Progress of collection, conservation and innovative utilization of strawberry germplasm resources in the National Peach and Strawberry Germplasm Resources Repository (Beijing)

Cultivated strawberry (Fragaria × ananassa, 2n=2x=56), an octoploid perennial herbaceous plant, is one of the most important commercial crops and is widely cultivated in the world. According to statistics from the Food and Agriculture Organization of the United Nations (FAO) in 2022, China leads the global strawberry industry, with a cultivation area of 148 000 hectares and an annual production of 3 988 000 tons. The strawberry industry, characterized by its short growth cycle and high economic returns, plays a pivotal role in promoting modern agricultural development and rural revitalization in China. Moreover, China is also one of the primary distribution regions for Fragaria species. With 13 out of the 25 known species naturally distributed across the country, China has a rich diversity of wild strawberry germplasm. These resources serve as a valuable genetic reservoir, providing critical support for strawberry breeding programs and the sustainable development of the strawberry industry. The National Peach and Strawberry Germplasm Resources Repository (Beijing) established in 1981 is one of the na-tional strawberry germplasm resources conservation units, and mainly undertakes the tasks of strawberry germplasm resources collection, preservation and evaluation as well as resource sharing and utilization. By the end of December 2024, totally 418 accessions of strawberry germplasm have been collected, preserved, and cataloged in the repository, including wild species, local varieties and bred varieties. Relying on the those resources, systematic identification and evaluation of agronomic traits have been carried out every year. Fourteen germplasms have been screened out with excellent and specific traits, such as good quality, high resistance, day-neutral and high yielding, etc. These germplasms can be used in production utilization and cultivar selection and breeding, thus promoting the upgrading of strawberry varieties in China. A total of 1655 accessions have been offered and utilized for 125 organizations involving universities, colleges, research institutes and production and processing companies. Using the superior germplasms as backbone parents, 25 new strawberry cultivars have been bred and released with high fruit quality and different maturity periods. A high-resolution genome of Fragaria pentaphylla was assembled for genome sequencing, providing a good reference for understanding the genetics of the endemic Fragaria species in China. The phylogenetic analysis based on chloroplast genomes revealed that the drastic global temperature change and uplifting of the Qinghai-Tibet plateau might have driven the formation of taxa and polyploidization in the genus Fragaria. Meanwhile, studies focusing on the mechanisms underlying strawberry quality and resistance traits have been conducted. By integrating phenotyping and genotyping data, including metabolomic, transcriptomic, and gene expression analyses, candidate genes have been identified, laying the foundation for the genetic regulation of these traits. Fruit aroma has been a major focus of our research utilizing germplasm resources. We established the gas chromatography-mass spectrometry (GC-MS) method for volatile substances detection of strawberry fruits. Then the genetic analysis was performed on nerolidol, one of the key components, based on F1 population derived from specific cultivars screened by evaluation. Key genes like nerolidol synthase gene FaNES1 and alcohol acyltransferase gene FvAATW2 were identified to aid in fruit aroma regulation. For the other fruit quality traits, we found that the aldo-keto reductases gene AKR23 could regulate both ascorbic acid and anthocyanin content in strawberry fruits. And the accumulation of soluble sugars and vitamin C was highly likely to be synchronously regulated by MYB, bHLH, NAC, AP2 and bZIP family members during fruit ripening. We revealed that the response mechanisms of strawberry to salt stress was different in selected germplasm. The genome-wide analysis of tubby-like protein gene family (TLP) showed that the gene members were widely involved in strawberry abiotic stress response such as salinity, drought, high and low temperatures, as well as in the regulation of strawberry growth and development. In addition, it was found that heterologous expression of the Arabidopsis thaliana ROOTY (RTY) gene in strawberry could improve the drought resistance. Simultaneously, the practical application of the strawberry germplasm resources in the industry has been significantly strengthened. Farmers adopted the elite germplasm resources screened or the new cultivars bred by us have realized substantial economic gains. Furthermore, a series of national and international exhibitions and conferences centered on the strawberry industrial chain were successfully held in the repository, facilitating the widespread adoption of new cultivars and cutting-edge technologies. These efforts have collectively contributed to the sustainable growth and global competitiveness of China’s strawberry industry. In summary, this paper comprehensively reviews the progress achieved by the National Peach and Strawberry Germplasm Resources Repository (Beijing) in the collection, preservation, innovation, sharing, and utilization of strawberry germplasm resources. Furthermore, it outlines future research directions, aiming to provide valuable insights and references for the effective exploitation of strawberry germplasm resourc-es and the sustainable development of China’s strawberry industry.