Research Strigolactones optimise plant water usage by modulating vessel formation

Wood formation supports plant growth by enabling water and nutrient transport through vessel elements derived from cambium stem cells (CSCs). CSCs generate vascular tissues supporting long-distance transport in plants, but how the fate of CSC derivatives is regulated has been unclear. Using single-cell transcriptomics in Arabidopsis thaliana, the Greb lab showed that the strigolactone (SL) signalling pathway inhibits vessel element formation in response to limited water availability. SL signalling is generally active in differentiating vascular tissues but remains low in CSCs and developing vessels, where it influences cell fate and drought response. Changes in vessel formation driven by SL affect transpiration rates, highlighting how structural alignments of vascular tissues impacts water balance and drought resistance.