Rhizospheric functions and potential applications of strigolactones

The rhizosphere represents a dynamic biochemical interface where metabolic signals orchestrate the interplay among plants, microbiota, and the edaphic environment. Strigolactone, a class of carotenoid-derived phytohormones, is central to this belowground communication network. This review synthesises the multifaceted roles of strigolactones in the rhizosphere, detailing how it coordinates a spectrum of ecological interactions, from parasitic weed germination and kin recognition among neighbouring plants to symbiotic partnerships with arbuscular mycorrhizal fungi and nitrogen-fixing rhizobia. We further examine the molecular logic underpinning strigolactone-mediated responses to multi-nutrient stresses, including nitrogen, phosphorus, sulphur, iron, and zinc deficiencies, as well as heavy metal toxicities. We also discuss how the expanding structural repertoire of canonical and non-canonical strigolactones enables a nuanced functional split between endogenous hormonal regulation and rhizospheric signalling. Finally, we assess the translational potential of strigolactones for sustainable agriculture, specifically in optimising crop architecture, deploying "suicidal germination" strategies, and engineering beneficial microbial communities, while identifying critical research gaps concerning structure-specific perception, ABC-transporter mediated exudation, and nutrient-signalling crosstalk. • Strigolactones (SLs) mediate rhizosphere interactions and nutrient signalling. • SLs mediate plant adaptation to nutrient stress, enhancing phosphate acquisition. • Manipulating SL pathways improves crop resistance to parasitic weeds. • SL chemical diversity offers novel targets for sustainable pest management.