Development of a Core Collection of Six-Rowed Hulless Barley from the Qinghai-Tibetan Plateau

A core collection reflects the diversity of the larger germplasm collection and makes the evaluation of genetic resources more effective. To improve barley germplasm management, we propose the construction of a core genetic collection derived from a set of 204 six-rowed hulless barley accessions (39 registered cultivars and 165 landraces) native to the Qinghai-Tibetan Plateau (QTP). A sampling percentage of 20% was predicted by the maximization strategy. Five different sampling strategies (Mstrat, Random, REMC, SBS, and SFS) were applied to establish 5 primary core collections from the original 204 accessions using 1750 single-nucleotide polymorphism (SNP) markers. After the evaluation and analysis of core collection representativeness, the Mstrat strategy was determined to be a valid method for developing a core collection. A total of 41 barley accessions were obtained, including 11 registered cultivars and 30 landraces. Genetic structure analysis of the 204 barley accessions showed that the core collection was evenly distributed throughout the initial collection, indicating that the core collection represented the larger germplasm well. A subset of 28 SNP markers were produced and used to distinguish all 204 barley accessions from each other. We believe the collection of 28 SNP markers will be incredibly helpful to barley breeders. Furthermore, the core collection ensures the long-term conservation of genetic resources and will support improvements to six-rowed hulless barley from the Qinghai-Tibetan Plateau.