Researchers identify fungus that infects another parasitic fungus

Researchers at North Carolina State University discovered that a fungus called Ampelomyces frequently infects powdery mildew, a common plant disease.

The team analyzed more than 600 dried samples from the NC State herbarium, which contained specimens collected across 28 countries over the last 150 years. Because powdery mildews cannot be grown in a lab, the scientists used these historical museum samples and data from GenBank, a public database of genetic sequences, to track the parasite.

The study revealed that approximately 7% of the powdery mildew specimens analyzed were infected by the Ampelomyces fungus. Michael Bradshaw, an assistant professor at the university, explained that these hyperparasites, which are parasites of other parasites, could help scientists develop better ways to control plant diseases. He noted that different strains of Ampelomyces have different levels of host specificity, which might make some more effective at containing mildew than others.

The researchers also found that data quality in public databases can be unreliable. They discovered that about 15% of the specimens in GenBank labeled as Ampelomyces were actually misidentified. Bradshaw explained that because these parasites are difficult to identify, incorrect data entered into the system by one person can lead to others using that wrong information, creating a cycle of inaccurate classifications.