|Jampatong, C - UNIV OF MISSOURI-COLUMBIA|
|Barry, B - RETIRED - USDA/ARS|
|Byrne, P - COLORADO STATE UNIVERSITY|
|Kross, H - UNIV OF MISSOURI-COLUMBIA|
Submitted to: Crop Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: June 29, 2001
Publication Date: January 1, 2002
Citation: Jampatong, C., Mcmullen, M.D., Barry, B.D., Darrah, L.L., Byrne, P.F., Kross, H. 2002. Quantitative trait loci for first- and second-generation european corn borer resistance in the maize inbred mo47. Crop Science. V.41:1066-1072. Interpretive Summary: The European corn borer (ECB), is a serious insect pest of corn in the United States. Losses to farmers resulting from ECB damage and control costs exceed $1 billion each year. There are two distinct generations of ECB each year in the US Corn Belt. The most efficient and environmentally friendly method of controlling ECB would be to develop resistant varieties of corn. Corn inbred line Mo47 was developed to be resistant to both generations of ECB. Mo47 differs from other resistant corn in being derived from tropical germplasm, therefore extending the options available to corn breeders in selecting for resistance. To assist in using Mo47 as a source of resistance to ECB, we identified the genomic regions of Mo47 that confer resistance to each generation of ECB. Our findings impact corn breeders by providing the scientific basis for selecting resistance to ECB by using molecular genetic approaches. Our research also promotes farm-level sustainability of corn production by promoting use of novel resistance sources for ECB resistance.
Technical Abstract: European corn borer (ECB), Ostrinia nubilalis (Hubner), family Crambidae, order Lepidoptera, is a serious insect pest of maize (Zea mays L.) in the United States. An understanding of the genetic basis for ECB resistance should increase the efficiency of breeding insect-resistant germplasm. The objectives of this study were to determine the number, genomic positions, and genetic effects of quantitative trait loci conferring resistance to first- (1ECB) and second-generation (2ECB) ECB. The study included 244 F2:3 families derived from the cross of B73 (susceptible) x Mo47 (resistant). Inbred Mo47 represented a novel source of ECB resistance containing 50% tropical germplasm. Quantitative trait loci (QTL) analyses for three individual environments and combined across environments were performed by composite interval mapping using QTL Cartographer. In the combined analysis, for first-generation ECB leaf feeding, nine QTLs were identified on chromosomes 1(three QTLs), 2, 4 (two QTLs), 5, 6, and 8 Seven QTLs for resistance to second-generation ECB tunnel length were found on chromosomes 2, 5 (two QTLs), 6 (two QTLs), 8, and 9. Many of the QTLs detected are located in genomic regions reported for resistance to other stem borer pests of maize. However, inconsistency of QTLs across environments complicates use of Mo47 for marker-assisted selection of ECB resistance.