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ARS Home » Plains Area » Fargo, North Dakota » Edward T. Schafer Agricultural Research Center » Cereal Crops Improvement Research » Research » Publications at this Location » Publication #416593
Research Project: Improvement of Disease and Pest Resistance in Barley, Durum, Oat, and Wheat Using Genetics and Genomics

Location: Cereal Crops Improvement Research

Title: Understanding the genetic basis of stem rust resistance in southeastern US oat through genome wide association stud

Author
item ACHARYA, J. - University Of Florida
item BABAR, M.A. - University Of Florida
item KHAN, N. - University Of Florida
item MCBREEN, J. - University Of Florida
item SIGNORINI, V.S. - University Of Florida
item KUNWAR, S. - University Of Florida
item ADEWALE, S. - University Of Florida
item Esvelt Klos, Kathy
item HARRISON, S. - Louisiana State University
item DEWITT, N. - Louisiana State University
item FURLAN, F. - Louisiana State University
item Fiedler, Jason
item Nandety, Raja Sekhar
item Osenga, Mary
item BOYLES, R. - Clemson University

Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: 6/21/2024
Publication Date: 7/21/2024
Citation: Acharya, J., Babar, M., Khan, N., Mcbreen, J., Signorini, V., Kunwar, S., Adewale, S., Esvelt Klos, K.L., Harrison, S., Dewitt, N., Furlan, F., Fiedler, J.D., Nandety, R., Osenga, M.M., Boyles, R. 2025. Understanding the genetic basis of stem rust resistance in southeastern US oat through genome wide association stud. Meeting Abstract.

Interpretive Summary:

Technical Abstract: Stem rust (SR), caused by Puccinia graminis f. sp. avenae Eriks (Pga), presents a considerable threat to oat production, leading to yield and quality reductions. Ongoing efforts in southeastern US universities aim to develop oat varieties with varying resistance levels to this pathogen. However, the specific genetic factors governing the response of southern oat varieties to SR remain elusive. This study seeks to elucidate these genetic mechanisms. Utilizing the Southern Oat Association Panel (SOAP) comprising 440 elite oat lines from public breeding programs in the Southern US, we conducted experiments at selected sites in Citra, FL, Castroville, TX, Baton Rouge, and Winnsboro, LA, known for oat rust disease prevalence. Employing a randomized complete block design with three replicates, susceptible checks were strategically placed to ensure uniform infection distribution. Days to heading and relative maturity were considered as covariates for subsequent analyses. SR phenotypes were visually evaluated during mid and late dough stages in the field, assessing infection response (rated R to S) and severity (rated 0 to 100) according to modified Cobb scale. Additionally, the Average Coefficient of Infection (AIC) was calculated. Genotyping was performed using the genotype by sequencing (GBS) method, with data filtered for multiallelic and monomorphic SNPs. SNPs with a relative minor allele frequency below 0.05 and those missing more than 20% of data were excluded. Preliminary genome-wide association studies (GWAS) revealed significant associations of single nucleotide polymorphisms (SNPs) with stem rust using Bonferroni correction as a threshold. Multiple marker trait associations were identified and a consistent marker-trait association for stem rust resistance on chromosome 1A was identified across all locations and over time. These findings highlight a notable level of resistance against virulent stem rust races within the SOAP genotypes that could help to explore potential utilization of these associations.