Season-specific cutting strategies enable efficient clonal propagation of Berberis amurensis Rupr

Berberis amurensis Rupr. is a pollinator-supporting shrub valued for its medicinal and ornamental traits; however, practical propagation is limited due to slow seed germination and a lack of vegetative propagation methods. This study investigated the impact of cutting season, auxin concentration, and cutting type on the adventitious rooting of stem cuttings. Hardwood cutting rooted in May showed higher survival, rooting percentage, and root system development than those rooted in August, and potassium indole-3-butyric acid at 500–1000 mg L−1 increased root biomass and root number in May. In August, greenwood cuttings rooted and survived better than hardwood cuttings, even without auxin treatment. Anatomical observations confirmed that the adventitious root originated from the cambial zone and reconnected with the stem vascular tissues. These findings establish simple and season-specific protocols for the clonal propagation of B. amurensis for ex situ conservation and horticultural use.