Control of shoot branching involves auxin, cytokinin and strigolactones, the most recent discovered plant hormone which inhibits axillary bud outgrowth.In pea, most of the high branching ramosus (rms) mutants show high expression of the strigolactone-biosynthesis RMS1/CCD8 gene and low xylem-sap cytokinin content.In contrast, the high branching rms2 mutant has opposite phenotype with very low expression of RMS1 and high xylem-sap cytokinin content.Physiological characterization of the pea rms2 mutant by hormone quantifications and grafting experiments suggested that rms2 was affected in a shoot-to-root feedback signal controlling both strigolactones biosynthesis and cytokinin level in the xylem sap independently from auxin.