| Abstract Detail
Ecology GIBSON, J PHIL [1], Kistenmacher, Michael [2]. Conditional dormancy and germination cueing in heterocarpic Grindelia ciliata (Asteraceae) . Heterocarpy is a reproductive bet-hedging strategy in which plants produce two or more morphologically distinct types of fruit with dissimilar dispersal and germination features. Heterocarpic members of the Asteraceae produce single-seeded fruits, achenes, vary in pericarp thickness, pappus presence or absence, and seed size. Although differences in dispersal and germination are clearly related to structural features of achenes, it is not known whether there are also differences in seed dormancy and germination characteristics that further enhance heterocarpic achene ecology. We investigated the dormancy states of the three achene morphs produced by Grindelia ciliata (Asteraceae) when fresh, and after 30-day and 60-day warm or cold dry after-ripening. Disc achenes are almost completely nondormant and their dormancy state remained unchanged after cold and warm storage. In contrast, most fresh intermediate and ray achenes were conditionally dormant with dormancy induction after exposure to winter temperatures and dormancy loss after exposure to summer temperatures. This study shows that in addition to extreme morphological differences among achenes, G. ciliata achieves additional benefits of bet-hedging through germination cueing. Log in to add this item to your schedule
1 - University of Oklahoma, Department of Microbiology & Plant Biology, Department of Biology, Norman, OK, 73019, USA 2 - University of Oklahoma, Department of Microbiology and Plant Biology, Norman, OK, 73019, USA
Keywords: Grindelia heterocarpy conditional dormancy germination cueing Asteraceae bet-hedging Cox Proportional Hazard Model.
Presentation Type: Poster Session: P, Ecology Location: Exhibit Hall/Omni Hotel Date: Monday, June 26th, 2017 Time: 5:30 PM This poster will be presented at 5:30 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: PEC003 Abstract ID:129 Candidate for Awards:None |