Excising Part of Primary Root Induces Adventitious Lateral Root (adLR) Formation in Peach Seedlings: An Approach to Dissect adLR Origin

Peach (Prunus persica L.) trees exhibit low propagation efficiency from cuttings, primarily due to the limited ability of their cuttings to develop adventitious roots (ARs). ARs originate from a single or a few cells and occur randomly and in varying numbers at the base of the cuttings. This poses a challenge for precise research on their regulatory mechanisms. Adventitious lateral roots (adLRs) are one kind of AR, which are induced from injured primary roots. In this study, we developed a method to induce adLRs by removing part of the primary root of young peach seedlings. The adLRs induced by this method are characterized by no obvious callus formation, a relatively stable number (2–4 roots), a fixed occurrence position (at the incision site), and a rooting rate of 100%. Using this system, we conducted transcriptome sequencing analysis during the early stage of adLR induction (0–24 h). The results showed that after the primary root was removed, the jasmonic acid (JA), wound, ethylene (ET), auxin, and salicylic acid (SA) signaling pathways were rapidly activated; subsequently, pathways related to root formation and development were significantly enriched. By screening early rapid-response genes, we successfully identified two key genes, PpF-box and PpERF13, that are involved in AR formation in peach. This study not only provides a reliable and efficient research system for analyzing the molecular regulatory mechanism of AR formation in peach, but also lays an important foundation for future in-depth studies using precise technologies such as single-cell sequencing and microscopic sampling.