Assembly of sorghum TX2783 and TX436 genome

Sorghum bicolor, one of the most important grass crops worldwide, has been known to harbor high genetic diversity. With the available PacBio long-read sequencing and BioNano, we constructed chromosome-level genome assembly for two important sorghum inbred lines: TX2783 and TX436 to discover the large structural variations in sorghum. The final assembly of TX2783 consists of 19 scaffolds with a contig N50 25.6Mb, and the final assembly of TX436 consists of 18 scaffolds with a contig N50 20.3Mb. Together with other public sorghum genomes BTX623, TX430 and Rio, we identified extensive large structural variations among these sorghum genomes using TX2783 as a reference. Genome-wide scan of the disease resistance genes (R gene) showed high-level diversity in these five available sorghum genomes. To characterize the genes related to the high-level sugarcane aphid resistance in TXx2783, we mapped the resistance region locus to a NSB-LRR gene cluster on chromosome 6 using a RIL population. We also identified causal SVs which could contribute to sugarcane aphid resistance using Nanopore sequencing. In summary, this study provided the first overview of the extent of genomic structural variations, and R genes , in sorghum population, and potential targets for disease resistance breeding.