Population Genomics analysis of Associated with in China Reveals That Geographical Distribution Influences Its Genetic Polymorphism.

Blackleg disease, a major threat to crops worldwide, is primarily caused by the pathogen . Investigating the genetic variation of is crucial for managing and preventing the disease in . To date, there is scarce genomic variation information available for populations of in China. In this study, 73 strains of canola stalks were collected from 12 provinces in China and subjected to re-sequencing. The 73 assemblies averaged 1340 contigs, 72,123 bp N50, and 30.17 Mb in size. In total, 9409 core orthogroups and 867 accessory orthogroups were identified. A total of 727,724 mutation loci were identified, including 695,230 SNPs and 32,494 indels. Principal component analysis (PCA) and population structure analysis showed that these strains could be divided into seven subgroups. The strains in most provinces were clustered into a single subgroup, suggesting a strong influence of the geographic environment on strain variation. The average nucleotide diversity (θπ) of all strains was 1.03 × 10, indicating important genetic diversity among strains from different regions of China. This study provides valuable resources for future comparative genomics, gives new insights into the population evolution of , and supports the development of strategies for managing blackleg disease in canola.