Investment

The production of oat in Australia increases by about 10 to 15% annually due to growing domestic and export demand for milling oats and oaten hay. Human health benefits, agronomic advantages as a break crop in rotations and its frost tolerance are reasons for oat's growing popularity. Increasing demand has shifted oat production from traditional high-rainfall oat-growing areas to regions, including low-rainfall environments, not traditionally known for growing oat.

To develop better adapted and improved varieties, environmental challenges are to be addressed through pre-breeding research focussed on the constraints that have the biggest impact on oat crop production. Cereal cyst nematodes, stem and crown rust, Red Leather Leaf disease, and Septoria blotch in WA, are the most important biotic stresses in oats, with drought the key abiotic stress. Resistance to these diseases and tolerance to drought are key oat-breeding priorities.

Outputs:

1. 1. Identification of oat lines carrying new sources of stem and crown rust resistance genes in an adapted background and provision of them to the National Oat Breeding Program (NOBP).
   2. Identification of oat lines carrying diverse sources of CCN resistance combined with CCN tolerance in adapted background and provision of them to NOBP.
   3. Identification of oat lines with improved resistance to Septoria avenae.
   4. A cultivation and inoculation protocol to enable oat breeding lines to be assessed for resistance to Red Leather Leaf fungus.
   5. A toolbox of closely-linked, user-friendly markers for marker-assisted-selection of the rust and CCN resistance genes identified in this project.
   6. Generation of a knowledge base on oat performance under low-rainfall conditions comprising the critical period for yield determination, preliminary screening and determination of phenological groups and phenotyping for drought adaptation.

Approach and Expertise:

Current varieties, breeding lines and nationally and globally-sourced oat accessions including wild relatives will be screened for the afore-mentioned traits. Existing mapping populations will be used to investigate the inheritance of resistance to stem and crown rust and CCN. These mapping populations form the basis of molecular marker developments that will facilitate the introgression of the resistance traits into the breeding process. The analysis of the different diseases will be carried out in growth chambers, glasshouses and disease nurseries in the field.

To assess the oat germplasm for the improvement of drought tolerance, secondary plant traits that can contribute to better performance under low water availability, such as flowering time and maturity, early vigour, canopy temperature, yield components, leaf chlorophyll and water-soluble carbohydrate content, will be evaluated in well-watered and drought-stressed conditions using rain-out shelters.

This project is a collaborative enterprise by researchers from SARDI and the Cereal Rust Research Centre, University of Sydney.