The EU Standing Committee on Plants, Animals, Food and Feed (SCoPAFF) has voted not to renew approval for active substance, mancozeb, a fungicide widely used in control of potato late blight and alternaria.
The decision will apply to the UK as it is expected to come into force by the end of December 2020 when the Brexit transition period ends, according to Hazel Doonan, Agricultural Industries Confederation head of crop protection and agronomy sector.
There is expected to be a sales period of six months followed by a use-up period of six months, which means the product should still be able to be used in the 2021 season, she says.
Loss of mancozeb has implications for fungicide resistance management in potato late blight control, says John Sarup of Spud Agronomy. “It is the one [active] with multisite activity therefore it is used as an anti-resistance product. When you look at single site alternatives such as mandipropamid and cyazofamid, the chances of resistance are higher, the more these actives are used.”
Mancozeb is also relatively cheap, says Mr Sarup. “An application of Curzate [cymoxanil + mancozeb] will cost about £10-£12/ha whereas most of the alternatives cost £18-£22/ha.”
Mancozeb is also useful in management of alternaria, says Mr Sarup. “As conditions get warmer and damper, we are seeing more alternaria. Some of the most popular varieties are getting relatively susceptible to it.
“It is another tool in the armoury to control alternaria. Putting on more nitrogen can help minimise the effect of the disease but you still have to kill the crop off without diquat.
“Difenoconazole will have a go but is not great and another active in the pipeline is not available yet.”