Cutting propagation is a commonly employed technology for vegetative reproduction in agricultural, forestry, and horticultural practice. The success of cutting propagation depends on adventitious root (AR) formation—a process whereby roots regenerate from stem cuttings or leaf cuttings. In this review, we summarize the distinct stages of cutting-induced AR formation and highlight the pivotal roles of plant hormones and age in this process. Jasmonic acid (JA) acts as a master trigger for promoting AR formation, while auxin serves as the core regulator, driving AR formation. Furthermore, plant age is a crucial factor determining the regenerative competence of cuttings. Notably, age and JA collaboratively modulate auxin synthesis in cutting-induced AR formation. Overall, this review not only elucidates the molecular mechanisms underlying AR formation but also provides valuable insights for improving efficiency of cutting propagation in various plant species.

De novo root regeneration is the process by which adventitious roots form around the wound site from wounded or detached plant organs. The de novo root regeneration process has been widely exploited in cutting technology used for vegetative propagation. Here, we employed detached leaf explants from Arabidopsis thaliana to form adventitious roots for studying the process of de novo root regeneration. GUS staining showed that the expression of CLAVATA3/EMBRYO SURROUNDING REGION-RELATED26(CLE26) was gradually increased surrounding the wound site of leaf explants during adventitious root formation. Semi-thin sections further showed that the expression pattern of CLE26 was closely linked to the formation of adventitious roots. Next, genetic analyses confirmed that the CLE26 gene was involved in de novo root regeneration. Furthermore, RNA sequencing (RNA-seq) of the leaf explants revealed that stress-related genes might be involved in CLE26-mediated adventitious root formation. Specifically, genes associated with the hydrogen peroxide catabolic process and oxidative stress response were predominantly upregulated in the cle26 mutant. In contrast, genes involved in the response to salicylic acid were largely downregulated in the cle26 mutant. Overall, our study indicates that the mutation in CLE26 might upregulate the expression of genes involved in reactive oxygen species metabolism or suppress the expression of genes associated with salicylic acid synthesis, thus promoting the formation of adventitious roots. These findings suggest that CLE26 is a potential candidate for the genetic improvement of adventitious rooting in cuttings.