Cold stress severely limits legume productivity, threatening global food security, particularly in climate-vulnerable regions. This review synthesizes advances in understanding and enhancing cold tolerance in key legumes (chickpea, soybean, lentil, and cowpea), addressing three core questions: (1) molecular/physiological foundations of cold tolerance; (2) how emerging technologies accelerate stress dissection and breeding; and (3) integration strategies and deployment challenges. Legume cold tolerance involves conserved pathways (e.g., ICE-CBF-COR, Inducer of CBF Expression, C-repeat Binding Factor, Cold-Responsive genes) and species-specific mechanisms like soybean’s GmTCF1a-mediated pathway. Multi-omics have identified critical genes (e.g., CaDREB1E in chickpea, NFR5 in pea) underlying adaptive traits (membrane stabilization, osmolyte accumulation) that reduce yield losses by 30–50% in tolerant genotypes. Technologically, AI and high-throughput phenotyping achieve >95% accuracy in early cold detection (3–7 days pre-symptoms) via hyperspectral/thermal imaging; deep learning (e.g., CNN-LSTM hybrids) improves trait prediction by 23% over linear models. Genomic selection cuts breeding cycles by 30–50% (to 3–5 years) using GEBVs (Genomic estimated breeding values) from hundreds of thousands of SNPs (Single-nucleotide polymorphisms). Advanced sensors (LIG-based, LoRaWAN) enable real-time monitoring (±0.1 °C precision, <30 s response), supporting precision irrigation that saves 15–40% water while maintaining yields. Key barriers include multi-omics data standardization and cost constraints in resource-limited regions. Integrating molecular insights with AI-driven phenomics and multi-omics is revolutionizing cold-tolerance breeding, accelerating climate-resilient variety development, and offering a blueprint for sustainable agricultural adaptation.

Low-temperature stress severely restricts the growth, development, and yield of bitter gourd (Momordica charantia L.), a warm-loving crop with inherent low cold tolerance. NAC transcription factors (TFs) serve as crucial regulators in plant responses to abiotic stresses like cold, while their roles in coping with cold stress in bitter gourd remain unclear. This study identified cold-responsive genes in bitter gourd and characterized the candidate NAC TF McNAC087 through transcriptome analysis. Transcriptome sequencing of cold-tolerant (R) and cold-sensitive (S) bitter gourd inbred lines under 5 °C stress (0 h, 6 h, 12 h, 24 h) revealed 1157 co-expressed differentially expressed genes (DEGs), enriched via Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis in cold tolerance-related pathways (signal transduction, carbohydrate/amino acid metabolism). RT-qPCR showed higher McNAC087 expression in R than S under cold stress, and subcellular localization confirmed it as a nucleus-localized protein. McNAC087 overexpression in Arabidopsis enhanced cold tolerance after sequential stress (−14 °C for 1.5 h, 4 °C for 16 h, and 22 °C recovery for 2 days), with less damage compared to wildtype (WT). Physiologically, overexpressing lines had higher proline, elevated superoxide dismutase/peroxidase/catalase (SOD/POD/CAT) activities, lower malondialdehyde/hydrogen peroxide/superoxide anion (MDA/H₂O₂/O₂⁻) accumulation under cold stress, and upregulated ICE-CBF-COR pathway marker genes (CBF1, DREB2A, RD29A, COR47). In conclusion, McNAC087 enhances Arabidopsis cold tolerance by regulating physiology and activating cold-responsive genes, providing insights for bitter gourd cold tolerance mechanisms and crop breeding.