Biotechnological Advances and Multi‐Omics Insights for Fruit Quality, Postharvest Biology, and Genetic Improvement in Litchi ( Litchi chinensis Sonn.)

Litchi ( Litchi chinensis Sonn.) is a high‐value subtropical fruit crop widely appreciated for its unique flavor, nutritional richness, and commercial importance in Asia and other tropical and subtropical regions. However, genetic improvement and large‐scale cultivar development in litchi have progressed slowly because of its prolonged juvenile phase, high heterozygosity, self‐incompatibility, and limited regeneration capacity. Nevertheless, recent advances in molecular biology, genomics, and biotechnology have substantially improved understanding of litchi fruit development, quality formation, stress responses, and postharvest physiology. This review critically synthesizes current progress in litchi biotechnology, encompassing chromosome‐scale genome assembly, molecular marker systems, SNP resources, and functional genomics studies that have identified major regulatory genes and transcriptional networks associated with flowering, pigmentation, senescence, stress adaptation, and fruit quality traits. We further highlight how transcriptomic, metabolomic, and multi‐omics analyses have revealed coordinated regulatory networks involving hormone signaling, redox homeostasis, energy metabolism, flavonoid biosynthesis, and postharvest deterioration during fruit development and storage. Recent developments in tissue culture, somatic embryogenesis, Agrobacterium ‐mediated transformation, and CRISPR/Cas‐based genome editing are also evaluated as enabling platforms for functional validation and precision improvement of commercially important traits, including shelf life and fruit quality. Collectively, these advances demonstrate a transition from descriptive molecular studies toward integrated multi‐omics and translational biotechnological strategies for sustainable litchi improvement. Future progress will depend on the integration of high‐resolution genomic resources, efficient regeneration systems, and predictive breeding approaches to develop climate‐resilient, high‐quality cultivars with improved postharvest performance.