| Abstract Detail
Physiological Section Savage, Jessica Anne [1]. Vascular constraints on flower development: Understanding resource allocation and vascular transport in precocious flowering species. Species distributions are influenced by a variety of biotic and abiotic factors, but what determines a species’ ability to maintain a stable population is its reproductive viability, which in angiosperms can come down to the timing of flower phenology. Across species, there can be selection for earlier flowering in seasonal environments because it helps plants avoids pollen and pollinator competition and provides progeny with a longer growing season. However, early flowering can come with risks, especially in temperate environments, where freezing temperatures can threaten floral development and new growth is limited by carbon storage. Plants that flower precociously (before leaves emerge) may face additional challenges if they have to activate their vascular system early in the season in order to transport the necessary chemical signals and resources into the bud. To better understand how flowering phenology is constrained by the vascular system due to seasonal changes in resource storage and re-mobilization, I compared the physiology and anatomy of ten woody species, five that are precocious bloomers and five close relatives that flower later in the year. Despite my initial hypothesis that precocious flowers are entirely hydrated by the phloem because of the danger associated with ice propagation in the xylem, my data suggest that this is not the case for two of the earliest flowering species. Precocious and non-precocious plants also exhibit significant differences in the timing of reproductive allocation, with earlier flowering plants investing more resources in their overwintering buds. This temporal shift in allocation coincides with changes in leaf phenology including earlier leaf senescence in precocious flowering plants. These data illustrate how aspects of leaf and flower phenology are interconnected and, together with anatomical work, indicate the importance of considering both xylem and phloem activity in the timing of major phenological events. Log in to add this item to your schedule
1 - Arnold Arboretum of Harvard University, 1300 Centre Street, Boston, MA, 02131, USA
Keywords: xylem Phloem phenology Flowering Vascular cambium.
Presentation Type: Oral Paper:Papers for Sections Session: 53 Location: Salon 16/The Shaw Conference Centre Date: Tuesday, July 28th, 2015 Time: 4:00 PM Number: 53008 Abstract ID:617 Candidate for Awards:None |