Abstract Detail

Genetics Section

Lipman, Malorie [1], Chester, Michael [2], Soltis, Pamela [3], Soltis, Douglas [4].

Fluorescence and genomic in situ hybridization (FISH and GISH) reveal chromosome variation in spontaneous natural tri-genomic Tragopogon hybrids.

Chromosome complements of natural tri-genomic Tragopogon hybrids were studied. These plants, which exhibit variation in morphology, fertility and viability, arise spontaneously through hybridization between the recently formed allotetraploidsT. miscellus and T. mirus. The two tetraploid species share T. dubius as a diploid parent; T. dubius combined with T. pratensis in the formation of T. miscellus and with T. porrifolius to form T. mirus. A cytogenetic analysis was conducted using root tips of mature plants by applying four FISH markers and three GISH markers, one for each parental genome. An expected chromosome count of 24 was found in all plants analyzed, however, no plants showed the expected additive karyotype, i.e. one T. porrifolius, one T. pratensis and two T. dubius-derived genomes. Individuals showed different karyotypes, due to aneuploidy and intergenomic translocations. The aneuploidy observed in these hybrids follows a compensatory pattern of putative homeologous chromosome substitutions, similar to what was observed in the allotetraploid Tragopogon miscellus.

Broader Impacts:

1 - University of Florida, Department of Biology, Newell Drive, Gainesville, FL, 32611, USA
2 - University Of Florida, Biology, Gainesville, FL, 32611, USA
3 - University Of Florida, Florida Museum Of Natural History, PO BOX 117800, Gainesville, FL, 32611-7800, USA, 352/273-1964
4 - University Of Florida, Department Of Botany, 220 BARTRAM HALL, Gainesville, FL, 32611, USA

Keywords:
hybridization
FISH
GISH
Polyploidy
aneuploidy
tri-genomic
Tragopogon.

Presentation Type: Poster:Posters for Sections
Session: P
Location: Battelle South/Convention Center
Date: Monday, July 9th, 2012
Time: 5:30 PM
Number: PGN002
Abstract ID:246