Abstract
Sphingolipids are not only essential structural components of cellular membranes but also key signaling molecules that regulate plant growth, development, and stress responses. However, their specific roles in root development remain largely unknown. In the presented study, we demonstrate that overexpression of the GhGCS1 gene significantly enhances lateral root development in cotton. Integrated comprehensive transcriptome analysis and phytohormone quantification revealed that GhGCS1 promotes lateral root initiation and elongation primarily by suppressing cytokinin biosynthesis. Notably, GhGCS1 overexpression also markedly improved cotton resistance to Verticillium dahliae. Further molecular analyses indicated that GhGCS1 enhances cotton verticillium wilt resistance through modulation of the expression of sphingolipid-associated brassinosteroid- and pathogenesis-related genes. Collectively, these findings reveal a dual regulatory role for GhGCS1 in coordinating root architecture and immune responses in cotton, providing novel insights and potential strategies for developing crop varieties with improved yield potential and stress tolerance.