A team of Agricultural Research Service (ARS) and university scientists has released two new oat germplasm lines, CDL-111 and CDL-167, to strengthen defenses against crown rust, the most damaging fungal disease affecting oats. Crown rust, caused by Puccinia coronata f. sp. avenae, can reduce grain yields by up to 50% if left untreated.
The new lines are designed to be crossed with commercial oat varieties, introducing fresh sources of resistance. While most existing oat varieties rely on “seedling resistance” from one or two genes, the crown rust fungus evolves quickly, reducing the effectiveness of these defenses within three to five years.
To overcome this, the team employed a strategy called gene stacking, crossing cultivated oats with wild relatives to introduce “adult plant resistance,” which slows the disease without full immunity. The two new lines underwent extensive trials, including testing in disease-prone nursery plots, where they outperformed other plants.
These germplasm lines are now available for use in breeding programs through ARS agreements, providing breeders with a powerful combination of seedling and adult plant resistance to protect oat crops.
Sabrina Halvorson
National Correspondent / AgNet Media, Inc.
Sabrina Halvorson is an award-winning journalist, broadcaster, and public speaker who specializes in agriculture. She primarily reports on legislative issues and hosts The AgNet Weekly podcast. Sabrina is a native of California’s agriculture-rich Central Valley.