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Use of over-yeared treated wheat seed in 2020

With poor planting conditions in the autumn now continuing into the new year, a number of questions are being raised about the suitability of treated wheat seed from autumn 2019 for use in autumn 2020.

There are a number of important points to consider:

  • Many growers are considering all options with regard to spring sowing, including sowing of winter wheat in January, February and possibly beyond. Care should be taken to ensure the correct variety is used in these situations, as all varieties have different latest safe sowing dates in order to ensure vernalization. Refer to the AHDB recommended list and speak to your seed merchant and/or seed breeder for more details on varieties.
  • If treated seed is to be over-yeared then absolute attention must be paid to storage conditions which should be cool, dry and dark with particular care taken to protect from vermin and livestock.

By far the safest way to dispose of treated seed is to plant it, but the following must be considered:

  • All seed that has been over-yeared must be carefully sampled and then germination tested as close to the intended planting date as possible. This may result in an adjustment to the required seed rate based on the results.
  • Whilst Certis cannot guarantee the germination and efficacy of treated seed that has been over-yeared there are factors that would lead growers to store with confidence. For example the fact that in general, seed in 2019 had a good thousand grain weight (TGW) and was of low moisture. If your seed was home saved then consider the condition it was in before treating, it should have been below 16% moisture.
  • Always refer to the product label for the seed treatment you have on your seed.

For further information regarding Certis seed treatments, call the Technical Hotline on 0845 373 0305 and ask for Seed Treatment Manager, Tim Eaton.