According to Hort Innovation, Australia produces an average of 247,423 tonnes of onions annually, valued at approximately $164.8 million. Major production regions are South Australia (48%), Tasmania (23%), and Queensland (10%).

In onion crops, many soil-borne and foliar fungal diseases affect onion germination, root and foliage health and with that yield, quality and profitability.

Broader economic implications of fungal diseases are reduced marketability and storage/shelf life. Increased input costs are often required for fungicides, soil testing, and cultural control methods which add to production expenses. Disease management commonly requires more labour and equipment use in the field and post-harvest. Paddocks infected with persistent diseases cannot be used for onion production, potentially reducing the overall productive area for onions. Infected land also poses a biosecurity risk for ‘clean’ land due to soil and water movement between paddocks and regions.

Fungal disease management requires an integrated approach to avoid fungicide resistance. This includes cultural control methods such as crop rotation and or cover crops to break the disease cycle and minimise the inoculum for the following season.