Abstract Detail

Systematics

Sears, Nicole L [1], Tippery, Nicholas P [2].

Evidence for two allopolyploid speciation events during the diversification of Nymphoides (Menyanthaceae).

Polyploidization drives diversification in a wide variety of plant groups, however the multiple gene copies that result from polyploidization also present a challenge for phylogenetic reconstruction. In the aquatic plant genus Nymphoides (floating-heart), previous molecular phylogenetic analyses using nuclear (ITS) and plastid (matK/trnK) data produced incongruent trees. In order to resolve the incongruence, we obtained additional sequence data from two nuclear loci: phytoene desaturase (PDS) and transmembrane nine (TMN1), and one plastid locus: the trnT-trnF spacer. Polymorphic sequences for PDS and TMN1 in five species were subcloned to reveal two independent copies of each gene. Phylogenetic analyses that included subcloned sequences indicated that two clades likely descended from allopolyploid ancestors: one clade of neotropical species (N. fallax, N. grayana, N. humboldtiana) and another of North American species (N. aquatica, N. cordata). Together these represent all Nymphoides species that are native to the Americas, and their allopolyploid status is consistent with their tetraploid chromosome numbers. By including subcloned sequences in a comprehensive phylogenetic analysis of Nymphoides, we were able to resolve and explain some of the previous incongruence between nuclear and plastid data.

1 - University of Wisconsin - Whitewater, 800 W Main St, Whitewater, WI, 53190, USA
2 - University Of Wisconsin - Whitewater, Department Of Biological Sciences, 800 W Main St, 800 W Main St, Whitewater, WI, 53190, USA

Keywords:
aquatic plants
Asterales
hybridization
Menyanthaceae
Nymphoides
phylogenetics
polyploidy
Systematics.

Presentation Type: Poster
Session: P, Systematics Section/ASPT Posters
Location: Exhibit Hall/Savannah International Trade and Convention Center
Date: Monday, August 1st, 2016
Time: 5:30 PM This poster will be presented at 6:15 pm. The Poster Session runs from 5:30 pm to 7:00 pm. Posters with odd poster numbers are presented at 5:30 pm, and posters with even poster numbers are presented at 6:15 pm.
Number: PSY048
Abstract ID:244
Candidate for Awards:None