Fusarium Crown Rot Reduces Water Use and Causes Yield Penalties in Wheat under Adequate and above Average Water Availability

The cereal disease Fusarium crown rot (FCR), caused by the fungal pathogen Fusarium pseudograminearum, is a worldwide major constraint to winter cereal production but especially in Australia's northern grain's region (NGR) of NSW and Queensland. Conventionally, FCR induced yield penalties are associated with semi-arid water-limited conditions during flowering and grain-filling. In this study, yield penalties associated with FCR infection were found to be significant under both adequate and above average water conditions which has implication for global wheat production in more favorable environments. This research was conducted to understand the impact of FCR on water availability, yield and grain quality in high protein bread and durum wheat varieties in controlled environment and replicated field experiments across three locations in the NGR over a two-year period. Under controlled conditions, FCR infection significantly decreased water use by 7.5% with an associated yield reduction of 9.5% irrespective of water treatment. Above average rainfall was experienced across all field experimental sites in both 2020 and 2021 growing seasons. The field studies demonstrated a decrease in water use of upwards of 23% at some sites and significant yield penalties across all cultivars of up to 18.4% in natural rainfed scenarios to still 13.2% with further supplementary irrigation.