Abstract Detail

Angiosperms353: A new essential tool for plant systematics

McDonnell, Angela [1], Martine, Christopher [2].

Phylogenomics and Breeding System Evolution of Australian Solanum (“S. dioicum group”, Solanaceae).

Just 1% of species in Solanaceae exhibit a dioecious breeding system, with nearly all occurrences happening within the “spiny solanums” of the Australian Monsoon Tropics. In these species, morphologically hermaphrodite individuals produce inaperturate pollen that renders them functionally female. The “S. dioicum group”, consisting of functionally dioecious taxa and a set of andromonoecious relatives has been a subject of systematic study for decades, yet the relationships among groups of species and, thus, the patterns in breeding system evolution are still unknown. We aim to illuminate the evolutionary history of the lineage using targeted enrichment data, evaluate areas and potential sources of phylogenetic conflict, reconstruct the evolution of diverse breeding systems, and revisit previous hypotheses regarding reproductive characters. We include 172 individuals representing 102 taxa and report on data obtained via the Angiosperms 353 probe set. HybPiper recovered 340 loci that reveal substantial conflict in data among clades. Generally, our results support some previously reported species-level relationships and highlight where processes of incomplete lineage sorting and hybridization have occurred. Against a background of hermaphroditism, we detect one origin of andromonoecy, one or two origins of dioecy, and one reversal to the hermaphroditic state within the “S. dioicum group”. Our study provides a framework of evolutionary relationships in Australian spiny Solanum; most inferred species relationships are well supported across multiple analyses while the detected discordance among gene trees highlights a complex history that includes rapid speciation, incomplete sorting of ancestral variation, and hybridization. We highlight the evolution of diverse reproductive traits and suggest that breeding system transitions in this group are not only more common than previously thought, but also underlie an ongoing radiation requiring further taxonomic effort.

1 - Chicago Botanic Garden, Science Dept., 1000 Lake Cook Road, Glencoe, IL, 60022, United States
2 - Bucknell University, Biology, 1 Dent Drive, Lewisburg, Pennsylvania, 17837, United States

Keywords:
Solanum
phylogenomics
Breeding System
Australia
Angiosperms353
Target Enrichment.

Presentation Type: Symposium Presentation
Session: SY4, Angiosperms353: A new essential tool for plant systematics
Location: Virtual/Virtual
Date: Thursday, July 30th, 2020
Time: 1:00 PM
Number: SY4007
Abstract ID:238
Candidate for Awards:None