玉米抗茎腐病主效新位点qRfg3.03的遗传定位OA

Maize stalk rot is a destructive disease prevalent across major corn production regions in China,posing a significant threat to both yield and grain quality.Therefore,the identification of elite germplasm and underlying gene resources for stalk rot resistance are of great significance.In this study,an elite maize inbred line CNH3323,previously screened for high resistance to maize stalk rot via large-scale germplasm accurate phenotyping,was used as the resistant parent to construct two segregating populations,including 280 F2∶3 families and 410 doubled haploid(DH)homozygous lines,respectively.The phenotypic evaluations for stalk rot resistance were conducted for two segregating populations under both natural infection and artificial inoculation conditions across two locations.Based on the genotyping of segregating populations and the construction of linkage maps,QTL mapping for maize stalk rot resistance was performed.The results showed that a total of 24 QTLs associated with stalk rot resistance were detected across different environments,distributed on eight chromosomes except for chromosomes 5 and 8.Notably,an environment stable QTL with major-effect,designated as qRfg3.03,was consistently mapped to the bin3.03 region on chromosome 3 using different populations,which explained up to 30.36％of the phenotypic variance.This study provides important candidate loci for the genetic dissection of maize stalk rot resistance and also offers valuable gene resources for maize improvement and the breeding for resistance to stalk rot,which holds significant theoretical research and practical application value.