Identification of Candidate Genes Controlling Resistance to <i>Verticillium dahliae</i> Using CCRI70 Recombinant Inbred Line Population in <i>Gossypium hirsutum</i>

Verticillium wilt (VW) severely limits the cotton yield and fiber quality. Marker-assisted selection is an efficient strategy for breeding resistant varieties. In this study, a high-density genetic map was constructed by using an F8:9 recombinant inbred line (RIL) population derived from CCRI70. Phenotypic data on disease incidence (DINC) and disease index (DI) were collected across six environments. A total of 59 QTLs for DINC and 60 QTLs for DI were identified, with three and six stable across multiple environments, respectively. These QTLs formed 18 clusters across 13 chromosomes, showing consistent additive effects. Transcriptome analysis revealed eight differentially expressed candidate genes within stable QTL regions. Among them, <i>GH_D</i><i>05</i><i>G</i><i>1495</i>, <i>GH</i>_<i>A</i><i>09</i><i>G</i><i>1013</i>, and <i>GH_D</i><i>05</i><i>G</i><i>1683</i> were further validated by virus-induced gene silencing as key genes conferring <i>V. dahliae</i> resistance in cotton. This study provides valuable genetic resources for improving Verticillium wilt resistance in cotton breeding.