Experts have outlined the best way to use the last remaining granular nematicide against potato cyst nematode (PCN) – the crop’s most damaging soil pest.
The government’s refusal to re-authorise oxamyl leaves Nemathorin as the only remaining granular control method. Growers switching to the product should follow guidelines for best results, says Syngenta technical manager Michael Tait.
The same equipment can be used for the application of granules – but must be fitted with Nemathorin specific rotors or cartridges and calibrated to accurately deliver the 30kg/ha application rate for PCN.
“Nemathorin cannot be applied in-furrow,” says Mr Tait. Instead, granules should be incorporated evenly to a depth of 15cm in the soil profile during seedbed preparation, immediately prior to planting.
Incorporation to a consistent depth across all soil types and conditions is important, because Nemathorin is relatively immobile in the soil profile – which helps achieve good levels of control.
“If field conditions change, check the incorporation depth and adjust accordingly,” says Mr Tait.
Growers and agronomists must not desiccate or harvest crops for at least 17 weeks (119 days) after application. A harvest interval calculator on the Syngenta website means growers can check the earliest potential desiccation or lifting date.
When ccurately incorporated into the soil, Nemathorin has consistently shown higher yields through greater PCN control compared to fluopyram liquid nematicide or a combination of liquid and reduced rate granular product.
UK crop trials on a commercial Suffolk farm showed a 10% higher yield from Nemathorin – some 56 t/ha – compared to fluopyram applied in furrow.
Other trials have confirmed higher yields and improved marketable tuber size
Effective control of PCN with an integrated approach to crop management is advocated wherever populations are identified by soil sampling. Managing even low egg counts can
help to protect yields of the growing crop, says Mr Tait.
Nemathorin minimises the multiplication and build-up of pest numbers, reducing the damage caused by wireworm, along with the free-living nematodes responsible for the transmission of spraing.
“Accurate application of Nemathorin following the protocols of the Nematicide Stewardship
Programme will help assure yields are protected in the growing crop and sustainable management of PCN in the long-term.”