Flavonoids as key players in cold tolerance: molecular insights and applications in horticultural crops

Abstract

Cold stress profoundly affects the growth, development, and productivity of horticultural crops. Among the diverse strategies plants employ to mitigate the adverse effects of cold stress, flavonoids have emerged as pivotal components in enhancing plant resilience. This review was written to systematically highlight the critical role of flavonoids in plant cold tolerance, aiming to address the increasing need for sustainable horticultural practices under climate stress. We provide a comprehensive overview of the role of flavonoids in the cold tolerance of horticultural crops, emphasizing their biosynthesis pathways, molecular mechanisms, and regulatory aspects under cold stress conditions. We discuss how flavonoids act as antioxidants, scavenging reactive oxygen species (ROS) generated during cold stress, and how they regulate gene expression by modulating stress-responsive genes and pathways. Additionally, we explore the application of flavonoids in enhancing cold tolerance through genetic engineering and breeding strategies, offering insights into practical interventions for improving crop resilience. Despite significant advances, a research gap remains in understanding the precise molecular mechanisms by which specific flavonoids confer cold resistance, especially across different crop species. By addressing current knowledge gaps, proposing future research directions and highlighting implications for sustainable horticulture, we aim to advance strategies to enhance cold tolerance in horticultural crops.

Acknowledgements

This work was supported by grants from Ningxia Hui Autonomous Region Key R&D Program (2023BCF01003), National Natural Science Foundation of China (32472711), and Agricultural Breeding Project of Ningxia Hui Autonomous Region (NXNYYZ202101).

Author contributions

W.R.X and J.X.L. designed this review. J.X.L., Q.H.Y., C.L., and N.B.Z. conducted the literature review and wrote the manuscript. W.R.X. carefully compiled and revised the paper. All authors approved the final submission.

Data availability

The authors confirm that all data in this study are available and can be found in this article.

Conflict of interest statement

The authors declare the absence of conflict of interest.

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