Segmental allopolyploidy in action: Increasing diversity through polyploid hybridization and homoeologous recombination.

摘要: PREMISE OF THE STUDY The genetic bottleneck of polyploid formation can be mitigated by multiple origins, gene flow, and recombination among different lineages. In crop plants with limited efforts to increase diversity have limitations. Here we used lineage in peanut, an allotetraploid likely single origin, crossing a novel allopolyploid genotype selecting improved lines. METHODS Single backcross progeny from cultivated peanut × wild species-derived cross were studied over successive generations. Using assumptions that encompass segmental allotetraploidy, nucleotide polymorphisms whole-genome sequence data infer genome structures. KEY RESULTS Selected lines, despite high proportion alleles, are agronomically adapted, productive, disease resistances. Wild alleles mostly substituted homologous segments the genome. Regions dispersed characteristic conversion, also occurred. However, chromosome sometimes replaced peanut's homeologous subgenome; A. ipaensis B hypogaea A subgenome (~0.6%), duranensis (~2%). Furthermore, some regions historically lost "recovered" (effectively reversing "polyploid ratchet"). These processes resulted lines new structure variations. CONCLUSIONS Genetic was introduced allele introgression, introducing results highlight special possibilities allotetraploidy using mirroring what occurs natural allopolyploids origins.