Abstract
Intermediate wheatgrass [Thinopyrum intermedium (Host) Barkworth & D.R. Dewey] (IWG) is a perennial, cool-season grass species currently undergoing direct domestication as one of the first perennial grain crops. To domesticate and improve this obligately outcrossing allohexaploid (2n = 6x = 42), breeders are using both phenotypic- and genomic-assisted recurrent selection methodologies. Thus far, efforts have focused primarily on improving domestication traits and yield, but breeders are limited by the relatively narrow understanding of the genetic control of these traits. An IWG nested association mapping (NAM) population with 1,168 F1 progeny from 10 families was grown in four unique growing environments (St. Paul, MN, and Salina, KS, in 2017 and 2018) and evaluated for a series of 11 yield-component traits. Using a population-specific genetic map and 8,003 single-nucleotide polymorphism (SNP) markers, we used both linkage mapping (LM) and genome-wide association study (GWAS) to dissect the genetic control of a series of yield-component traits. We identified 20 significant markers in GWAS and 28 in LM that were detected in at least two environments, several of which were shared across traits. The QTL regions on chromosomes 5 and 9 were significant for eight of 11 traits, and many were detected across multiple analysis methods. The results described herein provide additional resources for incorporating QTL as fixed effects in routine genomic selection pipelines to expedite the gains from selection for yield in this new perennial grain crop.
| Original language | English (US) |
|---|---|
| Pages (from-to) | 880-892 |
| Number of pages | 13 |
| Journal | Crop Science |
| Volume | 62 |
| Issue number | 2 |
| DOIs | |
| State | Published - Mar 1 2022 |
Bibliographical note
Funding Information:This work was supported by the Perennial Agriculture Project in conjunction with the Malone Family Land Preservation Foundation and The Land Institute. We thank Dr. Steven R. Larson for assistance with linkage mapping analyses, Xiaofei Zhang for obtaining the funding for the project and helping to create the NAM population, and Prabin Bajgain for assistance in developing sequencing libraries. Thank you to Brett Heim and Marty Christians for their contributions to data collection and field maintenance. We acknowledge the following individuals for their help in collecting data: Andressa Spuri Azarias, Arthur Martins, Oswaldo Birungi, Caroline Elmer, Phoebe Wanjira, Mario Fagundes, Jennifer LaValley, Charlotte Bonner, and Ellen Goedtke. Finally, we thank the Land Institute Interns of 2017 and 2018 for assistance in the field during data collection trips and harvesting. Mention of trade names or commercial products in this publication is solely for the purpose of providing specific information and does not imply recommendation or endorsement by the USDA. USDA is an equal opportunity provider and employer.
Funding Information:
This work was supported by the Perennial Agriculture Project in conjunction with the Malone Family Land Preservation Foundation and The Land Institute. We thank Dr. Steven R. Larson for assistance with linkage mapping analyses, Xiaofei Zhang for obtaining the funding for the project and helping to create the NAM population, and Prabin Bajgain for assistance in developing sequencing libraries. Thank you to Brett Heim and Marty Christians for their contributions to data collection and field maintenance. We acknowledge the following individuals for their help in collecting data: Andressa Spuri Azarias, Arthur Martins, Oswaldo Birungi, Caroline Elmer, Phoebe Wanjira, Mario Fagundes, Jennifer LaValley, Charlotte Bonner, and Ellen Goedtke. Finally, we thank the Land Institute Interns of 2017 and 2018 for assistance in the field during data collection trips and harvesting.
Publisher Copyright:
© 2022 The Authors. Crop Science published by Wiley Periodicals LLC on behalf of Crop Science Society of America
