Days are getting shorter, and the variable temperatures of this summer mean that pest control activity from beneficial insects is declining in protected crops, which may call for intervention for an efficient clean-up as cropping seasons come to an end, reports crop protection firm Certis.

According to the company, their pest control treatment Oberon (spiromesifen) is safe to be used alongside beneficial insects such as Encarsia to control whitefly.

The chemical is ‘ideal’ to use alongside biological controls on an end of season crop, when the temperatures drop to below the optimum level for beneficials of 18-20 degrees. “It provides that extra level of control, without interfering with the biological predator and is effective against strains of whitefly resistant to other treatments. In addition, when used for whitefly control there is also a sde benefit of spider mite control,” said Certis technical officer Alan Horgan.

Certis reports that Oberon has both contact and translaminar activity on the pest, preventing the manufacture of fatty acids needed for protein production, stopping young whitefly growing and causing adult whitefly to lay infertile eggs. Two applications may be applied, with the follow-up spray seven to ten days after the initial treatment, and with a three-day harvest interval, applications can be managed around harvesting.

Horgan recommended a clean-up of the glasshouse at the end of the cropping period, using a disinfectant on the structure and the equipment to delay the onset of pests and diseases. “This will remove algae and kill any pathogens whether they be fungal, viral or bacterial, ensuring a clean start for the following season,” he said.