| Abstract Detail
From Genes to Distributions: physiological ecology as an integrator of polyploid biology John , Grace P [1], Bonnette, Jason [2], McQueen, Alice [3], Zhang, Li [2], Juenger, Thomas [2], Castillo Argaez, Raiza [1]. Anatomical and functional implications of allopolyploidy in Switchgrass (Panicum virgatum) across geographic sites. The coevolution of plant morphological, anatomical, and physiological traits with changes in ploidy have been repeatedly described across many diverse species. However, these strong evolutionary patterns have not yet been integrated into a broad-scale ecological framework. We used Panicum virgatum, a C4 grass for which adaptation to climate and growing season across a broad latitudinal gradient has driven divergence of ecotypes, to test the impact of chromosome duplications on the relationship between plant form and function across environments. We measured traits in two genetic mapping populations planted in common gardens at the northern (Michigan) and southern (Texas) ends of the species’ natural range. Due to spontaneous chromosome duplication events, our population included both allotetraploid and octoploid individuals, allowing for study of 1. Coordination between trait associations with N and K sub-genomes in allotetraploid individuals, 2. Divergence in morphological and anatomical trait networks between tetraploid and octoploid switchgrass, and 3. Dynamic changes in these trait networks across environments. Within the tetraploids, the location of alleles associated with leaf traits was largely asymmetrical between N and K sub-genomes, suggesting no subfunctionalization of anatomical features by sub-genomes. On average, within each site, tetraploid leaves were larger in area, denser, and had larger midribs than octoploids. Notably, there were no significant differences in lamina thickness, leaf mass per area, or saturated water content. Despite well described associations between genome size and cell size across species, we found no consistent pattern of increase in cell size between tetraploid and octoploid leaves. In addition to coordinated shifts in traits across environments associated with a change in growing season length, there were significant differences in the responses to environment between octoploid and tetraploid lines.
1 - University of Florida, Biology, 310 Bartram Hall, 876 Newell Dr, Gainesville, FL, 32611, USA
2 - University of Texas at Austin, Integrative Biology, 2415 Speedway Ave, Austin, TX, 78712, USA
3 - University of Texas at Austin, Integrative Biology, 2415 Speedway Ave, Austin, FL, 78712, USA
Keywords:
Leaf anatomy
polyploidy
functional traits
plant mapping
quantitative trait loci
trait correlations.
Presentation Type: Symposium Presentation
Session: SY3, From Genes to Distributions: physiological ecology as an integrator of polyploid biology
Location: Virtual/Virtual
Date: Wednesday, July 29th, 2020
Time: 1:00 PM
Number: SY3006
Abstract ID:850
Candidate for Awards:None |
