Tropical vulnerability and temperate resilience: molecular and physiological insights into cold stress adaptation in oil palm.

Cold stress is a major abiotic constraint limiting the growth and productivity of oil palm (Elaeis guineensis). Its high sensitivity to chilling causes physiological impairment, metabolic disruption, and reduced oil yield and quality. This review summarizes physiological, biochemical, and molecular mechanisms of cold stress responses in oil palm, with comparative insights from rapeseed and soybean. Key pathways, including Ca2+ signaling, MAPK cascades, and the ICE-CBF/DREB network, coordinate membrane lipid remodeling, osmotic adjustment, antioxidant defense, and hormonal regulation. Key genes (EgCBF, EgICE1, EgNCED, EgFAD2, EgSAD, EgP5CS) and transcription factors (EgWRKY, EgNAC, EgMYB) contribute to stress adaptation. However, these responses may be insufficient under prolonged or recurrent chilling, potentially disrupting lipid remodeling, water relations, and plant performance. Advances in GWAS, QTL mapping, multi-omics, genomic selection, and genome editing provide opportunities to improve cold resilience, particularly against episodic chilling events and abrupt temperature fluctuations that may become increasingly important under climate change.