Ou_2025_Mol.Plant__

Strigolactones (SLs) are carotenoid-derived phytohormones that regulate plant development and mediate rhizosphere interactions. Synthesized from beta-carotene through a multistep enzymatic pathway, SLs modulate key physiological processes, including shoot branching, leaf development, flowering, and root growth. Beyond their endogenous roles, SLs are exuded into the soil, where they serve as ecological signals. The exuded SLs facilitate symbiotic relationships with arbuscular mycorrhizal fungi (AMF) for nutrient exchange, while also are exploited by parasitic weeds to locate host plants. Although the core SL biosynthesis and signaling pathways have been elucidated, emerging research continues to uncover new layers of complexity in their regulation and function. Here, we present a comprehensive overview of SLs, summarizing and updating current knowledge and recent advances in their biosynthesis, transport, perception and signal transduction, along with their multifaceted functions. Moreover, we discuss the challenges currently faced in SL research and identify urgent questions for future investigation. Addressing these issues would further enhance our understanding of the SL pathway and promote its application in agriculture.