| Abstract Detail
Physiological Section Callahan, Hilary [1], Wiener, N [1], Mattioli, M [1], Celcis, N [1], Mo, J [1], Patterson, AE [1]. Fitness effects of allelic variation at the FRI and FLC loci of Arabidopsis thaliana: field and lab studies of recombinant inbred populations. Flowering time in the absence of vernalization is used to classify genotypes of Arabidopsis thaliana as late or early flowering. This distinction is commonly associated with allelic variation at FRIGIDA (FRI) and FLOWERING LOCUS C (FLC), functionally related but physically unlinked loci. We conducted lab and field studies to corroborate associations among flowering habit, fitness, and allelism at FRI and FLC. Our studies used three populations of recombinant inbred lines. The Ler × Col population harbors one normal and one functionally attenuated FLC allele with two non-functional fri alleles. In the Ler × Sha population, both FLC alleles are attenuated, and segregate with a functional and a non-functional FRI allele. The Bay-0 × Sha population has segregating variation for both FLC and FRI. In all studies we scored fitness, and selection gradient analyses addressed the adaptive significance of flowering habit and associated flowering time genes. We also did plasticity cost analyses, examining whether variation in fitness associates with the ability to plastically adjust flowering in response to an environmental variable (duration of vernalization). Large numbers of genotypes in each population aided detection of plasticity costs. We found directional selection for early flowering not only in lab treatments that partially vernalize plants (i.e., brief winter), but also in treatments mimicking full vernalization (i.e., long winter). We have also found selection for early flowering in field studies. The ecological relevance of plasticity costs remains questionable; they were small and specific to particular treatments and populations. Log in to add this item to your schedule
1 - Barnard College, Columbia University, Department of Biological Sciences, 3009 Broadway, New York, New York, 10027, USA
Keywords: ecological genetics FRIGIDA FLOWERING LOCUS C flowering time phenotypic plasticity plasticity cost.
Presentation Type: Poster:Posters for Sections Session: P Location: Exhibit Hall (Northeast, Southwest & Southeast)/Hilton Date: Sunday, July 8th, 2007 Time: 8:00 AM Number: P56007 Abstract ID:2117 |