Abstract Detail

Ecological Section

Price, Taina M. [1].

Latitudinal variation in seed germination requirements and phenological traits in Phemeranthus parviflorus (Nutt.) Kiger (Montiaceae).

Phemeranthus parviflorus (Nutt.) Kiger (Montiaceae) is a widespread succulent perennial, occurring in dry, open rocky and sandy habitats from northern Mexico to the Dakotas. The plants usually die back to the ground each winter and regenerate in the spring from resting buds on a usually underground caudex. The flowering period extends throughout the summer, with more or less continuous production of flowers and fruits from late spring to early fall. P. parviflorus plants usually reach reproductive maturity in their first season of growth from seed. I examined seed germination requirements and phenological traits in twelve populations from across the broad latitudinal range of this species. Seeds from each population were subjected to moist chilling for zero to twelve weeks, and their subsequent germination rates and the timing of phenological events were tracked under common conditions in the greenhouse. Chilling requirements for seed germination were strongly correlated with the latitude of each population. Seeds from the southernmost populations were capable of germinating without chilling and reached their peak germination rates at shorter durations of chilling. Seeds from the northernmost populations failed to germinate with no or brief chilling and required longer chilling periods to achieve high germination rates.

Broader Impacts:

1 - Washington University in St. Louis, Biology, Campus Box 1137, 1 Brookings Drive, St. Louis, MO, 63130, United States

Keywords:
Phemeranthus
Montiaceae
North America
seed germination
geographic variation
latitudinal range
local adaptation.

Presentation Type: Oral Paper:Papers for Sections
Session: 43
Location: 552B/Convention Center
Date: Tuesday, August 3rd, 2010
Time: 1:30 PM
Number: 43001
Abstract ID:580