POTATOES TREATED with chlorpropham (CIPC) now have to comply with a new Maximum Residue Limit (MRL), growers and store managers have been advised.

The limit of 10 parts per million has been introduced as part of the Annex 1 listing under the EU review of pesticides and means potatoes will now be subject to testing for CIPC residues, said the British Potato Council’s Adrian Briddon.

“I don’t think it will pose too many problems for British growers, but they should be aware that potatoes will now be subject to testing.”

CIPC residue testing will be included in quarterly surveys carried out by the Pesticide Residue Committee, he added. Brussels has not yet formally signed off the new limit, but growers should treat it as law from now on, he said.

In order to help store managers ensure crops remain within the MRL, the BPC has issued the following advice:

  • Minimise the number of crops/stores treated by segregating crops by dormancy
  • Early applications are most effective. If sprouts are evident at the first treatment, a second may be required quickly, but check label for re-treatment intervals
  • Do not apply CIPC if the crop is wet, or damage has not cured
  • Store the crop at the lowest possible constant temperature to limit sprout growth
  • Even distribution of CIPC can be helped by recirculation of fog at low air speed. But recirculation is not recommended on all products and growers should discuss options with their fogging contractor
  • Do not let CIPC leak out of stores

Further storage advice is available at www.potato.org.uk/sbeu or on freephone 08000 282111.