THE delicately patterned Barberry Carpet moth is one of England’s species most at threat of extinction. But it's conservation is complicated. The moth’s host plant is Barberry (Berberis vulgaris), which helps the overwintering cycle for wheat stem rust, one of the most devastating diseases affecting wheat. It acts as a seasonal bridge for the disease. As a result and to manage the disease, the shrub was eradicated from many hedgerows in the 19th century and this was thought to have broken the disease cycle.

The Barberry Rust Explorer (BarbRE) program is a new citizen science project being launched on 3 April. In the first detailed study of barberry bushes for rust infection in the UK, volunteers, conservationists, scientists and farmers will work together to develop new strategies on how to prevent wheat stem rust while conserving the moth going forwards. The project will be focussed on better understanding the life cycle of the stem rust pathogen to protect cereals from future outbreaks, whilst also understanding how Barberry plants can be managed to promote conservation of this precious species.

Mark Parsons of Butterfly Conservation said: “Barberry still occurs widely in the countryside and despite this there have been no wheat rust issues in recent times. However, while the Barberry Carpet moth is an endangered species, restricted to just a handful of sites in this country, we are still concerned about the potential risk from stem rust and the impact it could have on food security. By working together, we can reach a consensus on the best way to manage this complex issue and maintain part of our natural heritage, whilst also reducing any possible threat from stem rust.”

Although no infections of wheat stem rust have been recorded in the UK since 2013, increased incidence of the disease in Western Europe is worrying as most of our wheat species are susceptible.

Dr Diane Saunders from the John Innes Centre said: “Understanding how rust strains diversify and being able to accurately identify the cereal-infecting forms is vital for future bio-security. This knowledge may also suggest alternative methods of disease control.”

Anyone interested in conservation and farming can get involved in the project by using the iNaturalist app to report the location of Barberry bushes. These can then be checked by the BarbRE team for stem rust infection. The location information will directly inform the development of risk models, which will be invaluable if wheat stem rust does re-emerge in the UK.

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