A step forward toward improved cold tolerance in rice: integrating physiological insights with cutting-edge genomic approaches.

Abstract

Cold stress (CS) is a major abiotic factor that significantly affects rice growth, development, and productivity. To withstand CS, rice plants have evolved intricate mechanisms that enable them to detect external signals and respond to changing environmental conditions. Understanding the physiological and molecular mechanisms underlying cold tolerance (CT) is therefore crucial for developing rice cultivars that can thrive under cold conditions. To date, a limited number of genes/QTLs associated with CT, such as: Ctb1, COLD1, COLD6, qLTG3-1, SGD1, and CTB4a, have been cloned and well studied. These genes play essential roles in the plant's response to CS by regulating various stress-related pathways, including reactive oxygen species (ROS) scavenging, osmotic regulation, and signal transduction. The physical co-localization of OsSRFP1 (associated with CT at the seedling stage) and OsMTACP2 (associated with CT at the reproductive stage) on chromosome 3 (between 13.1-13.3 Mb) suggests the potential for simultaneous introgression of these traits into recipient cultivars using donor parents carrying the desirable alleles. Genomic selection, powered by high-throughput genotyping technologies, enhances the accuracy and efficiency of identifying cold-tolerant genotypes. Additionally, integrating multi-omics approaches with gene-editing technologies offers a comprehensive strategy to uncover the complex molecular networks and regulatory pathways involved in CT, thereby identifying potential targets for genetic improvement. Overall, this review emphasizes the potential of integrating molecular, physiological, and genomic tools to develop rice cultivars resilient to CS, thereby contributing to global food security in the context of climate change.