Abstract Detail

Symbioses: Plant, Animal, and Microbe Interactions

Powell, Adrian [1], Halitschke, Rayko [2], Kessler, Andre [2], DOYLE , JEFF J [3].

Nodulation signaling and allopolyploidy in Glycine subgenus Glycine.

Recent genomic studies have highlighted a potential connection between polyploidy and the development and refinement of nodulation symbioses in legumes. Such symbioses involve bacteria that are able to fix atmospheric nitrogen, aiding host plants in meeting the critical challenge of nitrogen acquisition. While the proposal of a connection between polyploidy and nodulation is of great interest, the predictions that follow from it have yet to be tested through direct experimental methods. The present study examines various signaling components involved in the establishment of nodulation symbioses in species of the Glycine subgenus Glycine allopolyploid complex. The specificity of these symbioses is governed by numerous stages of signal, response, and interaction, each of which requires compatibility. Flavonoids are a class of signaling compounds that constitute the first required signal from plant hosts to rhizobia. It has been specifically proposed that polyploidy may have lead to increased diversity of synthesized and exuded flavonoid compounds, which could in turn increase symbiotic opportunities. Our data show that allopolyploids have distinctive exudate profiles, make them different from their diploid progenitors. Our study of plant Nod factor receptors, also necessary for establishment of nodulation symbiosis, indicate that there are relatively low levels of polymorphism and nucleotide diversity in these genes, and that these genes appear to be under purifying selection in species of Glycine subgenus Glycine.

1 - Cornell University, Plant Biology, Ithaca, NY, 14850, USA
2 - Cornell University, Ecology & Evolutionary Biology, Ithaca, NY, 14850, USA
3 - Cornell University, 412 Mann Library Building, ITHACA, NY, 14853-4301, USA

Keywords:
Flavonoids
Nodulation
Glycine subgenus Glycine
allopolyploidy.

Presentation Type: Poster:Posters for Topics
Session: P
Location: Eyrie/Boise Centre
Date: Monday, July 28th, 2014
Time: 5:30 PM
Number: PSB003
Abstract ID:538
Candidate for Awards:None