Abstract Detail

Anatomy and Morphology

Hutcheson, Holly [1], Cohen, Jim [2].

Comparative floral development of Oreocarya crassipes (Boraginaceae), a heterostylous species.

Botanists have been interested in heterostylous flowers for over 150 years, with much of the early details described by Darwin in his book Different Forms of Flowers. Much research has focused on the ecological and genetic differences between the two morphs. In the present study, floral developmental patterns of two morphs of Oreocarya crassipes (Boraginaceae), an endangered species endemic to West Texas, were examined at macroscopic and microscopic levels. At the macroscopic level, it is hypothesized that the differences in anther and stigma heights are due to the growth rate of the shorter organ slowing down, and at the microscopic level, it is hypothesized that the cause of the differences between the anther and stigma heights of the two morphs is due to a combination of different cell lengths and cell numbers in the organs. For macroscopic patterns, flowers at various stages of development were dissected, and the corolla length and the heights of the anthers and stigmas were measured. For microscopic patterns, inflorescences and individual flowers were prepared for histological examinations, and this was followed by measurements of cell lengths of the corolla and style in flowers at various stages of development. For anther height development, the short-style (SS) morph has a faster rate of development than the long-style (LS) morph. For style length, the styles of the LS and SS morphs develop at approximately the same initial rate of growth, but the style of the LS morph continues to elongate for a longer period of time compared to that of the SS morph, in which growth slows when the floral bud is approximately 25% of its mature length. At the microscopic level, the LS flowers had a larger range of cell sizes compared to the flowers of the SS morph. Standard least squares models, implemented in JMP, provide evidence that the development of the corolla cells, between morphs, is statistically significantly different, but this is not the case for the development of the stylar cells. At anthesis, the corolla and stylar cells of the LS morph are longer than those of the SS morph.

1 - Kettering University, 1700 University Avel., Flint, MI, 48504, USA
2 - Kettering University, Applied Biology, 1700 University Ave., Flint, MI, 48504, USA

Keywords:
Boraginaceae
Heterostyly
Floral development
Oreocarya
breeding system.

Presentation Type: Poster
Session: P, Anatomy and Morphology
Location: Exhibit Hall/Omni Hotel
Date: Monday, June 26th, 2017
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: PAM002
Abstract ID:268
Candidate for Awards:None