Scientists have warned that blueberries could be wiped out a fungus rapidly-spreading worldwide.
Caused by a two different strains of fungus, the disease appears as a white powdery mildew on plants, lowering crop yields and increasing the dependency on fungicides.
The team found the Erysiphe vaccinii has spread worldwide over the past 12 years.
One strain found its way to China, the world’s largest producer, Mexico and California, while a different strain wound up in Morocco, Peru and Portugal.
Michael Bradshaw, assistant professor of at North Carolina State, said: ‘This is a hard organism to control. If you’re sending plant material across the world, you’re likely spreading this fungus with it.’
The team also discovered that the fungus found in blueberries outside the use appeared to solely reproduce asexually.
Both sexual versions of the fungus are not required in reproduction, whereas the fungus reproduces sexually and asexually in the US.
The study estimated a cost range of between $47 million and $530 million annually to the global blueberry industry as more than four billion pounds of blueberries are sold annually worldwide.
Scientists have warned that blueberries could be wiped out a fungus rapidly-spreading worldwide. Caused by a two different strains of fungus, the disease appears as a white powdery mildew on plants, lowering crop yields and increasing the dependency on fungicides
Map displaying occurrences of powdery mildew bacteria globally taken from recent University of North Carolina study showing high concentrations of the fungus in the north eastern regions of the United States
The disease is thought to have originated in the eastern US and has mostly remained contained in that area, although minor outbreaks appear to have surfaced in southern California.
Additionally, the study comes with a warning to the US Pacific Northwest Region, as the rainy climate provides a perfect breeding ground for the powdery mildew to infiltrate crops that have thus far appeared to avoid any disease within that area.
The powdery mildew covers the host plants and functions almost parasitically.
Depleting the plant nutrients and slowing the photosynthetic process, the fungus grows while simultaneously keeping the host alive.
However, with the discovery comes hope in ability to more easily identify and thus slow and more comfortably manage the spread of the disease.
As the fungus that causes the powdery mildew in blueberries can be difficult to identify, researchers at North Carolina State developed a database that can be used by scientists and farmers alike to report and view previously reported data about the disease.
‘This platform allows growers to enter their data and learn which specific strain is in their fields,’ Bradshaw said.
‘That’s important because understanding the genetics can warn farmers about which strain they have, whether it is resistant to fungicides, and how the disease is spreading, as well as the virulence of particular strains.’
Powdery mildew E. Vaccinii displayed on leaves of host blueberry plants
Microscopic photography of isolated portions of the fungus
While the fungus has predominantly been identified in blueberry plants, the species has been found to infect wheat, hops, grapes, and strawberries plants.
The blueberry plant is native to America and is believed to be one of the first edible fruit-producing plants discovered by native people following the last ice age.
In addition to being picked and eaten fresh, Native Americans incorporated blueberries into a variety of dishes that include soups, stews, preserves and puddings.
However, early uses of the blueberry extended far beyond cultural cuisine, spilling into medicinal uses in combination with roots, stems, leaves and flowers.
Known today as the highbush variety, the plant natively stretched from the arctic plains across what is now the United States down through Mexico and into some parts of South America.
Although this information about the disease is surfacing only recently, samples that were analyzed in the study conducted by the University of North Carolina included a specimen collected by the North American herbarium over 150 years ago.
