How the Global Tea Industry Copes With Fungal Diseases - Challenges and Opportunities.

Tea ( [L.] O. Kuntze) is a plantation crop, grown commercially in Asia, Africa, and South America. Among biotic threats to tea production, diseases caused by fungal pathogens are most significant. Worldwide, tea plants are challenged by several root, stem, and foliar diseases. Foliar diseases, blister blight, gray blight, and brown blight are particularly important as they adversely affect the bud and the two youngest leaves, causing loss of harvestable shoots. Over the past several decades, climate change and field management practices have influenced the risk of crop damage by several fungal pathogens, as well as the development and spread of diseases. Management interventions, such as the adoption of good cultural/agronomic practices, use of fungicides and microbial biocontrol agents, plant defense elicitors, and deployment of resistant cultivars, have mitigated damage to tea plants caused by fungal diseases. A clearer understanding of knowledge gaps and the benefits of plant disease management strategies available is needed. The present article reviews the prevailing knowledge of major fungal pathogens of the tea crop, their genetic variability, the damage they cause and its economic impact, and the need for new disease management strategies as climate change intensifies. We will also emphasize important knowledge gaps that are priority targets for future research.