A Novel Strain Burkholderia theae GS2Y Exhibits Strong Biocontrol Potential Against Fungal Diseases in Tea Plants (Camellia sinensis)

Background: Tea plants (Camellia sinensis) are widely cultivated cash crops. However, fungal diseases lead to significant reductions in both the yield and quality of tea. Therefore, searching for economical, eco-friendly, and efficient biological control measures is crucial for protecting tea plants from pathogenic fungi. Methods: The confrontation assays were performed to identify the antagonistic bacteria against tea pathogenic fungi and evaluate the antifungal activity of these bacteria. Results: Here, three tea pathogenic fungi were identified:Colletotrichum siamenseHT-1,Diaporthe phaseolorumHT-3, andFusarium fujikuroiHT-4. Notably,D. phaseolorumwas the first to be reported in tea plants in China. Some tea pathogenic fungi showed a high relative abundance, suggesting a potential disease risk in tea plantations. Strain GS2Y, isolated from tea rhizosphere soil, exhibited strong antifungal activity against tea pathogenic fungi and represented a novel species within the genusBurkholderia, designated asBurkholderia theae. GS2Y could directly inhibit tea pathogenic fungi by disrupting the cellular structures and protect tea plants from fungal diseases caused byC. siamenseHT-1 andD. phaseolorumHT-3. Conclusions:B. theaeGS2Y might function as a potentially valuable resource for biocontrol agents, laying the foundation for the development of strategies to manage fungal diseases in tea plants.