Location: Peanut and Small Grains Research Unit
Project Number: 3070-21000-009-000-D
Project Type: In-House Appropriated
Start Date: Mar 1, 2018
End Date: Feb 28, 2023
Objective 1: Identify new germplasm sources of resistance to cereal aphids, including greenbugs, Russian wheat aphid, bird cherry-oat aphid, and other important insect pests, in wheat, barley, and sorghum. Subobjective 1A. Evaluate available germplasm resources (U.S. germplasm collections and accessible exotic resources) to identify new sources resistant to insect pests [Russian wheat aphid (RWA), greenbug (GB), bird cherry-oat aphid (BCOA)], and other important insect pests in wheat, barley, sorghum, and related species. Objective 2: Characterize the genes controlling pest resistance and other related traits that are important for sustainable cereal crop production. Subobjective 2.A. Develop and evaluate genetic populations to determine the genetic control of host resistance to GB, RWA, and BCOA in barley. Subobjective 2.B. Develop and evaluate genetic populations to determine levels of genetic diversity of host resistance and genes controlling the resistance to GB, RWA, SCA, and BCOA in wheat, barley, and sorghum. Subobjective 2.C. Map genes conferring resistance to cereal aphids, and develop genomic tools for cloning and marker-assisted selection of aphid resistance genes. Subobjective 2.D. Conduct functional genomics studies on host response to attack by GB and sugarcane aphids (SCA), leading to advanced understanding of the defense mechanisms in the hosts and discovery of genes and factors that affect host defense against insect pests (i.e. GB and SCA) in grain sorghum, forage sorghum, and related species. Subobjective 2.E. Reveal the genetic architecture of BCOA resistance using genomewide association study (GWAS), and develop genomic tools to facilitate rapid introgression of aphid resistance genes into adapted germplasm. Objective 3: Develop enhanced germplasm and new varieties of sorghum, wheat, and barley with resistance to insect pests. Subobjective 3.A. Develop high performance wheat, barley, and sorghum germplasm with enhanced resistance to GB, RWA, SCA, or BCOA, and release to the public. Subobjective 3.B. Develop winter malting barley germplasm and cultivars for the Great Plains with enhanced insect resistance.
Wheat, barley and sorghum are the major cereal grains in the United States but their production is often threatened by destructive aphid pests, specifically the Russian wheat aphid, greenbug, bird cherry-oat aphid, and sugarcane aphid. Identification of natural resistance and use of genetically pest-resistant cultivars and hybrids in an integrated pest management program are the most economical and environmentally sound methods to reduce the negative economic impact of these damaging aphids. The overall goal of this project is to develop high performance wheat, barley, and sorghum with resistance to aphid pests. To accomplish this goal, the project will search available germplasm collections to find new, effective sources of resistance to aphid pests that are notorious for overcoming resistance through biotype evolution. The genetic diversity and resistance mechanisms will be analyzed, and resistance genes will be characterized and transferred into adapted genetic backgrounds. Plant genotyping will be conducted to map aphid resistance genes to the crop chromosomes and to develop molecular markers to facilitate marker-assisted selection and map-based gene cloning. The research team of the project will work closely with collaborating plant breeding programs to obtain elite breeding lines to use as parents in backcrossing procedures to transfer aphid resistance and other value-added traits. The genetically improved germplasm and varieties will be field-tested for agronomic and quality performance prior to release. The project will provide testing and selecting support to assure that these desirable genes move through the various breeding programs on their way to producers via improved cultivar and hybrid releases.