Abstract Detail

Systematics Section/ASPT

Dixon, Jennifer [1], Clark, Lynn G. [2], HORNER , HARRY T [3].

Preliminary Analysis of Pollen Ultrastructure in Poaceae.

The presence of intraexinous channels in the pollen wall was proposed as a synapomorphy for the Poaceae in 1985. At that time, however, only three species of the Poaceae had been sampled with TEM methods and since then, little work has been done to determine if this character is found throughout the Poaceae. Investigation using existing literature reveals evidence of intraexinous channels in nine species representing two (Pooideae, Panicoideae) of the twelve subfamilies of Poaceae, a remarkably small sample size as the basis for classifying a character as a synapomorphy. The existence of these channels within the exine of the pollen is observable only using advanced techniques such as transmission or scanning electron microscopy but the preparation techniques can vary. Most TEM preparation methods for pollen analysis utilize anacetolysis process which destroys the cellulosic components of the pollen but retains the sporopollenin exine; the specific protocols used have a direct impact on the appearance of pollen ultrastructure which makes using previous literature, each employing different techniques,essentially uninformative. In this talk we will outline our research goals for analyzing intraexinous channels in each sub-family of Poaceae to develop a phylogenic map of the character within the family. We will discuss the importance of developing a singular protocol as well as the far-reaching importance of understanding this key character.

1 - Iowa State University, Department of Ecology, Evolution, and Organismal Biology, Bessey Hall, Ames, Iowa, 50011, USA
2 - Iowa State University, Department Of Ecology, Evolution, And Organismal Biology, 251 Bessey Hall, Ames, IA, 50011-1020, USA
3 - Iowa State University, Genetics, Development And Cell Biology Dept, 3A Bessey Hall, AMES, IA, 50011-1020, USA

Keywords:
Poaceae
pollen
TEM.

Presentation Type: Oral Paper:Papers for Sections
Session: 13
Location: Pines South/Boise Centre
Date: Monday, July 28th, 2014
Time: 5:15 PM
Number: 13015
Abstract ID:785
Candidate for Awards:George R. Cooley Award