Scottish Agronomy has declared its support for the Fight Against Blight (FAB) campaign for 2023 by becoming one of the sponsors – Eric Anderson, the company’s senior agronomist has announced.

Late blight is a particular concern for the potato industry because different strains of the pathogen evolve, some of which have insensitivity to currently approved plant protection products. Suspected blight samples are sent to the James Hutton Institute by Blight Scouts, where they are analysed to detect the specific strain, and the results returned to the scout.

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Mr Anderson said: “At Scottish Agronomy, which is a farmer-owned co-operative, we are grateful to David Cooke, Alison Lees, Jamie Smith and their colleagues at JHI for pulling together collaborative sponsorship from companies and organisations for support of Fight Against Blight in 2023.”

The insight provided has been essential to furthering our understanding of the blight dynamics in Great Britain and continental Europe. Tracing clonal spread and survival of late blight is critical and late blight management strategies, especially fungicide programmes, need to be constantly updated to reflect the risk.

Knowing which strains are out there helps make the most appropriate fungicide choice, which supports product stewardship by slowing down any resistance evolution, he added.

“We need to ensure we have a robust, sustainable and profitable industry able to effectively assess the threats, so that the appropriate action can be taken. This was one of the main reasons behind our decision to sponsor the campaign,” he said.

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By the end of May, active blight outbreaks had already been seen, not only in Cornwall and Kent but also reported beyond these areas and are soon likely to be found in Scotland.

“The FAB campaign is going to be crucial this year because there is a new threat from the blight strain known as EU_43, which was first detected in Denmark in 2018, and since then has seen incidence escalate there, but also move into Belgium, the Netherlands and even Portugal.

“The main concern is that it has been found to be resistant to mandipropamid, with cross resistance to fungicides in the same CAA group, including benthiavalicarb, dimethomorph, and valifenalate.

“The key will be not be making fungicide programmes more complicated than they need to be. We need to use the current research evidence to come up with practical mixing partners and programmes,” he pointed out.

He highlighted that because of Denmark’s environmental policy – which is even more stringent than that of the wider EU – farmers there had fewer actives for control of late blight. In addition, Danish authorities revoked the approval of cyazofamid with effect from January, 2023, because of metabolites being found in ground water, leaving the toolbox even more depleted.

“Taking a wider perspective, the ‘European Green Deal’ is causing greater selection pressure on the remaining actives, which will further encourage resistance shifts – and in Britain we really need to avoid this," pointed out Mr Anderson.

“There have been more than one introduction of a new fungicide mode of action and subsequent losses of efficacy, due to the emergence and selection of resistant pathogen strains.

“Fundamentally, the rate of loss of effective fungicides threatens to exceed the rate of introduction. It is, therefore, critical to develop and implement effective fungicide management methods to slow the selection for fungicide-resistant strains in the pathogen population.“

“Although this strain has not yet been found in GB, that does not mean it has not yet arrived here; and we need to be on our guard. At Scottish Agronomy, we are working to ensure that our growers have the earliest possible information which will help them make informed decisions about their crop and how to get the most from it.

“We are pleased to be contributing to FAB as a means of ensuring that our industry continues to have access to the best information available so that together we can grow in strength and profitability.”

* The FAB service had been previously provided via funding from the AHDB Potato levy, and since its demise was funded by Scottish Government last season. Others in the industry consortium supporting FAB, includes UPL, BASF, Bayer, Certis Belchim, Corteva, Syngenta, Agrii, Agrovista, FMC, Frontier, GB Potatoes, McCain, Seed Potato Organisation, Agrico and Branston.