Abstract Detail

Molecular Ecology and Evolution

Green, Adam [1], Husband, Brian [2].

Genic x Genomic Interactions and the Phenotypic Effects of Whole Genome Duplication.

Polyploidy, the amplification of genome copy number per nucleus, is widespread and recurring throughout the evolutionary history of eukaryotes. Biologists have long sought to explain its prevalence by seeking attributes that are uniformly associated with polyploids and that account for their ecological and evolutionary success. However, the observed association between polyploidy and specific phenotypic traits is often case-specific and confounded by the effects of selection operating after the whole genome duplication event. Here, we assess the magnitude and consistency of direct phenotypic effects of whole genome duplication by synthesizing multiple independent polyploids from each of 45 different diploid genotypes of Arabidopsis thaliana from throughout its European range. We then evaluated them with respect to 10 vegetative and reproductive traits in a common environment. Diploid genotypes differed with respect to nine of 10 traits, and were correlated with longitude and latitude of sampling location. Genome duplication had a significant overall effect on the same nine traits but the direction of effect was not always consistent with the expectation that polyploids are larger. The magnitude of the ploidy effect differed significantly among genotypes and was correlated to different degrees with the phenotype of the diploid progenitor. The phenotypic variance (CV) among replicates within a genotype was larger in tetraploids than diploids, in part due to differences among independently produced polyploids within each genotype. We conclude that polyploidy can have highly variable effects on phenotype that are partially dependent on diploid genotype and phenotype. Strong genic x genomic interactions may accelerate early evolutionary change by generating phenotypic variance and suggest the success of polyploids is not driven by a singular fitness effect but, rather, is contingent upon the ancestral genotype.

1 - Colgate University, Department of Biology, 225 Ho Science Center, 13 Oak Drive, Hamilton, NY, 13346, USA
2 - University Of Guelph, Department Of Integrative Biology, 50 Stone Road E, Guelph, ON, N1G 2W1, Canada

Keywords:
Arabidopsis
plants
Evolution.

Presentation Type: Oral Paper:Papers for Topics
Session: 61
Location: Salon 15/16/The Shaw Conference Centre
Date: Wednesday, July 29th, 2015
Time: 11:30 AM
Number: 61014
Abstract ID:1134
Candidate for Awards:None