An in-depth historical phenotypic and genetic assessment of oat (Avena sativa L.) breeding at the University of Illinois

Authors: SCHEFFEL, SHEILA - UNIVERSITY OF ILLINOIS URBANA-CHAMPAIGN; KOLB, FREDERIC - UNIVERSITY OF ILLINOIS URBANA-CHAMPAIGN; SCOFIELD, STEVEN; FIELDER, JASON - U.S. DEPARTMENT OF AGRICULTURE (USDA); RUTKOSKI, JESSICA - UNIVERSITY OF ILLINOIS URBANA-CHAMPAIGN; ARBELAEZ, JUAN - UNIVERSITY OF ILLINOIS URBANA-CHAMPAIGN

Submitted to: Crop Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 4/29/2026
Publication Date: 5/28/2026
Citation: Scheffel, S., Kolb, F.L., Scofield, S.R., Feidler, J., Rutkoski, J.E., Arbelaez, J.D. 2026. An in-depth historical phenotypic and genetic assessment of oat (Avena sativa L.) breeding at the University of Illinois. Crop Science. https://doi.org/10.1002/csc2.70312Digital Object Identifier (DOI).
DOI: https://doi.org/10.1002/csc2.70312Digital Object Identifier (DOI)

Interpretive Summary: Public breeding programs have been responsible for developing the majority of oat varieties grown by US farmers. Numerous factors have contributed to a sharp decline in US oat production over the last 60 years and concomittantly, the number US oat breeding programs have reduced. Today only five public breeding programs remain active. Despite the decline in production oat remains important for US agriculture. This report examines the genetic diversity present within the University of Illinois oat breeding program. Knowing this is critical for understanding the potential this program has for developing improved varieties that are adapted for future conditions. A wide range of genetic analyses were conducted from which it was concluded that while this program has developed many new varieties with improved agronomic properties, it has maintained ample diversity to remain a valuable resource for supporting future oat production.

Technical Abstract: Public oat breeding capacity has historically shrunk. Therefore, it is essential to evaluate the effectiveness of existing programs to ensure they continue to deliver value to stakeholders, including farmers, millers, and consumers. We evaluated the performance of the University of Illinois Oat Breeding Program (UIOBP) by quantifying realized genetic trends for key agronomic, grain quality, and disease resistance traits. We also assessed the effect of abiotic stress and genetic diversity to inform future breeding decisions. We analyzed genotypic, pedigree, historical weather, and phenotypic data (2001-2019) from the UIOBP. Genetic trends were estimated using mixed models and the control population method. We quantified heritability, genetic correlations, rates of genetic gain, and the effects of temperature on yield and test weight, and assessed genetic diversity using marker data, pedigree reconstruction, and population structure. Significant desired genetic trends were observed for yield (44 kg ha'¹ yr'¹), test weight (1.6 g L'¹ yr'¹), and plant height (–0.31 cm yr'¹), while heading date, Barley Yellow Dwarf Virus, groat content, and thins showed no significant change. Genetic diversity analyses revealed weak population structure and slightly reduced effective population size in recent parental lines. Temperature during critical reproductive periods reduced yield and test weight. The UIOBP has maintained genetic diversity while achieving sustained gains in yield, test weight, and reduced plant height through recurrent selection and elite introgressions. However, limited progress in milling traits highlights areas for improvement. These findings demonstrate the continued value of public oat breeding and guide future strategies.