Compositae-ParaLoss-1272: A complementary sunflower-specific probe set reduces paralogs in phylogenomic analyses of complex systems.

Premise: A family-specific probe set for sunflowers, Compositae-1061, enables family-wide phylogenomic studies and investigations at lower taxonomic levels, but may lack resolution at genus to species levels, especially in groups complicated by polyploidy and hybridization. Methods: We developed a Hyb-Seq probe set, Compositae-ParaLoss-1272, that targets orthologous loci in Asteraceae. We tested its efficiency across the family by simulating target enrichment sequencing in silico. Additionally, we tested its effectiveness at lower taxonomic levels in the historically complex genus Results: We report that Compositae-ParaLoss-1272 captured loci across all tested Asteraceae members, had less gene tree discordance, and retained longer loci than Compositae-1061. Most notably, Compositae-ParaLoss-1272 recovered substantially fewer paralogous sequences than Compositae-1061, with only ~5% of the recovered loci reporting as paralogous, compared to ~59% with Compositae-1061. Discussion: Given the complexity of plant evolutionary histories, assigning orthology for phylogenomic analyses will continue to be challenging. However, we anticipate Compositae-ParaLoss-1272 will provide improved resolution and utility for studies of complex groups and lower taxonomic levels in the sunflower family.