Syngenta UK: Integrated controls for PCN management

With just one remaining approved granular nematicide for PCN control in maincrop potatoes, getting the best from soil pest IPM programmes are more important than ever for long term management, advocates Syngenta Technical Manager, Michael Tait.

That includes extending rotational breaks as far as practicable and the effective control of volunteers and host weeds between crops, he urged. Speaking at the Potato Science Live events, he highlighted experience with G. rostochiensis has shown good results can be achieved with growing resistant varieties, but more suitable cultivars are now required to tackle G. pallida.

“Using Nemathorin in combination with cultural measures gives the best chance to both protect yields and minimise the impact of PCN multiplication,” he advised.“Managing PCN populations even at low egg counts will be essential for sustainable future production."

Mr Tait reminded growers that Nemathorin has a minimal interval of at least 17 weeks from application to desiccation or harvest. “Whilst that harvest interval does preclude its use on short season crops, it is in place because of the persistence of the product that makes it so effective for PCN control in maincrop potatoes.”

Watch how to get the best from Nemathorin application this season

He reported a series of trials over many seasons and soil types that has shown it is the best option to optimise yield protection in longer season crops.

Nematicide stewardship

With the need for ongoing proactive nematicide product stewardship, Mr Tait advocates growers and agronomists should positively check and record there have been no adverse effects on wildlife following application.

Whilst there have been no recorded incidences over all the years with Nemathorin use, it is important to collect and store the evidence of no effects, should its future be challenged, he recommended.    

Wireworm challenge

Wireworm has been a recurring issue for many potato growers over recent seasons, possibly as a result of changing climatic conditions for pests, along the withdrawal of Mocap (ethoprophos) and neonicotinoid seed treatments that also had an effect through the rotation.

That has seen a surge in interest in Nemathorin as growers seek to reduce the effects of wireworm damage to tubers.

Furthermore, Syngenta Insecticides Technical Manager, Dr Max Newbert, outlined proposals for a granular formulation of lambda-cyhalothrin that trials have shown could offer better results.

The product is currently in development across a number of European countries and in submission for a UK registration.

Research will also investigate optimising in-furrow application techniques to achieve an even distribution of bait points surrounding tubers. The product is specifically targeted at wireworm in potatoes and maize.