Exploration of Molecular Mechanism and Key Factors for the Survival of ‘Yueshenda 10’ Cuttings Under ABT1 Treatment

Mulberry trees are not only economically significant forest trees with substantial added value but also serve as exceptional candidates for environmental management and ecological enhancement. However, in the widely applied cutting propagation of mulberry, the intensity of adventitious root formation in cuttings has long remained a key challenge in the cutting process. Our research group previously found that 800 mg/L Rooting Powder No. 1 (ABT1) has an obvious promoting effect on the development of adventitious roots in mulberry cuttings, but its molecular mechanism has not yet been studied. In this research, transcriptome sequencing (RNA-seq) technology was employed to sequence the ‘Yueshenda 10’ mulberry during four distinct cutting stages. Through Kyoto Encyclopedia of Genes and Genomes (KEGG) and Gene Ontology (GO) enrichment analysis, shifts in gene expression and metabolic pathways were scrutinized, pinpointing the pivotal role of plant hormones in this context. Furthermore, using Weighted Gene Co-Expression Network Analysis (WGCNA), the study analyzed gene expression across all samples, identifying two modules, “black” and “blue”. These modules were predominantly expressed in the treatment group during the rooting phase and minimally expressed in the control group. Critical genes such as gene21267 and gene16291 from the black module, alongside gene18291 and gene20028 from the blue module, were identified as key to the rooting success of the ‘Yueshenda 10’ cuttings. This investigation not only supports the nutrient propagation and effective use of mulberry trees but also clarifies the molecular basis of adventitious root formation in these plants, extending the research to other related species. This work fosters the diversification and enhancement of the mulberry industry chain.