Oral Presentation Australasian Plant Pathology Society Conference 2025

Towards Durable Resistance: Neutralising Oat Sensitivity Loci to Reduce the Impact of Septoria Avenae Blotch in Australian Oat Varieties  (118121)

Kealan G Hassett 1 , Eiko Furuki 1 , Kasia Rybak 1 , Grace Foley 1 , Fiona Kamphuis 1 , Huyen TT Phan 1
  1. Curtin University, Perth, WA, Australia

Australia’s oat industry faces significant production capacity constraints due to Septoria avenae blotch (SAB), a stubble-borne disease caused by Parastagonospora avenaria f.sp. avenae. SAB is widespread across all cereal-growing regions, with Western Australia, Australia’s primary production region, reporting nearly universal infection across oat crops. Further, the disease can cause grain yield losses of up to 50%, reduce hay quality, and in severe cases, lead to crop lodging. Despite the economic and agronomic impact, commercial oat varieties remain moderately susceptible, typically forcing growers to rely on crop rotations and fungicides, which can be costly and unsustainable long-term.

 

The Oat Septoria Research Consortium (OSRC), supported by GRDC, unites Australia’s leading research groups to develop new oat varieties with durable genetic resistance. Program 3 of OSRC aims to neutralise host susceptibility by targeting interactions between fungal necrotrophic effectors (NEs), key virulence factors that manipulate host-cell processes to promote disease, and their corresponding oat sensitivity loci.

CCDM researchers have identified the first fungal effectors of SAB, leveraging lessons learnt in effector biology from wheat-pathogen interactions. Program 3 is now working to:

  • Expand the known Septoria NE set,
  • Characterize their molecular interactions with oat host cells,
  • Identify and neutralise susceptibility loci that mediate disease progression.

 

By the end of 2027 Program 3 of OSRC aims to provide Australian oat breeders with access to germplasm with SAB resistance ratings of MRMS to MR, along with molecular selection tools to facilitate the removal of sensitivity loci. This research consortium represents a crucial step towards developing high-yielding and disease-resistant oat varieties, improving production stability, and reducing grower reliance on chemical control. This presentation focuses on the initial findings and current works by the Program 3 of OSRC team.