Author
JUN, TAE-HWAN - The Ohio State University | |
Mian, Rouf | |
MICHEL, ANDREW - The Ohio State University |
Submitted to: Heredity
Publication Type: Peer Reviewed Journal Publication Acceptance Date: 2/15/2013 Publication Date: 3/13/2013 Citation: Jun, T., Mian, R.M., Michel, A.P. 2013. Genetic mapping of three quantitative trait loci for soybean aphid resistance in PI 567324. Heredity. 111:16-22. DOI:10.1038/hdy.2013.10. Interpretive Summary: The soybean aphid is the most damaging insect pest of soybean in North America. Recently, resistant soybean lines have been discovered and at least four aphid resistance genes (Rag1, Rag2, Rag3, and rag4) have been mapped on different soybean chromosomes with DNA markers. However, the discovery of new soybean aphid biotypes capable of defeating soybean resistance conferred by most single gene indicates the need for finding sources with multi-genic resistance to the aphid. This study was conducted for mapping of multi-genic or quantitative trait loci (QTL) for aphid resistance in PI 567324. We identified two major QTL for aphid resistance on soybean chromosome 13 using 184 recombinant inbred lines (RILs) from a ‘Wyandot’ x PI 567324 cross. In reference to previous studies, the QTL_13_1 was located close to the Rag2 gene, and the QTL_13_2 was close to the rag4 gene. A minor QTL (QTL_6_1) was also detected on chromosome 6, where no gene for soybean aphid resistance has been reported so far. These results indicate that PI 567324 possesses multi-genic resistance to the soybean aphid. The DNA markers closely linked to the QTL reported here will be useful for development of cultivars with multi-genic resistance to soybean aphids. Cultivars with multi-geneic resistance are expected to provide more durable resistance against different soybean aphid biotypes compared to cultivars with single gene for aphid resistance. Technical Abstract: Host-plant resistance is an effective method for controlling soybean aphid (Aphis glycines Matsumura), the most damaging insect pest of soybean [Glycine max (L.) Merr.] in North America. Recently, resistant soybean lines have been discovered and at least four aphid resistance genes (Rag1, Rag2, Rag3, and rag4) have been mapped on different soybean chromosomes. However, the evolution of new soybean aphid biotypes capable of defeating host-plant resistance conferred by most single gene (R-gene) indicates the need for finding sources with multigenic resistance to the aphid. This study was conducted for mapping of quantitative trait loci (QTL) for aphid resistance in PI 567324. We identified two major QTL (QTL_13_1 and QTL_13_2) for aphid resistance on soybean chromosome 13 using 184 recombinant inbred lines (RILs) from a ‘Wyandot’ x PI 567324 cross. In reference to previous studies, the QTL_13_1 was located close to the Rag2 gene, and the QTL_13_2 was close to the rag4 gene. A minor QTL (QTL_6_1) was also detected on chromosome 6, where no gene for soybean aphid resistance has been reported so far. These results indicate that PI 567324 possesses multigenic resistance to the soybean aphid. The molecular markers closely linked to the QTL reported here will be useful for development of cultivars with multigenic resistance to soybean aphids. Cultivars with multigeneic resistance are expected to provide broader and more durable resistance against soybean aphids compared to cultivars with single gene for aphid resistance. |