Researchers in China identified a fungus called Clonostachys rosea as the cause of brown rot disease affecting Gastrodia elata (Tian Ma), an important medicinal orchid plant. The disease causes brown spots on tubers that expand and darken, significantly reducing crop yield and quality. The study involved detailed examination of the fungus under microscopes, genetic analysis, and confirmation that the fungus could cause disease in healthy plants. These findings will help farmers prevent and control this disease through proper soil management and selection of healthy seed tubers.