Abstract Detail

Systematics

Cavaliere, Dario Julian [1], Little, Damon [1].

Phylogenetic placement of Martyniaceae: it’s not the trichomes.

The relationships and circumscription of Martyniaceae have historically been unclear. Martyniaceae was originally classified in an informal group with genera of Pedaliaceae, which together were included in Bignoniaceae. The objective of this study was to elucidate the placement of the Martyniaceae within Lamiales using nuclear, plastid, and mitochondrial sequence data (atpB, matK, rps3, and D2-D3 expansion segment of 26S rDNA), along with morphological data. A detailed structural and histochemical report of trichomes is presented here as a step toward understanding variation between Martyniaceae and Pedaliaceae trichomes. The trichomes of Martyniaceae and Pedaliaceae differ both morphologically and chemically, but there is some conflict in the literature over the precise nature of the differences. The exudate of Pedaliaceae trichomes has been described as mucilaginous, and that of Martyniaceae as a sticky secretion containing sugars with an aldehyde functional group. The results indicate that the trichome exudate of both families are chemically similar as they are both at least partially composed of proteins and reductive sugars. The glandular trichomes of these families may have evolved chemically similar compositions, possibly in response to similar environmental conditions. Poorly–supported and conflicting results from maximum likelihood and parsimony analyses, with and without the inclusion of morphological data, indicate that the relationships between Martyniaceae and other families in Lamiales cannot confidently be reconstructed with the data gathered for this study, despite this we can infer that Martyniaceae and Pedaliaceae have similar exudate compositions.

1 - The New York Botanical Garden, Science, 2900 Southern Blvd, Bronx, NY, 10458, USA

Keywords:
Martyniaceae
phylogenetics
Trichomes.

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: PSY046
Abstract ID:630
Candidate for Awards:None