LsCLE12 peptide delays senescence in lettuce and prolongs postharvest life of roses

The widespread use of chemical inputs in agriculture has raised concern over their long-term environmental and health impacts, driving demand for sustainable, natural product-based alternatives. Peptide-hormone signaling interactions, particularly those regulating senescence, are promising targets for developing such alternatives to advance postharvest technologies. However, most current insights stem from model species, limiting their translation to crops and ornamental plants. This study identifies the CLAVATA3/EMBRYO-SURROUNDING REGION-related (CLE) family CLE12 peptide (CLE12p) in Lactuca sativa as a peptide that shows potential for postharvest management of crops and ornamental flowers. CLE12p interacts with salt (NaCl), abscisic acid (ABA) and ethylene pathways, influencing lettuce development and morphology. Notably, CLE12p induced stomatal closure in a similar manner to that of ABA, suggesting overlapping signalling pathways. Transcriptomic analyses revealed how CLE12p modulates immune and defence responses, fluid transport, and leaf senescence, indicating a broader role in leaf senescence regulation similar to that of ethylene. Functionally, CLE12p delayed senescence in lettuce by preserving leaf greenness and water content following dark treatment and harvest. Additionally, CLE12p extended the longevity of cut roses by maintaining fresh weight and water content. These findings demonstrate the practical potential of CLE peptides in non-model species and support their application as natural tools for extending postharvest shelf life in crops and ornamental plants, paving the way for further exploration of their role in agricultural biotechnology. Overall design: L. sativa var. Little Gem were grown on MS basal medium under 24 h continuous light at 22°C. Four-day-old seedlings were transferred to the following treatment for 2 h incubation: control (H2O), ethanol control (0.02% ethanol), 10 µM ABA, 10 µM ACC, 10 µM CLE12p, 10 µM ABA + CLE12p and 10 µM ABA + ACC.