First Report of Coffea arabica Fruit Rot Disease Caused by Fusarium coffeibaccae in China

<i>Coffea arabica</i>, a popular beverage ingredient, is prized for its rich chemical composition, which has demonstrated significant positive effects in terms of antioxidant, anti-inflammatory, neuroprotective, and metabolic health. In November 2024, fruit rot with a 15% incidence was observed on <i>C. arabica</i> in Menglian city, Yunnan province, China. Symptoms began as irregular black spots that turned necrotic, wrinkled, and cracked. Fungal isolates from lesions showed morphological characteristics consistent with <i>Fusarium coffeibaccae</i>. Morphological data were supplemented with phylogenetic analyses based on three loci (<i>ITS</i>, <i>TEF1-α</i>, <i>RPB2</i>), and sequences were deposited in GenBank as for <i>ITS</i> (PV211189 and PV211190), <i>TEF1-α</i> (PQ867811 and PQ867812), and <i>RPB2</i> (PV261064 and PV261065). Koch's postulates were fulfilled on attached fruits. After 17 days at 25 °C with 70% humidity, typical rot symptoms appeared on inoculated fruits, while controls remained symptom-free. This is the first report of <i>C. arabica</i> fruit rot caused by <i>F. coffeibaccae</i> in China. This study aims to identify the aetiological agent of recently observed coffee fruit rot in Yunnan and to characterize <i>F. coffeibaccae</i>. It provides the first baseline data for targeted monitoring and sustainable control of <i>F. coffeibaccae</i>-mediated fruit rot in China's expanding coffee sector.