Stubble trouble: mapping Fusarium crown rot survival under different cereal stubble management scenarios

Abstract

The adoption of stripper-front headers, light tillage and rotations with shorter-stature break crops is increasing in northern New South Wales cropping systems. The effect of these practices on survival of Fusarium crown rot inoculum in cereal stubble is unknown but may impact future disease risks. Field experiments at Narrabri and Breeza in NSW examined whether reducing the harvest-height of a cereal crop infected with Fusarium crown rot (Fusarium pseudograminearum, Fp) limits post-harvest pathogen colonisation. Pathogen survival was assessed within standing cereal stubble during a chickpea break crop in 2020. Fp was recovered higher within stems in tall and medium harvest-height treatments in May 2020 compared to harvest levels in 2019. This confirms that wet fallow conditions allow Fp to saprophytically colonise cereal stubble and shortening harvest-heights could limit this inoculum production. Performance and disease levels in a successive wheat crop is required to verify potential benefits of this practise.