Abstract Detail

Reproductive Processes

Eberl, Emma [1], Friedman, Jannice [1].

Post-pollination processes in a dioecious wind-pollinated plant.

Wind-pollinated plants have small flowers with long, exerted stigmas that protrude into the airstream to maximize pollen capture under aerodynamic constraints. The long or feathery stigmas are typically receptive along their entire length. In some wind-pollinated species, stigmas continue elongating after initial anthesis, but it is unclear whether this depends on successful pollen capture and fertilization. Furthermore, the distance travelled by a pollen tube will depend on where along the stigma it lands, which has implications for pollen-tube competition and/or mate choice. While most wind pollinated flowers lack showy pigmentation, some species have red or purple pigmented flowers which may play a role in protecting stigmas and gametophytes during unfavorably low temperatures or high UV. In this project, we will investigate pollen tube and stylar interactions and their effects on post-pollination processes in Amaranthus tuberculatus, a dioecious wind-pollinated annual. In particular, we will use manipulative experiments in growth chambers and the field to test the role of stigma elongation for pollen capture; how the position of pollen along the stigma affects pollen tube growth; and the impact of stigma pigmentation on pollen germination and tube growth. We predict that (1) stigmas will continue elongating if they are not pollinated and longer stigmas will capture more pollen, (2) pollen tubes from pollen grains that land closer to the base of the style will outcompete more distant pollen tubes, which could undermine opportunities for sexual selection, and (3) stigma pigmentation will provide protection under high UV and aid pollen germination. This research represents novel approaches to understanding floral trait variation in wind-pollinated plants.

Related Links:
Flora of North America

1 - Queen's University, Biology, 99 University Avenue, Kingston, ON, K7L3N6, Canada

wind pollination
post-pollination processes
stigma length
stigma pigmentation
pollen tubes
pollen germination
sexual selection.

Presentation Type: Poster
Session: P, Reproductive Processes Posters
Location: Virtual/Virtual
Date: Thursday, July 30th, 2020
Time: 5:00 PM Time and date to be determined
Number: PRP001
Abstract ID:694
Candidate for Awards:None

Copyright © 2000-2020, Botanical Society of America. All rights reserved