GhTPS11, underlying an early-maturity QTL cluster on Chr. D08, positively regulates flowering through the age pathway...

We identified GhTPS11 as a positive regulator of flowering in cotton through integrating QTL mapping, transcriptomic analysis and functional assays. Early maturity is one of the most essential targets in cotton breeding improvement. Enhancing early maturity can facilitate cotton rotation, thereby increasing the multiple cropping index and land use efficiency. The early-maturity trait is closely associated with key agronomic characteristics such as flowering time (FT) and plant height (PH). In this study, we identified 11 QTLs for FT and PH, including a QTL cluster on chromosome D08 (Chr. D08), using a recombinant inbred line (RIL) population derived from a cross between the early-maturing cultivar LMY19 and the late-maturing cultivar LMY37. Through integrated analysis of transcriptome data and DNA sequence variation, GhTPS11 (trehalose-6-phosphate synthase 11) was identified as a key candidate gene. Heterologous expression of GhTPS11 in Arabidopsis resulted in significantly earlier bolting in transgenic lines compared to the wild type (WT). Conversely, silencing GhTPS11 in cotton via virus-induced gene silencing (VIGS) delayed both squaring and flowering, indicating that GhTPS11 acts as a positive regulator of flowering in cotton. RNA-seq analysis suggested that GhTPS11 integrates carbon metabolism with the age pathway via trehalose-6-phosphate (Tre6P) signaling to control flowering. In summary, this study identifies a causal gene underlying an early-maturity QTL cluster, elucidates its function, and provides a valuable genetic resource and theoretical foundation for molecular breeding in cotton.