The revelation of genomic breed composition using target capture sequencing: a case of .

plants have good flood tolerance and thus were introduced into China from North America in the early 1900s. The subsequent decades of cross-breeding experiments within have produced many new hybrid cultivars in China while also creating confusion in the genetic background of plants. In the present study, target capture sequencing-derived SNP markers were used to reveal the genomic composition of different species and cultivars of . The results unraveled the phylogenetic relationship within and suggested the possibility of recent interspecific natural hybridization events. The introduced (Chinese) population is genetically similar to the native (North American) population, thus providing genetic evidence for historical introductions of . Hybrid categories of different cultivars of hybrid 'Zhongshanshan' were further identified, and their differences in parentage were revealed. Collectively, the findings provide evidence for understanding the genetics and hybridization of and shed light on the future breeding and cultivation of cultivars with great ecological and economic potential.