Local Cytokinin (Ck) Biosynthesis and Zeatin-Type CKs are Controlling Rose Axillary Bud Growth

Introduction Shootand root meristems produce phytohormones, co-ordinate morphogenic processes via hormone gradients, and integrate signals from other organs. Cytokinins (CKs) regulate e.g. root and shoot growth and CK levels are infl uenced by environmental factors. Auxin suppresses onset of axillary bud growth, which is promoted by CKs, but it has not been demonstrated unequivocally that root-derived CKs trigger release of axillary buds. Axillary bud growth may be mediated by altered metabolism of CKs in green plantparts, in addition to synthesis in roots.