Lloyd, Melanie .
The characterization of eve, a novel Medicago truncatula mutant affecting both nodulation and root and shoot architecture.
The symbiotic relationship between the model legume, Medicago truncatula, and Rhizobium bacteria results in the formation of nodules, nitrogen-fixing root organs formed through the interaction of both partners. It is hypothesized that this relatively new process evolved from pre-existing genetic programs. Mutants defective in both nodule and plant development could identify genes and pathways recruited from a plant developmental process to nodule formation. The eve mutant, isolated in our lab, has deficiencies in both nodulation and plant development. The plant host is responsible for regulating nodule number in a process called autoregulation of nodulation. When this process is broken, excess nodules are observed, as in the case of eve. Furthermore, the eve supernodulating phenotype is sensitive to both the Red:Far Red ratio as well as the presence of wild-type neighbors when planted on Petri plates. Changes in root architecture were also observed in eve mutants including shorter root hairs, a straighter primary root, and an increased angle between the primary root and emerging lateral roots. In addition, the eve mutation results in changes to shoot architecture, increased anthocyanin production in leaves, and altered responses to far red light enhancement. We are currently continuing our genetic and phenotypic characterization of the eve mutant, and hope that this analysis will help us in understanding the evolution of nodulation.
Log in to add this item to your schedule
1 - University of Vermont, Plant Biology, 109 Carrigan Dr, Burlington, VT, 05405, USA
Presentation Type: Plant Biology Abstract
Location: Exhibit Hall (Northeast, Southwest & Southeast)/Hilton
Date: Sunday, July 8th, 2007
Time: 8:00 AM