Abstract Detail

Biodiversity synthesis: Linking large phylogenies with species traits and ecologies.

Heyduk, Karolina [1], McAssey, Edward [2], Ray, Jeremy [3], Leebens-Mack, Jim [4].

Synthesizing phylogeny and ecophysiology to understand photosynthetic evolution in the Agavoideae.

The evolution of plant ecophysiological traits can be difficult to track across the plant tree of life, largely because these traits can be time consuming to measure and document, and often need to be assessed under a variety of environmental conditions. CAM photosynthesis is an example of a plant trait that requires detailed and extensive physiological measurements. As a result, fine scale understanding of the evolution of CAM from C3 has been hampered by a lack of detailed physiology across closely related taxa in more than a handful of model groups. Adding to the difficulty of understanding CAM photosynthesis, various intermediate forms of CAM exist and are likely more common than previous thought. These intermediate species can use both C3 and CAM photosynthesis, or they can up-regulate CAM only under abiotic stress, such as drought. Yet intermediate species are difficult to find, as they require physiological measurements under both nominal and stressed conditions. Here we describe the evolution of CAM in the Agavoideae, a subfamily of the Asparagaceae where CAM has evolved multiple times. We have used both broad sampling across the whole phylogeny, as well as detailed and robust physiological measurements in a handful of representative species, to fully describe how CAM has evolved independently in the Agavoideae. We synthesize physiology, leaf anatomy, genomics, and molecular evolution to show that independent origins of CAM are associated with different leaf anatomies alternative and gene recruitment into the CAM pathway. Our work highlights both the difficulties in describing the evolutionary trajectory of CAM in a lineage, as well as the benefits of using a multidisciplinary approach to understand the origins of a complex phenotype.

1 - University of Hawai'i, School of Life Sciences, 3190 Maile Way, Honolulu, HI, 96822, USA
2 - University of Hawai'i, School of Life Sciences, 2538 McCarthy Mall, Edmondson 216, Honolulu, HI, 96822, USA
3 - University of Georgia, Plant Biology, 2502 Miller Plant Sciences, Athens, GA, 30605, USA
4 - University Of Georgia, Plant Biology, 2101 Miller Plant Sciences, Athens, GA, 30602, United States

molecular evolution.

Presentation Type: Colloquium Presentations
Session: COL01, Biodiversity synthesis: Linking large phylogenies with species traits and ecologies
Location: Virtual/Virtual
Date: Wednesday, July 29th, 2020
Time: 12:45 PM
Number: COL01010
Abstract ID:223
Candidate for Awards:None

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