Insights into the molecular mechanisms underlying responses of apple trees to abiotic stresses

Abstract

Apple (Malus × domestica) is a popular temperate fruit crop worldwide. However, its growth, productivity, and quality are often adversely affected by abiotic stresses such as drought, extreme temperature, and high salinity. Due to the long juvenile phase and highly heterozygous genome, the conventional breeding approaches for stress-tolerant cultivars are time-consuming and resource-intensive. These issues may be resolved by feasible molecular breeding techniques for apples, such as gene editing and marker-assisted selection. Therefore, it is necessary to acquire a more comprehensive comprehension of the molecular mechanisms underpinning apples’ response to abiotic stress. In this review, we summarize the latest research progress in the molecular response of apples to abiotic stressors, including the gene expression regulation, protein modifications, and epigenetic modifications. We also provide updates on new approaches for improving apple abiotic stress tolerance, while discussing current challenges and future perspectives for apple molecular breeding.

Acknowledgements

This project was supported by grants from the National Key Research and Development Project (2022YFD1602107), the National Natural Science Foundation of China (32172530), the Key S&T Special Projects of Shaanxi Province, China (2020zdzx03-01-02), and the Key S&T Special Projects of Shanxi Province, China (202201140601027-6).

Conflict of interest statement

The authors declare that they have no conflict of interest.

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