Kiwifruit genomics and applications: Recent advances, current challenges and future prospects

Kiwifruit (Actinidia spp.) is an economically important horticultural fruit crop native to China, valued globally for its superior flavor, rich nutrients, and extremely high vitamin C content. The genus Actinidia exhibits extraordinary genetic diversity characterized by wide ploidy variations ranging from diploid to decaploid and an obligate dioecious reproductive system. These unique biological features promote frequent natural hybridization and introgression, generating abundant genomic and phenotypic variations and forming a rich germplasm resource pool for genetic research and breeding applications. Despite the existence of more than 50 documented kiwifruit species, only a few have been widely domesticated and commercially cultivated due to a relatively short domestication and industrialization history. Since its introduction to New Zealand in 1904, kiwifruit has rapidly developed into an internationally popular fruit commodity, with continuous market expansion driven by the constant improvement of new elite cultivars. In recent decades, advances in high throughput sequencing and multi omics technologies have greatly accelerated kiwifruit biological research, covering plant development, fruit quality formation, stress adaptation, and disease resistance. The release of the first kiwifruit reference genome in 2013 marked a revolutionary turning point, providing fundamental genomic resources for systematic exploration of gene function, evolutionary mechanisms, and trait regulatory networks. Accumulating genomic, transcriptomic, metabolomic, and epigenomic data have enabled precise gene mining, fine trait mapping, and in-depth analysis of key metabolic pathways underlying important agronomic characteristics. This review systematically summarizes the major progress in kiwifruit multi omics research over recent years, focusing on genome assembly, germplasm genetic diversity, molecular basis of core agronomic traits, and regulatory mechanisms of key biological processes. It further elaborates the application potential of genomic selection and gene editing technologies in modern kiwifruit molecular breeding. Additionally, the current technical bottlenecks and research challenges in kiwifruit genomic studies are discussed, and future research directions and innovative breeding strategies are prospected. This review aims to provide comprehensive theoretical references and new insights for the further excavation of excellent gene resources and the cultivation of high quality, high yield, and stress resistant kiwifruit varieties.