Aphid Report – Autumn Update 31st October 2014

We apologise for an error in aphid report of 27th October 2014. Updated report below.

The aphid monitoring programme conducted by Rothamsted Research has confirmed the presence of grain aphids (Sitobion avenae) that carry the kdr mutation making them resistant to pyrethroid insecticides. Grain aphid and bird-cherry aphid (Rhopalosiphum padi) are the main vectors for the transmission of barley yellow dwarf virus (BYDV) in winter wheat and barley.

Pyrethroid insecticides, such as cypermethrin, have been invaluable in the control of aphid species as they have been cost-effective. However the over-reliance of pyrethroid insecticides has resulted in resistance.

Independent trials conducted in autumn 2012 and reported at Crop Protection Northern Britain 2014 (*Dewar et al., 2014) demonstrated that Dursban® WG was the most consistent insecticide treatment when applied against resistant or susceptible grain aphid. Dursban WG achieved faster aphid control than cypermethrin, vital when combating virus transmission.

aphid controlAction

Monitor crops and where aphid species are present and pyrethroid resistance is implicated, consider an application of Dursban WG or Equity®. Trial results have shown that applications of Dursban WG applied via LERAP 3* nozzles did not reduce aphid control.

If treatment is justified use Equity at 1.0 L/ha applied in 200 to 1000 litres of water/ha.

If using Dursban WG the recommended rate is 0/6 Kg/ha applied in 200 to 1000 litres of water/ha.

An interval of 14 days must be observed between applications of Dursban WG and UNITE® or Broadway® Star, regardless of weather conditions. For approved formulations of iodosulfuron-methyl-sodium and mesosulfuron-methyl leave a longer interval of 4 weeks for crop safety.

Use low drift nozzles and extend buffer zones to preserve Dursban WG and Equity use.

For conventional boom sprayer:

  • Use LERAP – low drift – three star nozzles
  • AND adopt a 20 metre no-spray buffer zone (1 metre for dry water bodies)

Say No to Drift

 

 

*A M Dewar, A J G Dewar, L A Haydock, S P Foster and M S Williamson. Alternative insecticides to control cereal aphids, Sitobion avenae, that are resistant to pyrethroids. Crop Protection in Northern Britain 2014, pp 136-136

Important label update for users of ASTROKerb

Dow AgroSciences is pleased to inform growers and advisors that CRD has granted an approval for ASTROKerb® to allow the straw from oilseed rape crops treated with ASTROKerb to be burnt for heat or electricity production. The following updated statement will now appear on the label : “DO NOT remove oilseed rape straw from the field unless it is to be used for burning for heat or electricity production.”

Agronomy Update – 21 October 2014

In this Edition

Getting the best ryegrass control in winter wheat
I have no blackgrass so why should I bother with a “residual”?
What can I use to control vol. beans in wheat?

This Edition’s FAQs:
Does Kerb Flo 500 control ryegrass?
Is there still “no –known” blackgrass resistance to Kerb Flo 500?
Can I use Galera this autumn?

Dates for the diary

New Anglia regional manager for Dow AgroSciences

Peter Waite_lowresExperienced crop protection manager Peter Waite has joined Dow AgroSciences as Regional Business Manager for the South Anglia region, covering Suffolk, Essex, Hertfordshire and parts of Buckinghamshire, bringing a wealth of local and sector knowledge to the company’s sales team.

Biologist boost for Dow AgroSciences customer service team

Nicola Perry_lowresBiologist Dr Nicola Perry has joined the Dow AgroSciences Customer Focus Team as Technical Services Specialist, focussing on sales support including marketing, communication, public relations and technical support plans.