Caulogenesis refers to formation of:
Caulogenesis is specific morphogenic pathway leading to shoot formation in vitro, term derived from caulis meaning stem. As branch of organogenesis it requires high cytokinin to low auxin ratio that suppresses root program and promotes shoot identity. At cellular level cytokinins like BAP, kinetin, zeatin bind histidine kinase receptors AHK2/3/4 initiating phosphorelay through AHP proteins to activate type-B Arabidopsis Response Regulators ARR1, ARR10, ARR12. These upregulate WUSCHEL organizing center, SHOOT MERISTEMLESS STM and CLAVATA3 feedback maintaining stem cell pool while inducing CYCD3
Ref: Hartmann & Kester Plant Propagation, Chap. 17; Taiz & Zeiger Physiology, Chap. 21 cytokinin signaling.