Abstract Detail


Sanbonmatsu , Katie K [1], Mukai, Maya [2], Spalink, Daniel [2], BOHS , LYNN ALLISON [3].

Capsi-conundrum: Resolving Relationships within Capsiceae (Solanaceae).

The nightshade family Solanaceae is one of the world’s most economically important plant families, and contains potatoes, tomatoes, peppers, tobacco, and petunia. Within this family, the genus Capsicum (~40 species) includes the chili and bell peppers. Some Capsicum species are well known for their pungent fruits, a trait imparted by unique capsaicinoids. The five cultivated species of Capsicum constitute a multi-billion-dollar industry, but the remaining species are under-studied. The sister genus to Capsicum, Lycianthes, is much larger (~200 species) and has a broader distribution. Evolutionary relationships among the species of the two genera have not been well-investigated and the relationship between Capsicum and Lycianthes is still unclear. The apparently rapid diversification of this group has made phylogenetic analysis difficult. Previous studies reveal a paraphyletic Lycianthes with a nested Capsicum, but this relationship is weakly supported. To obtain better phylogenetic resolution, we utilized Illumina sequencing to target ~2000 loci and compared these results to those obtained using a Sanger sequencing dataset. Here, we present three phylogenies for comparison. The Sanger tree was constructed using data from nuclear (ITS, waxy) and chloroplast (ndhF and trnT-F) genes for 62 species. The other two trees are based on Illumina data. The “concatenated tree” is a maximum likelihood tree built from a concatenated alignment of 1467 genes for 42 taxa. The species tree was developed from 131 genes using Bayesian concordance analysis, which can account for discordance between gene trees. All three trees have nearly identical topologies, and all recover Capsicum as a clade nested within a paraphyletic Lycianthes. Overall low concordance factors point to incomplete lineage sorting as the primary cause of discordance among gene trees.

1 - University of Utah, Department of Biology, 257 South 1400 East, Salt Lake City, UT, 84112, USA
2 - University Of Utah, Department Of Biology, 257 South 1400 East, Salt Lake City, UT, 84112, United States
3 - University Of Utah, Department Of Biology, 257 South 1400 East, 201 South Biology, Salt Lake City, UT, 84112, United States

genealogical discordance
Incomplete Lineage Sorting

Presentation Type: Poster
Number: PPH007
Abstract ID:626
Candidate for Awards:None

Copyright © 2000-2018, Botanical Society of America. All rights reserved