Potato growers: Plan blight control to reduce resistance risk

You are currently viewing Potato growers: Plan blight control to reduce resistance risk

Total control failure in potato blight management product, mandipropamid (Revus) was confirmed in Europe in December (2022), meaning British growers must plan an anti-resistance strategy.

While the resistant blight genotype (EU43) is yet to be identified on British shores, UK farmers must act to protect potato crops, says Geoff Hailstone, potato lead at UPL UK. “Blight strains that start in Europe inevitably make their way over here. So, farmers need to plan their blight control programmes carefully.”

Aarhus University, Denmark and leading agri-chemical companies confirmed the resistance in a joint study. “It is essential that all growers, regardless of varietal choice and fungicide programme, plan an anti-resistance strategy against potato blight,” says a spokesperson for the University.

While a concern, blight resistance to fungicidal products is not a novel situation for UK growers, and lessons of the past have been learnt, says Mr Hailstone. “As a result of previous fungicide resistance issues, the UK has a robust blight monitoring program and a responsible approach to control. British producers still have plenty of options to choose from, but solo product applications must be avoided.”

Instead, growers should consult their agronomists about product mixing, he adds. “The advice should be to mix blight control products with at least one active ingredient from another group. And with each application, mixes need to be alternated.”

Growers should be mindful that all carboxylic acid amide (CAA) group fungicides, of which mandipropamid is one, could also pose a resistance threat. “There is a cross-resistance risk between CAA products,” says Mr Hailstone. “CAA group products contain dimethomorph, benthiovalicarb, or mandipropamid. We need to monitor these fungicides, as there may be additional losses from this product group.

“A prudent approach would be to look at mixing single-site products like mandipropamid with a multi-site product like Manzate 75 WG (mancozeb) or using Proxanil (propamocarb + cymoxanil) which contain actives from low-resistance-risk groups,’’ he explains.

“Later in the season, to control tuber blight and avoid issues in storage, Proxanil + Ranman Top (cyazofamid) are rated most effective on the Euroblight table.”

Editor’s notes

 ABOUT UPL

UPL Ltd. (NSE: UPL & BSE: 512070, LSE: UPLL) is a global provider of sustainable agriculture products and solutions, with annual revenue exceeding $6bn. We are a purpose-led company. Through OpenAg®, UPL is focused on accelerating progress for the food system. We are building a network that is reimagining sustainability, redefining the way an entire industry thinks and works – open to fresh ideas, innovation, and new answers as we strive towards our mission to make every single food product more sustainable. As one of the largest agriculture solutions companies worldwide, our robust portfolio consists of biologicals and traditional crop protection solutions with more than 14,000 registrations. We are present in more than 130 countries, represented by more than 10,000 colleagues globally.

For more information about our integrated portfolio of solutions across the food value chain including seeds, post-harvest, as well as physical and digital services, please visit upl-ltd.com and follow us on LinkedInTwitterInstagram and Facebook.

Contact: Gemma Nokes
Head of Marketing (UK and Ireland)

m: +44 (0)7788 308 928
e: [email protected]