Abstract Detail

Horsetails Through Form, Space, and Time

Ambrose, Barbara [1], Vasco, Alejandra [2].

Equisetum morphology: An evo-devo perspective.

The morphology, evolution, and phylogenetic position of Equisetum have been highly debated. Recent molecular phylogenies place Equisetum as sister to all ferns, a position that is more in agreement with the morphological analyses that include fossils. Also contentious has been the morphology of the entire Equisetum shoot, which does not resemble any other extant fern and has been frequently considered closer to lycophytes than to ferns. We are using an evolutionary developmental approach to better understand the morphology of Equisetum. We performed phylogenetic analyses of candidate shoot, leaf, and sporangium developmental genes: Class I KNOX, NAM/CUC, KANADI and Class III HD-Zips (C3HDZ). We performed in situ hybridization in Equisetum diffusum and Equisetum hyemale to provide insights into Equisetum morphology. For example, we found that the expression pattern of EdC3HDZ2 in the leaf adaxial region is more similar to the fern leaf expression pattern as opposed to the lack of C3HDZ gene expression in lycophyte leaves. This indicates that Equisetum shares leaf developmental mechanisms with ferns and seed plants and not with lycophytes.

1 - The New York Botanical Garden, 2900 Southern Blvd., Bronx, NY, 10458, USA
2 - Instituto de Biologí­a, UNAM, Departamento de Botánica, Circuito Exterior s/n, Ciudad Universitaria, A.P. 70-367, Mexico D.F., 04510, Mexico

Keywords:
ferns
leaf development
megaphyll
microphyll.

Presentation Type: Symposium Presentation
Session: SY03, Horsetails through form, space and time
Location: Oglethrope Auditorium/Savannah International Trade and Convention Center
Date: Monday, August 1st, 2016
Time: 3:45 PM
Number: SY03007
Abstract ID:718
Candidate for Awards:None