Leaf senescence is a critical physiological process during the growth and development of Moso bamboo ( Phyllostachys edulis ), yet the underlying molecular regulatory network remains unclear. In this study, we found that PheNAC6 expression was gradually and continuously upregulated during leaf development in Moso bamboo seedlings, with peak expression at the senescence stage. Heterologous expression of PheNAC6 in Arabidopsis thaliana and Oryza sativa demonstrated that PheNAC6 positively regulates leaf senescence. Further analyses revealed that PheNAC6 is involved in the abscisic acid (ABA)-mediated leaf senescence pathway: exogenous ABA treatment induced more pronounced senescence in PheNAC6 -overexpressing (OE) lines than in wild-type (WT) plants, and exogenous ABA also upregulated the transcription of PheNAC6 . Additionally, PheNAC6 directly activated the expression of PheABCG40–1 (encoding an ABA transporter) and the senescence-associated gene (SAG) PheSAG12 , indicating that PheNAC6 participates in ABA-mediated leaf senescence through the PheNAC6- PheABCG40–1 regulatory module. Thus, we propose a pivotal regulatory module whereby PheNAC6 promotes ABA-related leaf senescence by activating PheABCG40–1 . Our findings uncover a key molecular mechanism governing Moso bamboo leaf senescence and provide a theoretical foundation for modulating vegetative growth and breeding senescence-resistant varieties through ABA signaling. • PheNAC6 promotes leaf senescence in Moso bamboo as a positive regulator. • The PheNAC6- PheABCG40–1 module mediates ABA transport-linked leaf senescence in Moso bamboo. • Identification of the ABA- PheNAC6 positive feedback loop and PheNAC6 as a target for senescence-resistant crop breeding.
Cheng et al. (2026) studied this question.