Soybean genes for resistance to Aphis glycines
Inventors
Hill, Curtis B. • Hartman, Glen L. • Li, Yan • Diers, Brian • Carlson, Shawn
Assignees
US Department of Agriculture USDA • University of Illinois System
Publication Number
US-8680364-B2
Publication Date
2014-03-25
Expiration Date
2025-06-21
Interested in licensing this patent?
MTEC can help explore whether this patent might be available for licensing for your application.
Abstract
Aphis glycines resistance (RAG) genes are provided by this invention, along with methods for identifying their presence using marker-assisted selection. Varieties of G. max and G. soja having resistance to A. glycines have been identified. The RAG genes, as well as the methods, aphid-resistant varieties, and markers disclosed herein may be used to breed new elite lines expressing soybean aphid resistance.
Core Innovation
This invention provides soybean genes for resistance to the soybean aphid, Aphis glycines, designated as Rag1 genes, which map to a novel chromosomal locus on linkage group M. Methods for identifying the presence of these genes through marker-assisted selection using molecular markers closely linked to the resistance gene, especially SSR markers Satt435 and Satt463, are described. The invention includes aphid-resistant varieties, markers, and breeding methods to introgress the resistance trait into elite soybean germplasm.
The problem being solved is the severe damage and yield losses caused by Aphis glycines, a recently introduced pest in North America, which reduces soybean production through feeding damage and virus transmission. Conventional control methods, including insecticides, are limited and integrating plant resistance is recognized as a critical and cost-effective management strategy. Prior to this invention, resistance had been reported only in wild soybeans and not in cultivated G. max varieties, and molecular tools for breeding aphid resistance into elite soybeans were lacking.
The invention addresses the need for methods and molecular tools that allow reliable and predictable introgression of Aphis glycines resistance into high-yielding Glycine max varieties. This includes using closely linked molecular markers flanking the resistance locus for marker-assisted selection and breeding. Resistant germplasm sources such as Dowling and Jackson, which carry the Rag1 resistance gene, are identified and leveraged to develop soybean lines that are resistant to Aphis glycines while maintaining desirable agronomic traits.
Claims Coverage
The patent contains one independent method claim and several dependent claims detailing specific aspects of the method and germplasm used. The main inventive features cover the application of molecular markers linked to the Rag1 gene for marker-assisted selection and the breeding method for introgressing aphid resistance.
Method for marker-assisted introgression of Aphis glycines resistance
A method for reliably and predictably introgressing soybean aphid (Aphis glycines) resistance into non-resistant or less resistant soybean germplasm by crossing resistant and susceptible varieties, followed by marker-assisted selection of progeny containing a resistance gene (RAG) locus mapped to linkage group M and flanked by SSR markers Satt435 and Satt463.
Use of flanking SSR markers for detection of resistance gene
Detection of the presence or absence of the RAG resistance gene by analyzing PCR-amplified polymorphic marker fragments corresponding in size to fragments from known resistant varieties Dowling and Jackson, using markers Satt435, Satt463, or Satt245 or markers mapping within 20 cM of these markers.
Inclusion of specific resistant soybean germplasm as sources of RAG resistance
The use of soybean germplasm varieties with specific Plant Introduction (PI) numbers, including but not limited to 548445 (CNS), 548663 (Dowling), 548657 (Jackson), and 548480 (Palmetto), as donors of aphid resistance in breeding methods.
Production of inbred soybean cultivars homozygous for aphid resistance
A breeding method involving crossing a donor parental line carrying the RAG gene with a high-yielding susceptible line to produce segregating populations, followed by marker-assisted selection and selfing to obtain homozygous inbred lines that confer aphid resistance in hybrid combinations.
The claims cover a method of marker-assisted breeding utilizing molecular markers linked to the Rag1 aphid resistance gene on linkage group M for identifying and introgressing resistance into soybean germplasm, including specific soybean varieties as sources, and the development of homozygous resistant inbred lines.
Stated Advantages
Enables reliable and predictable introgression of aphid resistance into elite soybean germplasm using molecular markers.
Facilitates marker-assisted selection that reduces time and effort compared to phenotypic screening by live aphid bioassay.
Allows the development of soybean lines conferring resistance to Aphis glycines in hybrid combinations while maintaining desirable agronomic traits.
Documented Applications
Breeding of new elite Glycine max soybean lines expressing resistance to the soybean aphid Aphis glycines.
Use of marker-assisted selection techniques to identify and introgress the Rag1 gene conferring aphid resistance.
Use of specific soybean varieties and their progeny as sources of aphid resistance in breeding programs.
Interested in licensing this patent?