Abstract Detail

Systematics Section/ASPT

Chansler, Matt [1], Ferguson, Carolyn J. [2], Fehlberg, Shannon D. [3], Prather, L. Alan [4].

Distinctive phenotypic patterns in polyploid Phlox amabilis (Polemoniaceae).

Polyploidy is known to be an important contributor to taxonomic and ecological diversity in flowering plants. A thorough understanding of the relationship between polyploidy and morphological variation in natural populations is foundational to describing the link between ploidy and evolutionary potential. Which aspects of plant morphology vary with ploidy? Are ploidy levels within a species phenotypically distinguishable? If so, do all morphological characters contribute equally to patterns of variation between ploidy levels? We focus on the association between ploidy and morphological variation within Phlox amabilis. This species of special concern, endemic to Arizona, comprises diploid, tetraploid, and hexaploid individuals. Morphological measurements were collected at 12 sites in 2013; these populations represent most of the species’ extant distribution. Flow cytometry and chromosome counts identified only a single ploidy level at all sites but one; both diploids and tetraploids were detected at Table Top Mountain. We establish a broad assessment of phenotypic variation in P. amabilis and describe its relationship with ploidy via principal components analysis and canonical discriminant analysis. Principal components analysis revealed that morphological differences associated with ploidy accounted for much of the variation between plants. Consequently, plants of each ploidy level grouped together. Canonical discriminant analysis successfully classified 95% of the 253 observations to the correct ploidy level. A final principal components analysis of population means showed a general pattern of grouping by ploidy, but with higher morphological dispersion for diploids than either polyploid group. Considered together, these results support an important role for polyploidy in generating morphological diversity in natural populations of P. amabilis.

1 - Michigan State University, Department of Plant Biology, 612 Wilson Road, East Lansing, MI, 48824, United States
2 - Kansas State University, Division Of Biology, Ackert Hall, Manhattan, KS, 66506-4901, USA
3 - Desert Botanical Garden, 1201 N. Galvin Pkwy., Phoenix, AZ, 85008, USA
4 - Michigan State University, Plant Biology, 612 Wilson Road, Department of Plant Biology, East Lansing, MI, 48824, United States

Keywords:
Phlox
Polyploidy
morphology
Morphometrics
Shape
amabilis
Polemoniaceae
MSU
Arizona
biodiversity.

Presentation Type: Oral Paper:Papers for Sections
Session: 31
Location: Salon 4/The Shaw Conference Centre
Date: Tuesday, July 28th, 2015
Time: 11:15 AM
Number: 31013
Abstract ID:878
Candidate for Awards:George R. Cooley Award