The study reveals that the Arabidopsis SnRK2.4 and SnRK2.10 kinases, previously known for stress responses, are activated during normal developmental leaf senescence and act redundantly to promote this process. They stimulate ABA accumulation by up‑regulating NCED2 and modulate expression of ABA‑responsive and senescence genes, while also enhancing MAPKKK18 expression and activity, linking SnRK2 signaling to MAPK pathways.

The study generated a temporal physiological and metabolomic map of leaf senescence in diverse maize inbred lines differing in stay‑green phenotype, identifying 84 metabolites associated with senescence and distinct metabolic signatures between stay‑green and non‑stay‑green lines. Integration of metabolite data with genomic information uncovered 56 candidate genes, and reverse‑genetic validation in maize and Arabidopsis demonstrated conserved roles for phenylpropanoids such as naringenin chalcone and eriodictyol in regulating senescence.