Breeding Oat Varieties With Durable Leaf Rust Resistance And High Forage Yield For The Northern Cropping Region

Summary

Leaf rust has an adverse effect on quality and quantity of forage oat crops.  The 16 oat varieties released in Queensland in the previous 10 years have each been overcome by leaf rust, most of them within one or two years from release.  The rapid breakdown was due to the ability of the fungus to mutate into a new and virulent form when challenged with single leaf rust resistance gene in these varieties.  Therefore, a program to develop oat varieties with a more durable form of leaf rust resistance was a high priority.  
This project sought to develop a durable form of leaf rust resistance by "pyramiding" a multiple number of resistance genes into a variety.  Five elite experimental varieties were bred and considered for commercial release.  All of these varieties had high forage yield and high levels of resistance to leaf rust, and similar attributes to the variety Algerian i.e. fine stems and leaves and low growing point.  However, the project review meeting decided that the commercial market for this type of forage oat variety was not sufficiently large to justify a commercial release.