Beet aphid warning
Beet aphid warning
SUGAR beet growers should check crops not treated with Gaucho (imidacloprid) for aphid activity, says IACR-Brooms Barn.
One of the first aphids trapped this year was found to be carrying virus, showing crops are at risk of infection if aphid numbers are allowed to build up, warns researcher Mike May.
Control with Aphox (pirimicarb) or Aztec (triazamate) if there are aphid predators present, or a pyrethroid if not, is recommended at a threshold of four aphids/plant. "At that level we have to assume there is virus about," he says.
Crops surrounded by Gaucho-treated fields will be partly sheltered from invasion, but aphids were found on untreated trials at Brooms Barn last week.
"The plants were only at the two-leaf stage. Virus infection now could result in significant yield loss: 30-40%," he warns. *