activity and hence virus spread.
Other wheats with the resistance gene are being developed in Australia, New Zealand and the United States, but this in the first variety developed for Europe, while experience from Australia suggests the resistance will be durable.
RAGT cereal pathologist Ruth Bryant says there has been no evidence of resistance from aphids, and the levels of BYDV seen in the variety Wolverine have been from trace levels down to zero.
“We have a good level of resistance, not complete, but it is looking good in the field and the lab,” said Dr Bryant. “The fact the resistance is not complete bodes well for durability as this will exert less pressure on the virus to adapt.”
The breeder also points out that the variety gives good yields and competes with top-yielding varieties such as Gravity and Skyscraper, even when there is no BYDV to be seen.
Tom Dummett, the group’s cereal and oilseed rape product manager, said the variety offered growers an alternative to chemical control for the first time.
He said the variety was capable of delivering exceptional yields even in the absence of BYDV and was backed by a strong agronomic package, so growers would not be penalised for choosing it in low-disease years.