Association mapping of sponge cake volume in U.S. Pacific Northwest elite soft white wheat (Triticum aestivum L.)

Authors: Thompson, Yvonne; CARTER, ARRON - Washington State University; Ward, Brian; KISZONAS, ALECIA - Washington State University; Morris, Craig

Submitted to: American Association of Cereal Chemists Meetings
Publication Type: Proceedings
Publication Acceptance Date: 10/19/2021
Publication Date: N/A
Citation: N/A

Interpretive Summary:

Technical Abstract: Soft white and club wheat are well suited for making certain baked products such as cakes, cookies, and pastries, and batters such as tempura. Sponge cake quality is an essential end-use trait for U.S. Pacific Northwest soft white wheat, primarily measured by the volume of a cake. The baking of each cake is relatively expensive, labor intensive, and requires a substantial amount of flour. As a result, sponge cake baking is conducted in later generations on a limited number of breeding lines in turn limiting the available options for progression in the breeding program. Insight into the genetic architecture of sponge cake volume would help provide an alternative to cake baking. This knowledge would aid the development of markers to select germplasm with superior and consistent sponge cake quality earlier in the breeding program. In this regard, a genome-wide association study offers a great opportunity to dissect the genetic basis of sponge cake volume and detect associations between markers and causal traits. Few studies have investigated the genetics of sponge cake and to our knowledge no genome-wide association study has been performed to identify genomic regions of association. Here we describe the analysis of 387 wheat genotypes spanning 27 crop years with a total of 685 environments for sponge cake volume. Genotyping by sequencing was used to generate molecular markers in wheat representing germplasm of the PNW. A genome wide association study was conducted to discover marker trait associations, while accounting for population structure and kinship. A total of eight marker trait associations were identified on chromosomes 1AB, 2A, 3BD, 4A, and 6A. Collectively these marker trait associations explained 29.9% of the sponge cake volume variation. The marker trait associations identified explained small proportions of the phenotypic variation meaning that they influenced the wheat’s sponge cake volume minimally individually. Collectively, however, the MTA explained 56% of the heritable variation. The identified marker trait associations should be validated. Once validated, these markers would be valuable incorporations into breeders’ selection criteria pipeline for earlier detection of acceptable sponge cake volume. This study serves as a foundation experiment by providing insights into the genetic architecture of sponge cake volume in an historical dataset. Insight into the genetic architecture of sponge cake volume will help to augment direct phenotyping by providing an alternative to cake baking and earlier detection of suitable breeding lines.