|ZIMMER, CHRISTIANO - Federal University Of Rio Grande|
|MCNISH, IAN - University Of Minnesota|
|Esvelt Klos, Kathy|
|EICKHOLT, DAVID - Pepsico|
|ARRUDA, KLEVER - Agronomic Institute Of Paraná (IAPAR)|
|PACHECO, MARCELO - Federal University Of Rio Grande|
|SMITH, KEVIN - University Of Minnesota|
|FEDERIZZI, LUIZ - Federal University Of Rio Grande|
Submitted to: Molecular Breeding
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 7/20/2021
Publication Date: 7/22/2021
Citation: Zimmer, C.M., Mcnish, I.G., Esvelt Klos, K.L., Eickholt, D.P., Arruda, K.M., Pacheco, M.T., Smith, K.P., Federizzi, L.C. 2021. Genome-wide association mapping for kernel shape and its association with beta-glucan content in oats. Molecular Breeding. Article 20605. Available: https://doi.org/10.1002/csc2.20605.
Interpretive Summary: Variation in multiple genomic regions controls kernel shape-related traits in oats. Quantitative Trait Loci (QTL) contributing to variation in kernel length are located on three chromosomes: Mrg06, Mrg21, and Mrg24. Kernel width and kernel thickness are correlated. Both are influenced by variation on Mrg13. Kernel width and kernel thickness are negatively correlated with beta-glucan content. Selection of wider and thicker kernels may decrease oat beta-glucan content.
Technical Abstract: Kernel shape and beta-glucan content are important attributes for oat millers. The identification of genomic regions controlling these traits, as well as their effect on phenotype, will enable rapid gain from selection. The objectives of this study were to: i) to identify genetic variation associated with kernel shape in an oat panel adapted to subtropical environments using high-throughput phenotyping; and ii) clarify the relationship between kernel shape and beta-glucan content in oats. An elite oat panel comprised of 407 inbred lines was assessed in Londrina and Eldorado do Sul, Southern Brazil. Genome-wide association analyses were performed for each environment separately and also using a multi-environment analysis. Phenotypic and genetic correlation coefficients were estimated between kernel shape-related traits and beta-glucancontent. Genomic regions influencing kernel length were identified on Mrg06, Mrg21, and Mrg24. Kernel width and kernel thickness are genetically correlated and share a quantitative trait locus, located on Mrg13 of the oat consensus map. Phenotypic and genetic correlations were found between kernel-shape related traits and beta-glucan content, indicating a negative relationship between kernel width or kernel thickness and glucan content. Oat breeding programs that aim to maintain minimum levels of beta-glucan for nutrition and minimum kernel widths for milling will need to screen for both traits, otherwise indirect selection will lead to unfavorable results. However, the negative correlation was not too strong (-0.4), suggesting that improvement for both traits can be made simultaneously.