QTL mapping for resistance against the European corn borer (Ostrinia nubilalis H.) in early maturing European dent germplasm

European corn borer (ECB, Ostrinia nubilalis Hubner) is a major pest of mai ze in Central Europe. We mapped and characterized quantitative trait loci ( QTLs) involved in resistance of maize against ECB damage, compared them wit h QTLs for agronomic traits, and evaluated the usefulness of marker-assiste d selection (MAS) for improving ECB resistance in early maturing European m aize,germplasm. A total 226 F-3 families from the cross D06 (resistant) x D 408 (susceptible), together with 93 RFLP and two SSR markers were used for the QTL analyses. For each F-3 family we measured the length of tunnels pro duced by larval stalk mining (TL), stalk damage ratings (SDR), and relative grain yield (RGY) in field experiments, with two replications in two envir onments in 1 year. The agronomic traits comprised grain yield under insecti cide protection (GYP) and manual ECB larval infestation (GYI), the date of anthesis (ANT), and the in vitro digestibility of organic matter (IVDOM) of stover. Estimates of genotypic variance (sigma (2)(g)) were highly signifi cant for all traits. Six QTLs for TL and five QTLs for SDR were detected, e xplaining about 50.0% of sigma (2)(g). Most QTLs showed additive gene actio n for TL and dominance for SDR. No QTL was found for RGY. The number of QTL s detected for the agronomic traits ranged from two for GYI to 12 for ANT, explaining 12.5 to 57.3% of sigma (2)(g), respectively. Only a single QTL w as in common between the two resistance traits, as expected from the modera te trait correlation and the moderate proportions of sigma (2)(g) explained . Based on these results, MAS for improving ECB resistance can be competiti ve when cost-effective PCR-based marker systems are applied. However, it re mains to be established whether the putative QTL regions for ECB resistance detected in the population D06 x D408 are consistent across other early ma turing European maize germplasms.