Format: ORAL

Tina Kiedaisch1, Diego Morales-Briones1, Gudrun Kadereit1 and Anže Žerdoner Calasan1

1 Ludwig Maximilian University of Munich, Munich, Germany

Amaranthaceae sensu stricto form a monophyletic group within the Amaranthaceae (including Chenopodiaceae) comprising 80 genera and 900 species. Amaranthaceae s.s. are found predominantly in tropical and subtropical regions worldwide. In Australia 10 genera with together c. 190 species occur, spread across the entire continent including also arid biomes. Current phylogenies are insufficient to understand the complex evolutionary history of the lineage which is challenging due to three whole genome duplication events, rapidly diversified sublineages and an unusual high number of widespread, often introduced weedy species. This rules out a genome skimming approach and suggests target capture methods as the more appropriate approach. We identified a new genetic marker set universally applicable across the entire Amaranthaceae s.s. lineage. The baits are based on 28 transcriptomes and a reference genome of Amaranthus hypochondriacus. A total of 10,612 orthologous and low-copy genes were identified in a previous comprehensive transcriptomic study and compared with the output of MarkerMiner. Following the genome reference, 73,262 exons were split and filtered based on criteria including a minimum length of 800bp, less than 50% missingness per sequence, more than 2% informativeness, a minimum of 75% pairwise identity, and a requirement of at least 15 sequences per alignment. The remaining 2,561 exons were manually checked to ensure the quality of the loci. The final probes target a total of 884 nuclear loci and 1.7 Mbp. Based on this set of carefully selected loci, we reconstruct the evolutionary history of the entire Amaranthaceae s.s. lineage with the first aim to investigate the origin, age and spread of Australian lineages of Amaranthaceae s.s.