An example of stem rust. Photo by John Innes Center
Feb. 8 (UPI) -- Scientists have confirmed the first case of stem rust in Britain in 60 years. In a new study, published this week in the journal Nature Communications Biology, researchers warn of the risks posed by a resurgence of the forgotten plant pathogen.
Since scientists were first alerted to the infected wheat plant in 2013, scientists at the John Innes Center in Norwich, England, have been studying the pathogen. Their analysis linked the infection to the Digalu race of the fungus.
The strain was responsible for a large crop-killing outbreak in Ethiopia in 2013. The Digalu fungus also caused smaller outbreaks in Sweden, Denmark and Germany.
Scientists have determined recent shifts in Europe's climate and weather patterns could be conducive to stem rust outbreaks among wheat and barley crops.
Wheat stem rust is one of several pathogens that uses the hedgerow shrub Barberry, Berberis vulgaris, as an alternate host. The plant plays an important role in the life cycle of the fungi. In recent years, Barberry populations have been growing in Europe.
Prior to the latter half of the 20th century, farmers had mostly ridded Europe of Barberry, after noticing its consistent presence near fields infected by stem rust. In recent decades, Barberry shrubs have been planted in an effort to save the Barberry Carpet moth.
So far, the 2013 infection has proven an isolated incident. But researchers worry rising temperatures will facilitate the pathogen's return.
"There is the potential for stem rust to become an ever-increasing threat across Europe and so research, such as this, will help to underpin breeding for resistance in the future," cereal pathologist Paul Fenwick said in a news release.
Scientists say more work must be done to breed stem rust resistance among cereal varieties. Farmers must also coordinate with conservationists to ensure Barbary habitat is protected without putting cereal crops at risk.
"We are very concerned about the potential risk from the possible re-establishment of stem rust in this country and the impact it could have on agriculture and the environment," said Mark Parsons of Butterfly Conservation. "The Barberry Carpet moth is an endangered species restricted to just a handful of sites in this country, it being reliant on Common Barberry for survival. We are, therefore, pleased to be working closely with the John Innes Centre both to minimize the potential risk from cereal rust, but also to enhance the populations of the Barberry Carpet, and therefore increase its chances of survival in this country."
Because the fungal spores that use Barberry as a host cannot travel very far, the shrub only puts crops at risk if it is planted in close proximity to cereal fields.
