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ARS Home » Plains Area » El Reno, Oklahoma » Oklahoma and Central Plains Agricultural Research Center » Peanut and Small Grains Research Unit » Research » Publications at this Location » Publication #396959
Research Project: Genetic Mechanisms and Improvement of Insect Resistance in Wheat, Barley, and Sorghum

Location: Peanut and Small Grains Research Unit

Title: Genomic location of Gb1, a unique gene conferring wheat resistance to greenbug biotype F

Author
item Xu, Xiangyang
item Li, Genqiao
item Bai, Guihua
item CARVER, BRETT - Oklahoma State University
item BIAN, RUOLIN - Kansas State University
item Bernardo, Amy
item Armstrong, John

Submitted to: The Crop Journal
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 2/6/2023
Publication Date: 2/23/2023
Citation: Xu, X., Li, G., Bai, G., Carver, B.F., Bian, R., Bernardo, A.E., Armstrong, J.S. 2023. Genomic location of Gb1, a unique gene conferring wheat resistance to greenbug biotype F. The Crop Journal. https://doi.org/10.1016/j.cj.2023.02.002.
DOI: https://doi.org/10.1016/j.cj.2023.02.002

Interpretive Summary: Greenbug (Schizaphis graminum, Rondani) is a serious insect pest in many wheat growing regions, and has been infestating cereal crops in the USA for over a century. Continuous occurrence of new greenbug biotypes makes it essential to explore all greenbug resistant sources available to manage this pest. Gb1, a recessive greenbug resistance gene in DS28A, confers resistance to several economically important greenbug biotypes and is the only gene found to be resistant to the greenbug biotype F. A set of 174 F2:3 lines from the cross DS28A × Custer was evaluated for resistance to greenbug biotype F in 2020 and 2022, and genotyped using SSR markers and kompetitive allele specific PCR (KASP) markers. Genetic analysis located Gb1 to the terminal region of the short arm of chromosome 1A. The Gb1 location was confirmed in a second population derived from the cross DS28A × PI 697274. The combined data analysis from the two mapping populations delimited Gb1 to a <1 Mb interval on 1AS. The KASP markers developed in this study have the potential to tag Gb1 in marker-assisted selection.

Technical Abstract: Greenbug (Schizaphis graminum, Rondani) is a serious inset pest in many wheat growing regions, and has been inflicting cereal crops in the USA for over a century. Continuous occurrence of new greenbug biotypes makes it essential to explore all greenbug resistant sources available to manage this pest. Gb1, a recessive greenbug resistance gene in DS28A, confers resistance to several economically important greenbug biotypes and is the only gene found to be resistant to the greenbug biotype F. A set of 174 F2:3 lines from the cross DS28A × Custer was evaluated for resistance to greenbug biotype F in 2020 and 2022. The selective genotyping of the corresponding F2 population using single nucleotide polymorphism (SNP) markers generated by genotyping-by-sequencing (GBS) led to the identification of two candidate genomic regions for Gb1. Thus SSR markers previously mapped in these regions were used to genotype the F2 population, and linkage analysis indicted that Gb1 resides on the short arm of chromosome 1A. Kompetitive allele specific PCR (KASP) markers were developed from the selected SNPs in the target region to genotype the F2 population, and Gb1 was placed to the terminal region of 1AS. The Gb1 location was confirmed in a second population derived from the cross DS28A × PI 697274. The combined data analysis from the two mapping populations delimited Gb1 to a <1 Mb interval between 13,328,200 and 14,241,426 bp on 1AS, where 22 high confidence genes were annotated including four RGA5 genes.