​Whether you opt for a crunchy granola bar, mushy bowl of oatmeal, or smooth glass of oat milk, it is clear oats are gaining popularity—both with consumers and breeders. Oats provide a naturally gluten-free source of nutrition, with proven health benefits for humans and livestock.

However, oats have long produced smaller yield gains compared to other cereal grains. Oat production is primarily affected by diseases such as crown rust and powdery mildew, which occur in most oat-producing countries. Use of fungicides is not economically feasible and may also develop resistance in the pathogen population.

Consequently, developing host resistance is recommended. While over 100 genes effective against crown rust exist, few chromosomal locations, or quantitative trait loci (QTL), are known. According to this article's corresponding author Dr. Belayneh Admassu Yimer of the University of Idaho, the information gap has “limited the utilization of genomic tools in oat breeding and caused difficulty when determining the novelty of newly identified QTL."

Regarding powdery mildew in oats, only 11 effective genes exist, but none prove effective to all powdery mildew isolates. This study identified multiple genes, including novel powdery mildew QTL, that are effective against multiple diseases in one oat line. The same oat populations were screened for crown rust resistance in Aberdeen, Idaho and for powdery mildew at the University of Aberystwyth in the United Kingdom.

This discovery will broaden and diversify resistance sources. “In general, the novel powdery mildew QTL and molecular markers identified in our study will facilitate the development of oat varieties with durable resistance to crown rust and powdery mildew diseases," said Admassu Yimer.

The research of Admassu Yimer and colleagues, in a collaboration that crossed the Atlantic, widens our understanding of host-pathogen interactions at the molecular level, which will positively impact oat genomics, breeding, and pathology, especially regarding disease resistance. This new study fills some of those gaps, which excites the researchers most.

Find more details about this study in Volume 112, Number 6, June 2022 of Phytopathology.

Keep up with the researchers and/or their affiliations on Twitter! Follow @UidahoExtension, @HowarthOats, and ​@AberUni.