Species tree estimation of diploid Helianthus (Asteraceae) using target enrichment

Premise of the study: The sunflower genus Helianthus has long been recognized as economically significant, containing species of agricultural and horticultural importance. Additionally, this genus displays a large range of phenotypic and genetic variation, making Helianthus a useful system for studying evolutionary and ecological processes. Here we present the most robust Helianthus phylogeny to date, laying the foundation for future studies of this genus. Methods: We used a target enrichment approach across 37 diploid Helianthus species/subspecies with a total of 103 accessions. This technique garnered 170 genes used for both coalescent and concatenation analyses. The resulting phylogeny was additionally used to examine the evolution of life history and growth form across the genus. Key results: Coalescent and concatenation approaches were largely congruent, resolving a large annual clade and two large perennial clades. However, several relationships deeper within the phylogeny were mo...