Fungicide-Resistant Net Blotch in Barley Seed Threatens Next Crop, UniSQ Researchers Warn

University of Southern Queensland (UniSQ) researchers have discovered that barley seed can carry fungicide-resistant net blotch, a disease that could be transferred to seedlings and compromise the next crop. This emerging research highlights a critical pathway for the spread of resistance, as the pathogen survives on seed and infects new plants even before fungicides are applied. Net blotch, caused by the fungus Pyrenophora teres, is a major barley disease that reduces yield and grain quality, and resistance to common fungicides makes it harder to control. The findings suggest that seed-borne transmission may be an overlooked factor in the persistence and spread of resistant strains across growing regions. For growers, this means seed testing and treatment could become essential tools in managing the disease and preventing resistance from establishing early in the season. The research underscores the need for integrated disease management strategies, including rotating fungicide modes of action and using certified seed. As barley is a key crop for malt and feed, protecting its productivity is vital for the agricultural economy. The study points to future work on seed treatment efficacy and the development of resistant barley varieties.