Post-Translational Regulation of Stress Resilience and Ornamental Quality: Mechanisms, Evidence, and Research Priorities

Ornamental plants can survive stress while losing the traits that determine their commercial value. Post-translational modifications (PTMs) connect environmental and developmental signals to protein activity, localisation, and lifetime, offering a regulatory link between stress perception and horticultural performance. This review examines phosphorylation, ubiquitination, and lysine acylation across four areas of ornamental research: membrane regulation in rose immunity, cold-responsive crotonylation and enzyme function in chrysanthemum, senescence and acyl metabolism in petunia, and photosynthetic responses in Rhododendron. A non-exhaustive structured audit of ten selected profiling records describes analytical confidence and functional scope separately, identifying opportunities to integrate proteome measurements, refine site assignments, and connect discovery datasets to native-species experiments. Targeted chrysanthemum studies illustrate the complementary contributions of biochemical residue assays and native genetic tests. Model-plant evidence for SUMOylation, cysteine-redox modifications, S-acylation, N- and O-glycosylation, protein methylation, and limited proteolysis extends the framework to additional regulatory layers. Direct causal links between specific covalent modifications and ornamental quality remain limited. We propose a research agenda combining matched analytical streams, time-resolved measurements, and controlled native perturbations, with flower opening, petal integrity, colour, scent, and vase life as explicit outcomes. Connecting PTM dynamics to protein function, recovery, and quality trade-offs can strengthen the mechanistic basis for improving stress resilience in ornamental plants.