QUANTITATIVE TRAIT LOCI FOR FIRST- AND SECOND-GENERATION EUROPEAN CORN BORER RESISTANCE DERIVED FROM THE MAIZE INBRED Mo47

QUANTITATIVE TRAIT LOCI FOR FIRST- AND SECOND-GENERATION EUROPEAN CORN BORER RESISTANCE DERIVED FROM THE MAIZE INBRED Mo47.

Chaba Jampatong, Michael D. McMullen*, B. Dean Barry, Larry L. Darrah, Patrick F. Byrne, and Heike Kross

C. Jampatong, Department of Agronomy, University of Missouri, Columbia, MO 65211 (current address, National Corn and Sorghum Research Center, Kasetsart University, Klangdong, Pakchong, Nakhonratchasima,Thailand); M.D. McMullen and L.L. Darrah, USDA-ARS, Plant Genetics Research Unit and Department of Agronomy, University of Missouri, Columbia, MO 65211; B.D. Barry, USDA-ARS, Plant Genetics Research Unit (retired) and Department of Entomology, University of Missouri, Columbia, MO 65211; P.F. Byrne, Department of Soil and Crop Sciences, Colorado State University, Ft. Collins, CO 80523; and H. Kross, Department of Agronomy, University of Missouri, Columbia, MO 65211.

Received _______. *Corresponding Author (mcmullenm@missouri.edu).

Abbreviations: ARC, Agronomy Research Center; CIM, composite interval mapping; ECB, European corn borer; 1ECB, leaf feeding damage from first-generation European corn borer; 2ECB, stalk tunneling damage from second-generation European corn borer; DIMBOA, 2,4-dihydroxy-7-methoxy-2H-1,4-benzoxazin-3(4H)-(one); GP, Grand Pass; HB, Hinkson Bottoms: LOD, log₁₀ of the likelihood odds ratio: MAS, marker assisted selection: QTL, quantitative trait locus; RFLP, restriction fragment length polymorphism; RIL, recombinant inbred line; SCB, sugarcane borer; SSR, simple sequence repeat: SWCB, southwestern corn borer; UMC, University of Missouri-Columbia.

ABSTRACT

European corn borer (ECB), Ostrinia nubilalis (Hübner), family Crambidae, order Lepidoptera, is a serious insect pest of maize (Zea mays L.) in the United States. Understanding 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 (QTL) conferring resistance to leaf feeding damage cause by first-generation ECB (1ECB, defined as the trait of leaf feeding damage) and stalk tunnelling caused by second-generation ECB (2ECB, defined as the trait of stalk tunnel damage). The study included 244 F_2:3 families derived from the cross of B73Ht (susceptible) × Mo47 (resistant). Inbred Mo47 represented a novel source of ECB resistance containing 50% tropical germplasm. The QTL analyses for three individual environments and combined across environments were performed by composite interval mapping using QTL Cartographer. Nine QTLs were identified for 1ECB on chromosomes 1 (three QTLs), 2, 4 (two QTLs), 5, 6, and 8, based on data combined across environments. Seven QTLs for 2ECB were found on chromosomes 2, 5 (two QTLs), 6 (two QTLs), 8, and 9. Several of the QTLs detected are located in genomic regions reported for resistance to other stem borer pests of maize. Inconsistency of QTLs across environments complicates use of Mo47 for marker-assisted selection of ECB resistance.